Nutrition and health

Objectives:
Epidemiological studies have shown the preventive effects of olive oil consumption against cardiovascular events and all-cause deaths, but the results remain inconsistent. Therefore, this meta-analysis (review article) has been conducted.

Does higher olive oil consumption reduce the risk of cardiovascular disease and all-cause mortality?

Study design:
This review article included 13 prospective cohort studies.
These studies were published between 2003 and 2022, with follow-up intervals ranging from 4 to 28 years.
Most of studies collected the dietary data on olive oil intake based on food-frequency questionnaires and the outcome events were identified using International Classification of Diseases codes or other medical records.
All of the studies were assigned a NOS score of ≥7, indicating the evidence of high methodological quality.
There was no publication bias.

Results and conclusions:
The investigators found meta-analysis of 8 cohort studies (261,016 participants and 14,033 cardiovascular disease cases) showed versus lowest consumption of olive oil, high consumption of olive oil significantly reduced risk of cardiovascular disease with 15% [pooled RR = 0.85, 95% CI = 0.77 to 0.93, p 0.001, I2 = 41%, p = 0.107].
Subgroup analyses showed no significant differences between strata of study region, sample size, follow-up duration, sex and olive oil type.
The combined risk estimate of cardiovascular disease was not altered in the sensitivity analysis by omitting each study one at a time.

The investigators found meta-analysis of 11 cohort studies (713,000 participants and 173,817 deaths) showed versus lowest consumption of olive oil, high consumption of olive oil significantly reduced risk of all-cause mortality with 17% [pooled RR = 0.83, 95% CI = 0.77 to 0.90, p 0.001, I2 = 93%, p 0.001].
Excluding each report in sequence had no influence on the pooled result.
The combined RRs were similar between subsets stratified by the aforementioned features.

The investigators found in dose-response meta-analysis, a significantly reduced risk of 4% for cardiovascular disease per 5-g/day increase in olive oil intake [RR = 0.96, 95% CI = 0.93 to 0.99, p = 0.005].

The investigators found in dose-response meta-analysis, a significantly reduced risk of 4% for all-cause mortality per 5-g/day increase in olive oil intake [RR = 0.96, 95% CI = 0.95 to 0.96, p 0.001].

The investigators found non-linear associations of olive oil intake with cardiovascular disease and all-cause mortality [both p for non-linearity 0.001], with little additional or no risk reduction observed beyond the consumption of approximately 20 g/day.

The investigators concluded that olive oil consumption reduces the risk of cardiovascular disease and all-cause mortality. Such benefits seem to be obtained with an intake of olive oil up to 20 g/day. These results support the current dietary recommendations to increase the intake of olive oil instead of other fats for improving human health and longevity. Future prospective studies are required to further depict the dose-dependent cardiovascular and survival effects in relation to olive oil consumption.

Original title:
Olive oil consumption and risk of cardiovascular disease and all-cause mortality: A meta-analysis of prospective cohort studies by Xia M, Zhong Y, [...], Qian C.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9623257/

Additional information of El Mondo:
Find more information/studies on olive oil consumption and cardiovascular disease right here.

Objectives:
Although numerous studies have reported the protective effect of nut consumption on cardiovascular risk, evidence for the role of peanuts in maintaining cardiometabolic health is inconclusive. Therefore, this meta-analysis (review article) has been conducted.

Does a high consumption of peanuts improve causally cardiovascular risk factors, such as cholesterol levels and LDL/HDL ratio?

Study design:
This review article included 10 RCTs (8 parallel RCTs and 3 crossover RCTs) with a total of 643 participants (316 males and 327 females) aged between 18 and 84 years from Asia, North America, Europa, South America and Australia.

The administered doses of peanuts ranged between 25 and 200 g/d, with follow-up periods of 2-24 weeks.

The strength of evidence varied from very low to moderate, depending on the outcomes.

Results and conclusions:
The investigators found meta-analysis of clinical trials revealed that peanut consumption was significantly associated with a decrease in triglycerides levels compared to the control interventions [MD = -0.13, 95% CI = -0.20 to -0.07, p 0.0001].
This significant reduction was most acute in healthy subjects [MD = -0.13, 95% CI = -0.25 to -0.00, p = 0.04] and in those who consumed peanuts or peanut butter [MD = -0.14, 95% CI = -0.20 to -0.07, p 0.0001].

The investigators found meta-analysis of clinical trials revealed that peanut consumption signicantly lowered total cholesterol levels among healthy consumers [MD = -0.40, 95% CI = -0.71 to -0.09, p = 0.01].

The investigators found meta-analysis of clinical trials revealed that peanut consumption signicantly lowered total cholesterol levels among healthy consumers [MD = -0.40, 95% CI = -0.71 to -0.09, p = 0.01].

The investigators found meta-analysis of clinical trials revealed that peanut consumption resulted in a signicantly lower LDL-cholesterol/HDL-cholesterol ratio among healthy consumers [MD = -0.19, 95% CI = -0.36 to -0.01, p = 0.03].

The investigators found, however, individuals at high cardiometabolic risk experienced a significant increase in body weight after the peanut interventions [MD = 0.97, 95% CI = 0.54 to 1.41, p 0.0001], although not in body fat or body mass index.

The investigators found, according to the dose-response analyses, body weight increased slightly with higher doses of peanuts.

The investigators concluded that consumption of 25-200 g/d peanuts during 2-24 weeks may causally reduce triglycerides and total cholesterol levels. May reduce because the strength of evidence varied from very low to moderate. To gain more knowledge about the effects of peanut products on cardiometabolic risk factors, more carefully designed studies in larger populations are needed.

Original title:
Effect of Peanut Consumption on Cardiovascular Risk Factors: A Randomized Clinical Trial and Meta-Analysis by Parilli-Moser I, Hurtado-Barroso S, […], Lamuela-Raventós RM.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9011914/

Additional information of El Mondo:
Find more information/studies on nuts consumption, cholesterol and cardiovascular disease right here.

Objectives:
Previous studies on the effect of Brassica vegetables on blood glucose and lipid profile have reported inconclusive findings. Therefore, this meta-analysis (review article) has been conducted.

Does higher Brassica vegetables consumption improve causally cardiovascular risk factors (levels of triglycerides, cholesterol, fasting blood sugar and glycated haemoglobin)?

Study design:
This review article included 9 RCTs with a total of 548 participants.

Results and conclusions:
The investigators found pooled analysis indicated a significant reduction in total cholesterol (TC) [SMD = -0.28, 95% CI = -0.48 to -0.08, p = 0.005] following Brassica vegetables consumption.

The investigators found, overall, Brassica vegetables had no significant impact on serum levels of triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, fasting blood sugar and glycated hemoglobin.

The investigators concluded that consumption of Brassica vegetables causally reduces total cholesterol concentration. However, further high-quality studies are needed to firmly establish the clinical efficacy of these plants.

Original title:
The effect of Brassica vegetables on blood glucose levels and lipid profiles in adults. A systematic review and meta-analysis by Darand M, Alizadeh S and Mansourian M.

Link:
https://pubmed.ncbi.nlm.nih.gov/35412701/

Additional information of El Mondo:
Find more information/studies on Brassica vegetables consumption, cholesterol and cardiovascular disease right here.

Brassica vegetables are broccoli, Brussels sprouts, cabbage, cauliflower, collard greens, kale and turnips.

Objectives:
Although several meta-analyses have revealed the beneficial effects of dietary fiber intake on human health, some have reported inconsistent findings. Therefore, this umbrella meta-analysis (review article) has been conducted.

Does higher dietary fiber intake improve causally cardiovascular risk factors?

Study design:
This umbrella review article included 52 meta-analyses of RCTs with a total of 47,197 subjects.

Of the 52 meta-analyses, 35 used high-quality studies, 9 used studies with moderate quality, 7 did not report the quality of the included studies and 1 used low-quality studies.

The dosages and durations of dietary fiber intervention ranged from 3 g/day to 30 g/day (except for one study, which used guar gum at 15 mg/day and another study that used brown rice at 225 g/d) and 4 to 13 weeks, respectively.

Results and conclusions:
The investigators found, overall, higher dietary fiber intake significantly reduced:
-fasting plasma glucose [ES = -0.55, 95% CI = -0.73 to -0.38, p 0.001];
-fasting plasma insulin [ES = -1.22, 95% CI = -1.63 to -0.82, p 0.001];
-homeostasis model assessment of insulin resistance (HOMA-IR) [ES = -0.43, 95% CI = -0.60 to -0.27, p 0.001];

-glycosylated hemoglobin (HbA1c) [ES = -0.38, 95% CI = -0.50 to -0.26, p 0.001];
-serum level of total cholesterol [ES = -0.28, 95% CI = -0.39 to -0.16, p 0.001];
-low-density lipoprotein cholesterol (bad cholesterol) [ES = -0.25, 95% CI = -0.34 to -0.16, p 0.001];
-tumor necrosis factor-alpha serum levels [ES = -0.78, 95% CI = -1.39 to -0.16, p = 0.013];
-systolic blood pressure [ES = -1.72, 95% CI= -2.13 to -1.30, p 0.001];
-diastolic blood pressure [ES = -0.67, 95% CI = -0.96 to -0.37, p 0.001].
Significant means that there is an association with a 95% confidence.

The investigators found sensitivity analysis showed that the overall ESs did not change by excluding any individual meta-analysis.

The investigators found subgroup analysis revealed that the study population and type of dietary fiber could be partial sources of heterogeneity.

The investigators concluded that the present umbrella meta-analysis strongly support the beneficial effects of dietary fiber intake for the improvement cardiovascular risk factors, in particular cholesterol, fasting blood sugar, HbA1c, tumor necrosis factor-alpha and fasting insulin level, blood pressure and HOMA-IR value. However, it should be noted that the health-promoting effects of dietary fiber intake may differ between populations with different metabolic diseases.

Original title:
Associations between dietary fiber intake and cardiovascular risk factors: An umbrella review of meta-analyses of randomized controlled trials by Fu L, Zhang G, […], Tan M.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9511151/

Additional information of El Mondo:
Find more information/studies on dietary fiber consumption, diabetes, high blood pressure and cardiovascular disease right here.

A high dietary fiber intake corresponds to a diet with at least 1.5 grams fiber per 100 kcal. Use the 7-points nutrition profile app to see if your daily diet contains 1.5 grams fiber per 100 kcal.
These products in the supermarket contain 1.5 grams fiber per 100 kcal.

An umbrella review article is a scientific article which only includes meta-analyses (also called review articles). The results found in an umbrella review article are more reliable than found in an individual review article.

One swallow does not make a summer. A famous Dutch saying that could not be any more obvious. Just because one single scientific study about a certain topic makes certain claims, it does not necessarily mean it is true. On the other hand, a review article (a collection of scientific studies on a certain topic) of randomized, placebo-controlled double blind clinical trials (RCTs) will answer the following question:
"Do taking dietary supplements make sense?" Yes for a positive conclusion and no for a negative conclusion.

One swallow does not make a summer. A famous Dutch saying that could not be any more obvious. Just because one single scientific study about a certain topic makes certain claims, it does not necessarily mean it is true. On the other hand, a review article (a collection of scientific studies on a certain topic) of (prospective) cohort studies or case-control studies will answer the following question:
"Should I change my diet?".

Objectives:
Several epidemiological studies have suggested that flavonoid intake is associated with a decreased risk of cardiometabolic disease. However, the results remained inconsistent and there is no dose-response meta-analysis for specific outcomes. Therefore, this review article has been conducted.

Is there a dose-response relationship between dietary flavonoid intake and reduced risk of cardiometabolic disease?

Study design:
This review article included 47 prospective cohort studies with a total of 1,346,676 participants and 127,507 persons with cardiometabolic disease.

Results and conclusions:
The investigators found for every 500 mg/d increase in dietary flavonoid intake a reduced risk of 7% [summary RR = 0.93, 95% CI = 0.88 to 0.98] for cardiovascular disease.
Significant means that there is an association with a 95% confidence.

The investigators found for every 500 mg/d increase in dietary flavonoid intake a reduced risk of 11% [summary RR = 0.89, 95% CI = 0.84 to 0.94] for diabetes.
Significant because summary RR of 1 was not found in the 95% CI of 0.84 to 0.94. Summary RR of 1 means no risk/association.

The investigators found for every 500 mg/d increase in dietary flavonoid intake a reduced risk of 3% [summary RR = 0.97, 95% CI = 0.94 to 0.99] for hypertension.
Significantly means it can be said with a 95% confidence that every 500 mg/d increase in dietary flavonoid intake really reduced risk of hypertension with 3%.

The investigators found a linearity dose-response association between total dietary flavonoid intake and cardiovascular disease [p nonlinearity = 0.541] and diabetes [p nonlinearity = 0.077].

The investigators concluded that a higher level of dietary flavonoid intake, at least 500 mg/d  is beneficial for the prevention of cardiometabolic diseases, particularly cardiovascular disease, diabetes and hypertension.

Original title:
Total dietary flavonoid intake and risk of cardiometabolic diseases: A dose-response meta-analysis of prospective cohort studies by Li T, Zhao Y, […], Liu J.

Link:
https://pubmed.ncbi.nlm.nih.gov/36148848/

Additional information of El Mondo:
Find more information/studies on flavonoid, diabetes, cardiovascular disease and lowering blood pressure right here.

Cardiometabolic diseases are a group of common but often preventable conditions including heart attack, stroke, diabetes, insulin resistance and non-alcoholic fatty liver disease.

Objectives:
Findings of observational studies that evaluated the association of serum vitamin D status and high blood pressure were contradictory. Therefore, this review article has been conducted.

Does a high serum vitamin D concentration reduce risk of hypertension in the adult population?

Study design:
This review article included 10 prospective cohort, 1 nested case-control study and 59 cross-sectional studies.
Overall 66,757 and 260,944 participants were included in cohort and cross-sectional studies, respectively.
Among cohort studies, the NOS scores were between 6 and 9.
Among cross-sectional studies, the NOS scores ranged between 4 and 10.
There was no publication bias.

Results and conclusions:
The investigators found in the pooled analysis of cohort studies (66,757 participants) a 16% significant decrease in risk of hypertension in participants who had a high level of serum vitamin D compared with those with low level [pooled RR = 0.84, 95% CI = 0.73 to 0.96, I2 = 64%, p = 0.001].
Sensitivity analysis showed that excluding each stuy had no significant effect on pooled RR.

The investigators found combining effect sizes of 10 cohort studies involving a total of 63,602 individuals and 25,019 cases of hypertension showed that each 25 nmol/L increase in serum vitamin D level resulted in a 5% reduction in risk of hypertension [RR = 0.95, 95% CI = 0.90 to 1.00].
Also, a significant non-linear association between serum vitamin D levels and hypertension was observed [p non-inearity 0.001].
A reduction trend in risk of hypertension was observed for serum vitamin D levels between 45 and 70 nmol/L, although for higher vitamin D levels the risk did not decrease anymore and eventually started increasing.

The investigators found meta-analysis of cross-sectional studies showed that highest level of vitamin D in comparison to the lowest level was associated with a 16% significant decrease in risk of hypertension [OR overall = 0.86, 95% CI = 0.79 to 0.90, I2 = 67.5%, p 0.001].
Sensitivity analysis determined that the exclusion of each study did not significantly affect the overall estimate.

The investigators found combining effect sizes of 30 cross-sectional studies involving a total of 139,685 individuals and 40,178 cases of hypertension showed that each 25 nmol/L increase in serum vitamin D level resulted in a 6% reduction in risk of hypertension [OR = 0.94, 95% CI = 0.90 to 0.99].  

Also, a significant non-linear association between serum vitamin D levels and hypertension was seen [p non-linearity 0.001].
A reduction trend in risk of hypertension was observed for serum vitamin D levels between 40 and 75 nmol/L, although higher vitamin D levels did not reduce odds of hypertension.

The investigators concluded that serum vitamin D concentrations between 40 and 75 nmol/L reduce risk of hypertension in the adult population, in both prospective cohort and cross-sectional studies.

Original title:
Serum Vitamin D Levels in Relation to Hypertension and Pre-hypertension in Adults: A Systematic Review and Dose-Response Meta-Analysis of Epidemiologic Studies by Mokhtari E, Hajhashemy Z and Saneei P.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8961407/

Additional information of El Mondo:
Find more information/studies on vitamin D and lowering blood pressure right here.

Objectives:
Dietary fats are one of the well-known stimulators of carotenoid absorption, but the effects of the quantity and the type of dietary fats on carotenoid absorption have not yet been studied systematically. Therefore, this review article has been conducted.

Do dietary fats improve the absorption of carotenoids?

Study design:
This review article included a total of 27 in vitro studies and 12 RCTs.

Results and conclusions:
The investigators found meta-regression of in vitro studies showed that the bioaccessibility of carotenoids, except for lycopene, was positively associated with the concentration of dietary fats.

The investigators found meta-analysis of RCTs showed that the bioavailability of carotenoids was enhanced when a higher quantity of dietary fats was co-consumed.

The investigators found, moreover, fats rich in unsaturated fatty acids resulted in greater improvement in carotenoid bioavailability [SMD = 0.90, 95% CI = 0.69 to 1.11] as compared with fats rich in saturated fatty acids [SMD = 0.27, 95% CI = 0.08 to 0.47].

The investigators concluded that co-consuming dietary fats, particularly those rich in unsaturated fatty acids, with carotenoid-rich foods can improve the absorption of carotenoids.

Original title:
Effects of dietary fats on the bioaccessibility and bioavailability of carotenoids: a systematic review and meta-analysis of in vitro studies and randomized controlled trials by Yao Y, Tan P and Kim JE.

Link:
https://pubmed.ncbi.nlm.nih.gov/34897461/

Additional information of El Mondo:
Find more information/studies on carotenoids consumption right here.

Objectives:
Epidemiological studies indicate that higher intakes of flavonoids are associated with reduced stroke risk. However, which subtypes play significant roles to protect against stroke remain unclear. Therefore, this review article has been conducted.

Does dietary intake of different flavonoid subclasses (flavanones, flavan-3-ols) reduce risk of stroke?

Study design:
This review article included 10 independent prospective cohort studies with 387,076 participants and 9,564 events (persons with stroke).

Results and conclusions:
The investigators found higher intakes of flavanones significantly reduced risk of stroke with 15% [RR = 0.85, 95% CI = 0.78 to 0.93].

The investigators found dose-response analysis showed that 50 mg/day increment of flavanones dietary intake was significantly associated with 11% reduction in stroke risk [RR = 0.89, 95% CI = 0.84 to 0.94].

The investigators found dose-response analysis showed that 200 mg/day increment of flavan-3-ols dietary intake was significantly associated with 14% reduction in stroke risk [RR = 0.86, 95% CI = 0.75 to 0.98].

The investigators found no association with respect to other flavonoid subclasses.

The investigators concluded that both 50 mg/day flavanones and 200 mg/day flavan-3-ols dietary intake reduce stroke risk. The findings of these associations of the present study need to be confirmed in other regions and ethnic origins.

Original title:
A meta-analysis of prospective cohort studies of flavonoid subclasses and stroke risk by Li XQ, Wang C, […], Guo XF.

Link:
https://pubmed.ncbi.nlm.nih.gov/35023220/

Additional information of El Mondo:
Find more information/studies on flavonoid consumption and stroke prevention right here.

Objectives:
Oat supplementation interventions (OSIs) may have a beneficial effect on cardiovascular disease (CVD) risk. However, dietary background can modulate such effect. Therefore, this review article has been conducted.

Does dietary oat supplementation lower levels of blood lipids (cholesterol, triglycerides) and improve anthropometric parameters (glucose level, body mass index, weight, blood pressure, waist circumference) among participants with predominantly mild metabolic disturbances?

Study design:
This review article included 74 RCTs with a total of 4,937 predominantly hypercholesterolemic, obese subjects, with mild metabolic disturbances. Of these, 59 RCTs contributed to the meta-analyses.

The majority of included RCTs (81.1%) had some concerns for risk of bias.

Results and conclusions:
The investigators found oat supplementation (as oat, oat beta-glucan-rich extracts or avenanthramides), compared to control arms without oats, significantly improved levels of:
-total cholesterol (TC) [WMD = -0.42 mmol/L, 95% CI = -0.61 to -0.22];
-LDL cholesterol [WMD = -0.29 mmol/L, 95% CI = -0.37 to -0.20];
-glucose [WMD = -0.25 nmol/L, 95% CI = -0.36 to -0.14];
-body mass index [WMD = -0.13 kg/m², 95% CI = -0.26 to -0.01];
-weight [WMD = -0.94 kg, 95% CI = -1.84 to -0.05] and;
-waist circumference [WMD = -1.06 cm, 95% CI = -1.85 to -0.27].

The investigators found RCTs on inflammation and/or oxidative stress markers were scarce and with inconsistent findings.

The investigators found RCTs comparing an oat supplementation intervention to heterogeneous interventions (e.g., wheat, eggs, rice, etc.), showed lowered levels of glycated haemoglobin, diastolic blood pressure, HDL cholesterol and apolipoprotein B.

The investigators concluded dietary oat supplementation (as oat, oat beta-glucan-rich extracts or avenanthramides) may lower levels of blood lipids and improve anthropometric parameters among obese participants with predominantly mild metabolic disturbances, regardless of dietary background or control. May lower because the majority of included RCTs had some concerns for risk of bias. Therefore, further high-quality trials are warranted to establish the role of oat supplementation intervention on blood pressure, glucose homeostasis and inflammation markers.

Original title:
Effect of oat supplementation interventions on cardiovascular disease risk markers: a systematic review and meta-analysis of randomized controlled trials by Llanaj E, Dejanovic GM, […], Muka T.

Link:
https://pubmed.ncbi.nlm.nih.gov/34977959/

Additional information of El Mondo:
Find more information/studies on oat consumption, overweight and cardiovascular diseases right here.

These products are suitable for persons with cardiovascular diseases.

Objectives:
What is the relationship between serum, dietary and urinary potassium and the risk of type 2 diabetes mellitus (T2DM)?  

Study design:
This review article included 8 prospective cohort studies involved 5,053 type 2 diabetes mellitus cases among 119,993 individuals.
The follow-up durations were from 5 to 18.1 years with a baseline age range from 18 to 95 years.
Serum potassium was measured using the ion-selective electrode method. Dietary potassium was estimated from food frequency questionnaire (FFQ). Urinary potassium samples were analyzed by potentiometric methods.
Most of the included studies provided risk estimates adjusted for age, sex, race, BMI and family history of diabetes.

Results and conclusions:
The investigators found in 5 studies involving 28,944 individuals and 3,849 type 2 diabetes mellitus cases, a non-significantly reduced risk of 21% [summary RR = 0.79, 95% CI = 0.60-1.04, I2 = 76.7%] for type 2 diabetes mellitus, when comparing the highest versus lowest serum potassium levels.
However, the sensitivity analysis did show a significant inverse association between serum potassium and type 2 diabetes mellitus risk [RR = 0.63, 95% CI = 0.52-0.73, I2 = 0%].

The investigators found in random dose-response meta-regression analysis a significantly reduced risk of 17% for type 2 diabetes mellitus [RR = 0.83, 95% CI = 0.73-0.95] per 1 mmol/L increase in serum potassium.

The investigators found in 6 studies involving 112,125 individuals and 4,573 type 2 diabetes mellitus cases, a non-significantly reduced risk of 7% [RR = 0.93, 95% CI = 0.81-1.06, I2 = 0.0%, p = 0.52] for type 2 diabetes mellitus, when comparing the highest versus lowest dietary potassium intake.
The sensitivity analysis did not significantly alter the association between dietary potassium and type 2 diabetes mellitus risk.

The investigators found there was no significant dose-response relationship between dietary potassium and type 2 diabetes mellitus risk [RR for every 1000mg increase dietary potassium per day = 1.00, 95% CI = 0.96-1.05].

The investigators found in 3 studies involving 4,376 individuals and 455 type 2 diabetes mellitus cases, a non-significantly reduced risk of 17% [RR = 0.83, 95% CI = 0.39-1.75, I2 = 73.9%, p = 0.02] for type 2 diabetes mellitus, when comparing the highest versus lowest urinary potassium levels.

The investigators found there was no significant dose-response relationship between urinary potassium levels and type 2 diabetes mellitus risk [RR for 10 mmol increase in urinary potassium per 24 hours = 1.00, 95% CI = 0.95-1.05].

The investigators concluded that serum potassium levels are linearly associated with the risk of type 2 diabetes mellitus, with each 1 mmol/L increase in serum potassium lowering the risk by 17%. However, neither dietary potassium nor urinary potassium shows any association with the risk of type 2 diabetes mellitus.

Original title:
Potassium measurements and risk of type 2 diabetes: a dose-response meta-analysis of prospective cohort studies by Peng Y, Zhong GC, […], Yang G.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5725047/

Additional information of El Mondo:
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Objectives:
Over the last 7 years there has been intense debate about the advice to reduce saturated fat and increase polyunsaturated fat to reduce cardiovascular (CVD) risk. Therefore, this review article (meta-analysis) has been conducted.

Does replacement of saturated fat with carbohydrate, polyunsaturated fatty acid (PUFA) or monounsaturated fatty acid (MUFA) reduce cardiovascular risk?

Study design:
This review article included cohort studies and intervention studies.

Results and conclusions:
The investigators found replacement of saturated fat with any carbohydrate, polyunsaturated fatty acid (PUFA) and monounsaturated fatty acid (MUFA) is associated with lower mortality with PUFA being more effective than MUFA [19% reduction versus 11%].

The investigators found per 5% of energy (5 En%) replacement of saturated fat with polyunsaturated fatty acid and fish oil significantly lowered risk of cardiovascular mortality with 28%.  

The investigators found replacing saturated fat with PUFA or MUFA was equally effective at reducing coronary heart disease (CHD) events

The investigators found replacement of saturated fat with whole grains significantly lowered coronary heart disease events while replacement with sugar and starch significantly increased coronary heart disease events.

The investigators found replacement of saturated fat with carbohydrate had no effect on coronary heart disease events or death.

The investigators found only PUFA replacement of saturated fat significantly lowered coronary heart disease events and cardiovascular and total mortality.

The investigators concluded reducing saturated fat and replacing it with carbohydrate will not lower coronary heart disease events or cardiovascular mortality although it will reduce total mortality. Replacing saturated fat with PUFA, MUFA or high-quality carbohydrate will lower coronary heart disease events.

Original title:
A systematic review of the effect of dietary saturated and polyunsaturated fat on heart disease by Clifton PM and Keogh JB.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29174025

Additional information of El Mondo:
Find more information/studies on fat, carbohydrates and cardiovascular diseases right here.

Objectives:
What are the cardiovascular benefits of indiscriminate supplementation of omega-3 supplementation?

Study design:
This review article included 8 RCTs.

Results and conclusions:
The investigators found omega-3 supplementation significantly resulted in a 8% decrease of the risk of cardiac death, unless the patients are treated by statins.

The investigators found omega-3 supplementation prolonged quality adjusted life years by about a month. Old people gained less, whereas diabetes mellitus type 2 patients and people with history of cardiovascular events gained more.

The investigators concluded omega-3 supplementation decreases risk of cardiac death, unless the patients are treated by statins.

Original title:
The cardiovascular benefits of indiscriminate supplementation of omega-3 fatty acids; meta-analysis and decision-making approach by Leshno M, Goldbourt U, [...], Lichtenberg D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29171335

Additional information of El Mondo:
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Objectives:
Beetroot is considered a complementary treatment for hypertension because of its high content of inorganic NO3.

The aim of this meta-analysis (review article) is to clarify several aspects of beetroot juice supplementation on systolic blood pressure (SBP) and diastolic blood pressure (DBP).

Study design:
This review article included 22 RCTs with a total of 47 intervention (n = 650) and 43 control (n = 598) groups.

Results and conclusions:
The investigators found overall, systolic blood pressure [-3.55 mmHg, 95% CI = -4.55 to -2.54 mmHg] and diastolic blood pressure [-1.32 mmHg, 95% CI = -1.97 to -0.68 mmHg] were significantly lower in the beetroot juice-supplemented groups than in the control groups.

The investigators found the mean difference of systolic blood pressure was larger between beetroot juice-supplemented and control groups in the longer than in the shorter (≥14 compared with 14 days) study durations [-5.11 compared with -2.67 mmHg].

The investigators found the mean difference of systolic blood pressure was larger between beetroot juice-supplemented and control groups in the highest compared with the lowest (500 compared with 70 and 140 mL/d] doses of beetroot juice [-4.78 compared with -2.37 mmHg].

The investigators found a positive correlation between beetroot juice doses and the mean differences of blood pressures.

The investigators found a smaller effect size of blood pressures after supplementation with higher NO3 (milligrams per 100 mL beetroot juice).

The investigators found a weak effect size in a meta-analysis of trials that used NO3-depleted beetroot juice as a placebo compared with other interventions [-3.09 compared with -4.51 mmHg for systolic blood pressure and -0.81 compared with -2.01 mmHg for diastolic blood pressure].

The investigators concluded beetroot juice supplementation, particularly 500 mL/d beetroot juice during at least 14 days, reduces blood pressure.

Original title:
The Nitrate-Independent Blood Pressure-Lowering Effect of Beetroot Juice: A Systematic Review and Meta-Analysis by Bahadoran Z, Mirmiran P, […], Ghasemi A.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29141968

Additional information of El Mondo:
Find more information/studies on fruit, hypertension prevention and cardiovascular diseases right here.

Objectives:
What is the relationship of the intake of whole grains, refined grains, vegetables, fruits, nuts, legumes, eggs, dairy, fish, red meat, processed meat and sugar-sweetened beverages (SSBs) and the risk of hypertension?

Study design:
This review article included 28 prospective cohort studies.

Results and conclusions:
The investigators found in dose-response meta-analysis of 4 studies with 28,069 incident hypertension cases, a significantly reduced risk of 8% [RR = 0.92, 95% CI = 0.87-0.98, I2 = 88%, p 0.0001] for hypertension for 30 g/day whole grains. Significant means that there is an association with a 95% confidence.
The reduced risk was highest (15%) at 90 g/day whole grains.

The investigators found in dose-response meta-analysis of 6 studies, a significantly reduced risk of 3% [RR = 0.97, 95% CI = 0.96-0.99, I2 = 64%, p = 0.02] for hypertension for 100 g/day fruits.
The strongest risk reduction was 7% at 300 g/day fruits.

The investigators found in dose-response meta-analysis of 9 studies with 31,509 incident hypertension cases, a significantly reduced risk of 5% [RR = 0.95, 95% CI = 0.94-0.97, I2 = 0%, p = 0.50] for hypertension for 200 g/day dairy products.
The strongest risk reduction was 15% at 800 g/day dairy products.

The investigators found in dose-response meta-analysis of 7 studies with 97,745 incident hypertension cases, a significantly increased risk of 14% [RR = 1.14, 95% CI = 1.02-1.28, I2 = 88%, p 0.001] for hypertension for 100 g/day red meat.
The increased risk was highest (40%) at 200 g/day red meat.

The investigators found in dose-response meta-analysis of 4 studies, a significantly increased risk of 12% [RR = 1.12, 95% CI = 1.00-1.26, I2 = 82%, p 0.001] for hypertension for 50 g/day processed meat.

The investigators found in dose-response meta-analysis of 4 studies, a significantly increased risk of 7% [RR = 1.07, 95% CI = 1.04-1.10, I2 = 64%, p = 0.04] for hypertension for 250 mL/day sugar-sweetened beverages.
The increased risk was highest (13%) at 450 mL/day sugar-sweetened beverages.

The investigators found compared with nonconsumption, an intake of 2 servings red meat/d [170g, RR = 1.35], 1 serving processed meat/d [35g, RR = 1.07], 1 serving fish/d [100g, RR = 1.08] and 2 servings sugar-sweetened beverages/d [500mL, RR = 1.14 was associated with a 78% increased risk of hypertension. On the other hand, a risk reduction by 44% would be achieved by not consuming these foods (red meat, processed meat, fish and sugar-sweetened beverages).

The investigators concluded a daily dietary intake of 30g whole grains, 100g fruits, 200g dairy products reduce risk of hypertension, whereas a daily dietary intake of 100g red meat, 50g processed meat, and 250mL sugar-sweetened beverages increase risk of hypertension. These findings need to be seen under the light of very-low to low credibility of meta-evidence. However, the findings support the current dietary recommendations in the primary prevention of hypertension.

Original title:
Food Groups and Risk of Hypertension: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies by Schwingshackl L, Schwedhelm C, […], Boeing H.

Link:
http://advances.nutrition.org/content/8/6/793.long

Additional information of El Mondo:
Find more information/studies on different food groups, hypertension prevention and cardiovascular diseases right here.

Objectives:
Previous meta‐analyses on meat intake and risk of stroke did not report the effect of white meat (poultry meat, excluding fish) and did not examine stroke incidence and mortality separately. Therefore, this review article (meta-analysis) has been conducted.

What is the relationship of total (red and processed meat), red (unprocessed or fresh red meat) and processed (processed red meat) meat consumption along with white meat on risk of stroke incidence and mortality disease risk?

Study design:
This review article included 15 prospective cohort studies (254,742 participants with 9,522 stroke incidents and 487,150 participants with 12,999 cases of stroke mortality). The follow-up duration varied from 5.5 to 26 years.

There was no significant publication bias based on the Egger test except that the evaluation of total meat with stroke incidence reached the significance threshold.

The average score for study quality assessed by the Newcastle‐Ottawa Scale was 7.29 (range 7-8) for studies on meat consumption and stroke incidence and 6.87 (range 6-8) for those on stroke mortality.

Results and conclusions:
The investigators found that a high total meat (red and processed meat) consumption resulted in a significantly higher risk of 18% [pooled relative risk = 1.18, 95% CI = 1.09-1.28, I2 = 0%] for total stroke incidence. Significantly means that there is an association with a 95% confidence.

The investigators found that a high red meat consumption resulted in a significantly higher risk of 11% [pooled relative risk = 1.11, 95% CI = 1.03-1.20, I2 = 0%] for total stroke incidence.

The investigators found that a high processed meat consumption resulted in a significantly higher risk of 17% [pooled relative risk = 1.17, 95% CI = 1.08-1.25, I2 = 0%] for total stroke incidence.

The investigators found that a high white meat consumption resulted in a significantly lower risk of 13% [pooled relative risk = 0.87, 95% CI = 0.78-0.97, I2 = 0%] for total stroke incidence.

The investigators found, however, no significant associations between consumption of total [RR = 0.97, 95% CI = 0.85-1.11, I2 = 0%] or red meat [RR = 0.87, 95% CI = 0.64-1.18, I2 = 70.9%] and stroke mortality. No significant associations because RR of 1 was found in the 95% CI of 0.64 to 1.18. RR of 1 means no risk/association.

The investigators found that a high total meat consumption was associated with an increased risk of 41% for hemorrhagic stroke [RR = 1.41, 95% CI = 1.08-1.84, I2 = 0%], but no significant association was found between a high total meat consumption and ischemic stroke [RR = 1.16, 95% CI = 0.94-1.43, I2 = 40.6%].

The investigators found a positive association between total meat consumption and stroke incidence, regardless of sex, number of cases and follow‐up duration.

The investigators found when stratified by adjustment variables, studies that adjusted for family history of myocardial infarction, fruit and vegetable intake and use of aspirin showed a statistically significant relationship between total meat intake and risk of stroke compared with other studies that did not include those as adjustment variables.

The investigators found that a high red meat consumption was associated with an increased risk of 24% for ischemic stroke [RR = 1.24, 95% CI = 1.05-1.46, I2 = 17.7%], but no significant association was found between a high red meat consumption and hemorrhagic stroke [RR = 1.11, 95% CI = 0.89-1.38, I2 = 0%].

The investigators found that a high processed meat consumption was linked to neither ischemic [RR = 1.10, 95% CI = 0.96-1.27, I2 = 11.4%] nor hemorrhagic stroke [RR = 1.19, 95% CI = 0.95-1.49, I2 = 8.10%].

The investigators concluded that higher consumption of red or processed meat is associated with an increase in the risk of stroke, while higher intake of white meat is related to a reduction in stroke incidence. Therefore, recommendations for replacing proportions of red and processed meat to white meat for the prevention of stroke may be considered in clinical practice.

Original title:
Role of Total, Red, Processed, and White Meat Consumption in Stroke Incidence and Mortality: A Systematic Review and Meta-Analysis of Prospective Cohort Studies by Kim K, Hyeon J, […], Park SM.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5634267/

Additional information of El Mondo:
Find more information/studies on meat consumption and cardiovascular diseases right here.

Objectives:
Dietary fiber intake, especially viscous soluble fiber, has been established as a means to reduce cardiometabolic risk factors. Whether this is true for blood pressure remains controversial. Therefore, this review article (meta-analysis) has been conducted.

Does viscous soluble fiber supplementation reduce cardiovascular disease risk?

Study design:
This review article included 22 (n = 1430) and 21 RCTs (N = 1343) for systolic blood pressure (SBP) and diastolic blood pressure (DBP), respectively.

5 types of viscous fiber supplementation were β-glucan from oats and barley, guar gum, konjac, pectin and psyllium.

Results and conclusions:
The investigators found viscous soluble fiber supplementation significantly reduced systolic blood pressure [MD = -1.59 mmHg, 95% CI = -2.72 to -0.46, I2 = 72%, p 0.01] and diastolic blood pressure [MD = -0.39 mmHg, 95% CI = -0.76 to -0.01, I2 = 67%, p 0.01] at a median dose of 8.7 g/day (1.45-30 g/day) over a median follow-up of 7-weeks.

The investigators found within the five fiber types, systolic blood pressure reductions were observed only for supplementation using psyllium fiber [MD = -2.39 mmHg, 95% CI = -4.62 to -0.17].

The investigators concluded 8.7 g/day viscous soluble fiber supplementation, particularly psyllium fiber during 7 weeks reduces systolic blood pressure (SBP) and diastolic blood pressure (DBP). Therefore, inclusion of viscous fiber to habitual diets may have additional value in reducing cardiovascular risk via improvement in blood pressure.

Original title:
The effect of viscous soluble fiber on blood pressure: A systematic review and meta-analysis of randomized controlled trials by Khan K, Jovanovski E, […], Vuksan V.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29153856

Additional information of El Mondo:
Find more information/studies on fiber consumption, hypertension and cardiovascular diseases right here.

Objectives:
Elevated cholesterol has been linked to cardiovascular disease in adults and preclinical markers of atherosclerosis in children, thus reducing saturated (SFA) and trans-fatty acids (TFA) intake from an early age may help to reduce cholesterol and the risk of cardiovascular disease later in life. The World Health Organization (WHO) is currently updating its guidance on SFA and TFA intake in adults and children. Therefore, this review article (meta-analysis) has been conducted.

Does a diet with low saturated fatty acids reduce cholesterol and blood pressure in children and adolescents between 2 to 19 years of age?

Study design:
This review article included 8 RCTs (5 trials had a duration of 1 year and 3 had a duration of ≥ 1year with a total of 2,430 individual children and adolescents between 2 to 19 years of age) and 3 cohort studies.

Minimum duration was 13 days for RCTs and one year for cohort studies.

Saturated fatty acids intake was assessed using 24hr dietary recalls in 4 trials, 3-day diet records in 3 trials and food frequency questionnaires and/or checklists in 2 trials.

No trials were identified meeting the inclusion criteria for trans-fatty acids.

Publication bias was not assessed as the number of trials found was not sufficient to conduct funnel plot analyses for any outcome measure.

Results and conclusions:
The investigators found compared with control diets, there was a highly statistically significant effect of reduced saturated fatty acids intake on total cholesterol [MD = -0.16 mmol/L, 95% CI = -0.25 to -0.07, I2 = 64%], LDL cholesterol [MD = -0.13 mmol/L, 95% CI = -0.22 to -0.03, I2 = 77%] and diastolic blood pressure [MD = -1.45 mmol/L, 95% CI = -2.34 to -0.56].
The effects on cholesterol were greatest among those in which saturated fatty acids was replaced primarily with PUFA or MUFA and when the intervention group achieved a reduction in saturated fatty acids to below 10% of total energy intake.

The investigators found subgroup analysis of the effect of the initial lipid status of the participants showed a significantly different effect of saturated fatty acids reduction on total cholesterol [p = 0.05] between trials involving normolipidaemic/mixed status children [MD -0.21 mmol/L, 95% CI = -0.31 to -0.12] vs hyperlipidaemic children [MD = -0.08 mmol/L, 95% CI = -0.15 to -0.01].

The investigators found subgroup analysis of the effect of the initial lipid status of the participants showed the reduction in LDL cholesterol (bad cholesterol) was greater among the trials conducted in normolipidaemic/mixed status [MD -0.21 mmol/L, 95% CI = -0.30 to -0.13] vs hyperlipidaemic children [MD = -0.02 mmol/L, 95% CI = -0.14 to -0.11].

The investigators found there were no significant associations observed for HDL cholesterol (good cholesterol), triglycerides or apolipoproteins A1 or B.

The investigators found there were no significant associations observed between reduced saturated fatty acids intake and weight, height, body mass index (BMI) or waist circumference.

The investigators found there was no evidence of adverse effects of reducing saturated fatty acids intake in children on micronutrient intakes, cognitive development or sexual maturation in the small number of trials reporting these outcomes.  

The investigators concluded a diet with low saturated fatty acids reduces total cholesterol, LDL cholesterol and diastolic blood pressure in children and adolescents between 2 to 19 years of age without evidence of adverse effects on growth and development. The greatest effect on cholesterol occurred when saturated fatty acids was replaced with PUFA or a mixture of PUFA/MUFA and when saturated fatty acids intake was less than 10% of total energy intake. Therefore, dietary guidelines for children and adolescents should continue to recommend diets low in saturated fat.

Original title:
Health effects of saturated and trans-fatty acid intake in children and adolescents: Systematic review and meta-analysis by Morenga L and Montez JM.

Link:
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0186672

Additional information of El Mondo:
Find more information/studies on fat consumption, body mass index, hypertension, cholesterol and cardiovascular diseases right here.  

A diet with saturated fatty acids intake less than 10% of total energy intake is a diet with less than 10 En% saturated fat.
A diet with less than 10 En% saturated fat is a diet that is largely made up of meals/products with less than 10 En% saturated fat. Practically, this means that all meals/products that you eat on a daily basis should on average contain less than 10 En% saturated fat. Check here which products contain less than 10 En% saturated fat.

Objectives:
Despite growing evidence for food-based dietary patterns' potential to reduce cardiovascular disease risk, knowledge about the amounts of food associated with the greatest change in risk of specific cardiovascular outcomes and about the quality of meta-evidence is limited. Therefore, this review article (meta-analysis) has been conducted.

Which food-based dietary patterns reduce risk of cardiovascular diseases, such as coronary heart disease (CHD), stroke and heart failure (HF)?

Study design:
This review article included 123 prospective cohort studies.

Results and conclusions:
The investigators found whole grains significantly reduced risk of coronary heart disease with 5% [RR = 0.95, 95% CI = 0.92-0.98]. Significantly means that there is an association with a 95% confidence.

The investigators found whole grains significantly reduced risk of heart failure with 4% [RR = 0.96, 95% CI = 0.95-0.97]. Significantly because RR of 1 was not found in the 95% CI of 0.95 to 0.97. RR of 1 means no risk/association.

The investigators found vegetables significantly reduced risk of coronary heart disease with 3% [RR = 0.97, 95% CI = 0.96-0.99]. Significantly means it can be said with a 95% confidence that a intake of vegetables really decreased the risk of getting coronary heart disease with 3%.  

The investigators found fruits significantly reduced risk of coronary heart disease with 6% [RR = 0.94, 95% CI = 0.90-0.97].

The investigators found vegetables significantly reduced risk of stroke with 8% [RR = 0.92, 95% CI = 0.86-0.98].

The investigators found fruits significantly reduced risk of stroke with 10% [RR = 0.90, 95% CI = 0.84-0.97].

The investigators found nuts non-significantly reduced risk of coronary heart disease with 33% [RR = 0.67, 95% CI = 0.43-1.05]. Non-significantly means that there is no association with a 95% confidence.

The investigators found fish consumption significantly reduced risk of stroke with 14% [RR = 0.86, 95% CI = 0.75-0.99].

The investigators found fish consumption significantly reduced risk of heart failure with 20% [RR = 0.80, 95% CI = 0.67-0.95].

The investigators found egg significantly increased risk of heart failure with 16% [RR = 1.16, 95% CI = 1.03-1.31].

The investigators found red meat significantly increased risk of coronary heart disease with 15% [RR = 1.15, 95% CI = 1.08-1.23].

The investigators found red meat significantly increased risk of stroke with 12% [RR = 1.12, 95% CI = 1.06-1.17].

The investigators found red meat significantly increased risk of heart failure with 8% [RR = 1.08, 95% CI = 1.02-1.14].

The investigators found processed meat significantly increased risk of coronary heart disease with 27% [RR = 1.27, 95% CI = 1.09-1.49].

The investigators found processed meat significantly increased risk of stroke with 17% [RR = 1.17, 95% CI = 1.02-1.34].

The investigators found processed meat significantly increased risk of heart failure with 12% [RR = 1.12, 95% CI = 1.05-1.19].

The investigators found sugar-sweetened beverages significantly increased risk of coronary heart disease with 17% [RR = 1.17, 95% CI = 1.11-1.23].

The investigators found sugar-sweetened beverages significantly increased risk of heart failure with 7% [RR = 1.07, 95% CI = 1.02-1.12].

The investigators found sugar-sweetened beverages significantly increased risk of stroke with 8% [RR = 1.08, 95% CI = 1.05-1.12].

The investigators found there were clear indications for non-linear dose-response relationships between whole grains, fruit, nuts, dairy and red meat and coronary heart disease.

The investigators concluded there is a relationship between food-based dietary patterns and risk of cardiovascular diseases, with an increased risk for consumption of eggs, red meat, processed meat and sugar-sweetened beverages and a decreased risk for consumption of whole grains, vegetables, fruit and fish.

Original title:
Food groups and risk of coronary heart disease, stroke and heart failure: A systematic review and dose-response meta-analysis of prospective studies by Bechthold A, Boeing H, […], Schwingshackl L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29039970

Additional information of El Mondo:
Find more information/studies on food groups and cardiovascular diseases right here. 

Objectives:
The therapeutic efficacy of coenzyme Q10 on patients with cardiac failure remains controversial. Therefore, this review article (meta-analysis) has been conducted.

Do patients with heart failure benefit from coenzyme Q10 supplements?

Study design:
This review article included a total of 14 RCTs with 1064 patients in coenzyme Q10 (treatment) group and 1085 patients in placebo (control) group.

Egger’s test results showed no significant evidence of publication bias in either endpoint.

Results and conclusions:
The investigators found compared with placebo, coenzyme Q10 supplementation significantly decreased mortality risk with 31% [RR = 0.69, 95% CI = 0.50 to 0.95, p = 0.02, I2 = 0%].

The investigators found a greater improvement in exercise capacity was established in patients who used coenzyme Q10 than in those who used placebo [SMD = 0.62, 95% CI = 0.02 to 0.30, p = 0.04, I2 = 54%].

The investigators found patients who used coenzyme Q10 and placebo associated with similar left heart ejection fraction [SMD = 0.14, 95% CI = -0.08 to 0.37, p = 0.22, I2 = 54%].

The investigators found no significant difference between coenzyme Q10 and placebo for NYHA classification [SMD = -0.70, 95% CI = -1.92 to 0.51, p = 0.26, I2 = 89%].

The investigators concluded in patients with heart failure, the administration of coenzyme Q10 results in lower mortality and improved exercise capacity compared with the effects of placebo treatment.

Original title:
Efficacy of coenzyme Q10 in patients with cardiac failure: a meta-analysis of clinical trials by Lei L and Liu Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5525208/

Additional information of El Mondo:
Find more information/studies on coenzyme Q10 and cardiovascular diseases right here. 

Objectives:
Several previous meta-analyses show a consistent inverse association between nut consumption and all-cause mortality, but the associations with cause-specific mortality remain uncertain. Therefore, this meta-analysis (review article) has been conducted.

Does nut consumption reduce all-cause and cause-specific mortality?

Study design:
This review article included 18 prospective cohort studies with 81,034 deaths.

Results and conclusions:
The investigators found random-effects meta-analysis of 18 studies with 81,034 deaths showed a significant reduced risk of 19% [summary RR = 0.81, 95% CI = 0.78-0.84] for all-cause mortality for high compared with low nut consumption. This significant reduced risk was broadly consistent within subgroups according to various study and population characteristics and within sensitivity analyses that took into account potential confounders.

The investigators found random-effects meta-analysis of 17 studies with 20,381 deaths showed a significant reduced risk of 25% [summary RR = 0.75, 95% CI = 0.71-0.79] for cardiovascular mortality for high compared with low nut consumption. This significant reduced risk was broadly consistent within subgroups according to various study and population characteristics and within sensitivity analyses that took into account potential confounders.

The investigators found random-effects meta-analysis of 14 studies with 10,438 deaths showed a significant reduced risk of 27% [summary RR = 0.73, 95% CI = 0.67-0.80] for coronary heart disease mortality for high compared with low nut consumption. This significant reduced risk was broadly consistent within subgroups according to various study and population characteristics and within sensitivity analyses that took into account potential confounders.

The investigators found random-effects meta-analysis of 13 studies with 4,850 deaths showed a significant reduced risk of 18% [summary RR = 0.82, 95% CI = 0.73-0.91] for stroke mortality for high compared with low nut consumption. This significant reduced risk was broadly consistent within subgroups according to various study and population characteristics and within sensitivity analyses that took into account potential confounders.

The investigators found random-effects meta-analysis of 11 studies with 21,353 deaths showed a significant reduced risk of 13% [summary RR = 0.87, 95% CI = 0.80-0.93] for cancer mortality for high compared with low nut consumption. This significant reduced risk was broadly consistent within subgroups according to various study and population characteristics and within sensitivity analyses that took into account potential confounders.

The investigators found peanut (5 studies) and tree nut (3 studies) consumption were similarly associated with mortality risks.

The investigators found dose-response analyses suggested evidence for nonlinear associations between nut consumption and mortality [p-nonlinearity 0.001 for all outcomes except cancer mortality], with mortality risk levelling off at the consumption of about 3 servings per week (12g/day).

The investigators concluded that nut consumption is associated with reduced all-cause and cause-specific mortality, with the strongest reduction for coronary heart disease (CHD) mortality. Both tree nuts and peanuts lower mortality and most of the survival benefits could be achieved at a relative low level of nut consumption (up to 12g/day).

Original title:
Nut consumption in relation to all-cause and cause-specific mortality: a meta-analysis 18 prospective studies by Chen GC, Zhang R, [...], Qin LQ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28875220

Additional information of El Mondo:
Find more information/studies on nut consumption, cancer, cardiovascular disease and stroke right here.
 

Objectives:
Anthocyanins are of interest due to their anti-oxidative and vasodilatory properties. Earlier reviews have shown that berries and other anthocyanin rich foods or extracts can improve vascular health. However, the effect of anthocyanins on vascular function has not yet been reviewed. Therefore, this review article (meta-analysis) has been conducted.

Does anthocyanin supplementation improve vascular function?

Study design:
This review article included 29 RCTs (15 were parallel and 14 were crossover designs).
Anthocyanin intakes ranged from 1 to 724 mg/day.
Most studies (n = 19) involved participants in the middle to older age group (mean age ≥ 40 years).
The number of participants that completed each study ranged from 10 to 146.
Intervention durations ranged from 1 h to 6 h in the acute studies and one week to six months in the chronic studies.

There was no publication bias.

Results and conclusions:
The investigators found compared to placebo-control, acute anthocyanin supplementation (1-8 h post consumption of anthocyanin doses between 7 and 724 mg) significantly improved FMD [SMD = 3.92%, 95% CI = 1.47 to 6.38, p = 0.002, I2 = 91.8%].
No improvements were observed in PAT-RHI [SMD = 0.08, 95% CI = -0.34 to 0.50, p = 0.71, I2 = 0%].
Collectively, (i.e., the pooling of studies using FMD and/or PAT-RHI) anthocyanins may improve vascular reactivity [overall SMD = 2.41, 95% CI = 0.91 to 3.91, p = 0.002, I2 = 92.6%].

The investigators found compared to placebo-control, acute anthocyanin supplementation (1-8 h post consumption of anthocyanin doses between 7 and 724 mg) also significantly improved arterial stiffness, using PWV [SMD = -1.27 m/s, 95% CI = -1.96 to -0.58, p = 0.000, I2 = 17.9%].

The investigators found pulse wave velocity was improved following acute anthocyanin supplementation only [SMD = -1.27 m/s, 95% CI = -1.96 to -0.58, p = 0.000, I2 = 17.8%]. 

The investigators found compared to placebo-control, chronic anthocyanin supplementation (one week to six months and used anthocyanin doses of 12 to 320 mg/day) significantly improved FMD [SMD = 0.84%, 95% CI = 0.55 to 1.12, p = 0.000, I2 = 62.5%].
Collectively (i.e., the pooling of studies using FMD and/or PAT-RHI), chronic anthocyanin supplementation may improve vascular reactivity [overall SMD = 0.77, 95% CI = 0.37 to 1.16, p = 0.000, I2 = 85.3%].

The investigators concluded that both acute and chronic anthocyanin supplementation improve vascular health, particularly with respect to vascular reactivity measured by FMD. However, more research is required to determine the optimal dosage and the long-term effects of anthocyanin consumption.

Original title:
The Effect of Anthocyanin-Rich Foods or Extracts on Vascular Function in Adults: A Systematic Review and Meta-Analysis of Randomised Controlled Trials by Fairlie-Jones L, Davison K, […], Hill AM.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5579701/

Additional information of El Mondo:
Find more information/studies on flavonoids and cardiovascular diseases right here.  

Objectives:
Although epidemiological studies have examined the role of chocolate in preventing cardiometabolic disease, the results remain inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Does chocolate consumption reduce risk of coronary heart disease (CHD), stroke and diabetes?

Study design:
This review article included 14 prospective cohort studies, with 508,705 participants from six countries and 7,267 coronary heart disease (CHD) cases, 8,197 stroke cases and 13,271 diabetes cases.
The follow-up duration of the studies ranged from 5 to 16 years.
One serving was defined as 30g of chocolate.
The majority of chocolate consumed in the included studies was milk or dark chocolate.

Results and conclusions:
The investigators found in 6 cohort studies for the highest versus lowest intake of chocolate a significant reduced risk of 10% for coronary heart disease [pooled RR = 0.90, 95% CI = 0.82-0.97, I2 = 24.3%, p = 0.25]. Leave-one-out sensitivity analysis had no significant influence on the pooled results.

The investigators found regarding CHD subtype, a significant reduced risk of 14% [RR = 0.86, 95% CI = 0.77-0.96] for myocardial infarction.

The investigators found for studies with follow-up duration of 10 years a significant reduced risk of 28% for coronary heart disease [RR = 0.72, 95% CI = 0.57-0.92].

The investigators found for studies with follow-up duration of ≥10 years a significant reduced risk of 8% for coronary heart disease [RR = 0.92, 95% CI = 0.86-0.99].

The investigators found in dose-response meta-analysis of 5 studies a curvilinear association between chocolate consumption and risk of coronary heart disease [p for nonlinearity = 0.006].

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 6% for coronary heart disease for 1 serving (30g) chocolate per week [RR = 0.94, 95 CI = 0.90-0.99].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 9% for coronary heart disease for 3 servings (90g) chocolate per week [RR = 0.91, 95 CI = 0.85-0.97].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 11% for coronary heart disease for 7 servings (210g) chocolate per week [RR = 0.89, 95 CI = 0.83-0.95].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 12% for coronary heart disease for 10 servings (300g) chocolate per week [RR = 0.88, 95 CI = 0.81-0.95].   

The investigators found in 8 reports from 7 studies for the highest versus lowest level of chocolate consumption a significant reduced risk of 16% for stroke [pooled RR = 0.84, 95% CI = 0.78-0.90, I2 = 0%, p = 0.49]. The pooled risk of total stroke was not obviously modified in the sensitivity analysis by excluding one study at a time
Egger’s test suggested the presence of publication bias [p = 0.008]. However, after introducing the “trim and fill” method to adjust this bias, the overall risk estimate remained significant in favor of chocolate intake [RR = 0.86, 95% CI = 0.79-0.92].

The investigators found with regard to stroke subtypes, a significant reduced risk of 13% [RR = 0.87, 95% CI = 0.78-0.96] for cerebral infarction and a significant reduced risk of 17% [RR = 0.83, 95% CI = 0.71-0.97] for hemorrhagic stroke.

The investigators found in the stratified analysis by gender, a significant reduced risk of 13% of total stroke for male [RR = 0.87, 95% CI = 0.79-0.97] and a significant reduced risk of 16% of total stroke for female [RR = 0.84, 95% CI = 0.74-0.94].

The investigators found a significant reduced risk of 44% for studies with follow-up durations of 10 years [RR = 0.56, 95% CI = 0.37-0.85].

The investigators found a significant reduced risk of 15% for studies with follow-up durations of ≥10 years [RR = 0.85, 95% CI = 0.79-0.91].

The investigators found in 7 reports from 6 studies a nonlinear correlation between chocolate intake and risk of stroke [p for nonlinearity = 0.001].

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 9% for stroke for 1 serving chocolate per week [RR = 0.91, 95% CI = 0.86-0.97].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 13% for stroke for 3 servings chocolate per week [RR = 0.87, 95% CI = 0.81-0.94].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 15% for stroke for 7 servings chocolate per week [RR = 0.85, 95% CI = 0.76-0.93].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 17% for stroke for 10 servings chocolate per week [RR = 0.83, 95% CI = 0.72-0.94].   

The investigators found in 4 studies using “trim and fill” method, for the highest versus lowest intake of chocolate, a non-significant reduced risk of 8% for diabetes [pooled RR = 0.92, 95% CI = 0.78-1.08].

The investigators found in stratified analysis by sex, a significant reduced risk of 21% [RR = 0.79, 95% CI = 0.65-0.96] for men and a non-significant reduced risk of 8% [RR = 0.92, 95% CI = 0.72-1.17] for women.
Similarly, the risks of diabetes were not different between subsets of studies with follow-up durations of below or over 10 years [p for interaction = 0.51].

The investigators found in dose-response meta-analysis of 6 reports, a curvilinear association between chocolate intake and risk of diabetes [p for nonlinearity 0.001].

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 20% for diabetes for 1 serving chocolate per week [RR = 0.80, 95% CI = 0.71-0.91]. Significant means that there is an association with a 95% confidence.

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 24% for diabetes for 3 servings chocolate per week [RR = 0.76, 95% CI = 0.63-0.91]. Significant because RR of 1 was not found in the 95% CI of 0.63 to 0.91. RR of 1 means no risk/association.

The investigators found in dose-response meta-analysis, compared with no intake, a non-significant reduced risk of 17% for diabetes for 7 servings chocolate per week [RR = 0.83, 95% CI = 0.67-1.03]. Non-significant means it cannot be said with a 95% confidence that 7 servings chocolate per week really decreased the risk of diabetes with 17%.

The investigators found in dose-response meta-analysis, compared with no intake, a non-significant reduced risk of 11% for diabetes for 10 servings chocolate per week [RR = 0.89, 95% CI = 0.69-1.16].   

The investigators found in general, the dose-response pattern was J-shaped and the peak reduction in diabetes risk occurred at an intake of 2 servings/week [RR = 0.75, 95% CI = 0.63-0.89], with no protective effects observed when consuming chocolate > 6 servings/week.

The investigators concluded that chocolate consumption confers reduced risks of coronary heart disease, stroke and diabetes. Consuming chocolate in moderation (1-6 servings/week or 30-180g) may be optimal for the prevention of these burdensome diseases. However, additional large prospective studies are required to confirm the observed benefits of chocolate in populations with different characteristics and to establish the optimum frequency of chocolate intake for preventing cardiometabolic disease.

Original title:
Chocolate Consumption and Risk of Coronary Heart Disease, Stroke, and Diabetes: A Meta-Analysis of Prospective Studies by Yuan S, Li X, […], Lu J.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537803/

Additional information of El Mondo:
Find more information/studies on chocolate, diabetes and cardiovascular diseases right here.

Objectives:
The clinical benefits of perioperative antioxidant vitamin therapy in cardiac patients remain controversial. Therefore, this review article (meta-analysis) has been conducted.

Do patients undergoing cardiac surgery benefit from perioperative antioxidant vitamin therapy?

Study design:
This review article included 12 RCTs with 1584 cardiac patients.

Results and conclusions:
The investigators found compared with placebo or no antioxidant vitamin therapy that administration of antioxidant vitamin therapy resulted in a significant reduction:
-in postoperative atrial fibrillation (POAF) [RR = 0.55, 95% CI = 0.42 to 0.73, p  0.0001];
-duration of hospital stay [MD = -0.68, 95% CI = -0.98 to -0.39, p  0.00001];
-intensive care unit length of stay [MD = -0.21, 95% CI = -0.30 to -0.12, p  0.00001] and;      
-intubation time [MD = -2.41, 95% CI = -3.83 to -0.98, p = 0.001].

The investigators also found a trend towards a decrease in postoperative complications [RR = 0.72, 95% CI = 0.48-1.08, p = 0.11] and duration of postoperative atrial fibrillation [MD = -1.950, 95% CI = -3.28 to 0.29, p = 0.10].

The investigators concluded that perioperative antioxidant vitamin therapy in patients undergoing cardiac surgery reduces the incidence of postoperative atrial fibrillation, duration of hospital stay, intensive care unit length of stay and intubation time.

Original title:
The clinical benefits of perioperative antioxidant vitamin therapy in patients undergoing cardiac surgery: a meta-analysis by Geng J, Qian J, […], Shen Z.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28645181

Additional information of El Mondo:
Find more information/studies on antioxidant and cardiovascular diseases right here.

Objectives:
Studies implicate choline and betaine metabolite trimethylamine N-oxide (TMAO) in cardiovascular disease (CVD). Therefore, this review article (meta-analysis) has been conducted.

Is there an association between choline and betaine dietary intake and cardiovascular disease?

Study design:
This review article included a total of 6 prospective cohort studies comprising 18,076 incident cardiovascular disease events, 5,343 cardiovascular disease deaths among 184,010 participants.

There was no evidence for heterogeneity among studies.
Only 2 studies provided data on phosphatidylcholine and cardiovascular disease mortality.

Results and conclusions:
The investigators found in random effects meta-analysis, incident cardiovascular disease was not associated with choline [RR = 1.00, 95% CI = 0.98-1.02] or betaine [RR = 0.99, 95% CI = 0.98-1.01] dietary intake.
Results did not vary by study outcome (incident coronary heart disease, stroke, total cardiovascular disease).

The investigators found random effects meta-analysis did not support an association between choline and cardiovascular disease mortality [RR = 1.09, 95% CI = 0.89-1.35], but one study supported a positive association and there was significant heterogeneity [I2 = 84%, p 0.001].

The investigators concluded that there is no association between dietary choline/betaine intake with incident cardiovascular disease, but further research into choline and cardiovascular disease mortality are needed.

Original title:
Dietary Choline and Betaine and Risk of CVD: A Systematic Review and Meta-Analysis of Prospective Studies by Meyer KA and Shea JW.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28686188

Additional information of El Mondo:
Find more information/studies on choline and cardiovascular diseases right here.

Objectives:
Controversy exists on the association between alcohol consumption and risk of heart failure (HF). Therefore, this review article (meta-analysis) has been conducted.

Is there an association between alcohol consumption and risk of heart failure?

Study design:
This review article included a total of 13 prospective cohort studies, with 13,738 heart failure cases among 355,804 participants.

Results and conclusions:
The investigators found light alcohol drinking (0.1-7 drinks/week) significantly reduced risk of heart failure with 14% [RR = 0.86, 95% CI = 0.81-0.90]. However, there was no statistically significant association between moderate (7.1-14 drinks/week), high (14.1-28 drinks/week), or heavy (>28 drinks/week) alcohol consumption and heart failure risk.

The investigators found former drinking significantly increased risk of heart failure with 22% [RR = 1.22, 95% CI = 1.11-1.33] compared with never or occasional drinking.

The investigators concluded that light alcohol drinking (0.1-7 drinks/week) is associated with a lower risk of heart failure, while former drinking is associated with a higher risk of heart failure.

Original title:
Alcohol consumption and risk of heart failure: Meta-analysis of 13 prospective studies by Susanna C. Larsson, […], Alicja Wolk

Link:
http://www.sciencedirect.com/science/article/pii/S0261561417301681

Additional information of El Mondo:
Find more information/studies on alcohol consumption and cardiovascular diseases right here.