Nutrition and health

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:
Available studies in the literature on the selenium levels in Alzheimer's disease (AD) are inconsistent with some studies reporting its decrease in the circulation, while others reported an increase or no change as compared to controls. Therefore, this meta-analysis (review article) has been conducted.

Do lower circulatory (plasma/serum and blood), erythrocyte and cerebrospinal fluid (CSF) selenium levels increase Alzheimer's disease risk?

Study design:
This review article included 12 case-control/observational studies reporting selenium concentrations in Alzheimer's disease and controls.

Results and conclusions:
The investigators found random-effects meta-analysis indicated a decrease in circulatory [SMD = -0.44], erythrocellular [SMD = -0.52] and cerebrospinal fluid [SMD = -0.14] selenium levels in Alzheimer's disease patients compared to controls

The investigators found stratified meta-analysis demonstrated that the selenium levels were decreased in both the subgroups with [SMD = -0.55] and without [SMD = -0.37] age matching between Alzheimer's disease and controls.

The investigators also found a direct association between decreased selenium levels and glutathione peroxidase (GPx) in Alzheimer's disease.

The investigators concluded that circulatory selenium concentration is significantly lower in Alzheimer's disease patients compared to controls and this decrease in selenium is directly correlated with an important antioxidant enzyme, the glutathione peroxidase, in Alzheimer's disease.

Original title:
A systematic review and meta-analysis of the circulatory, erythrocellular and CSF selenium levels in Alzheimer's disease: A metal meta-analysis (AMMA study-I) by Reddya VS, Bukkeb S, […], Pandeye AK.

Link:
http://www.sciencedirect.com/science/article/pii/S0946672X1630205X%20

Additional information of El Mondo:
Find more information/studies on selenium and dementia 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:
Does higher protein intake increase bone mineral density?

Study design:
This review article included 6 RCTs and 20 prospective cohort studies.
There were no adverse effects of higher protein intakes.
Studies were heterogeneous and confounding could not be excluded.

Results and conclusions:
The investigators found moderate evidence suggested that higher protein intake may have a protective effect on lumbar spine bone mineral density compared with lower protein intake [net percentage change = 0.52%, 95% CI = 0.06%-0.97%, I2 = 0%, n = 5] but had no effect on total hip, femoral neck, or total body bone mineral density or bone biomarkers.

The investigators concluded that higher protein intake may have a protective effect on lumbar spine bone mineral density. May have because studies were heterogeneous and confounding could not be excluded. Therefore, high-quality, long-term studies are needed to clarify dietary protein's role in bone health.

Original title:
Dietary protein and bone health: a systematic review and meta-analysis from the National Osteoporosis Foundation by Shams-White MM, Chung M, […], Weaver CM.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28404575

Additional information of El Mondo:
Find more information/studies on protein and elderly right here.

A higher protein diet is a diet with 20-35 En% protein. The easiest way to meet a diet with 20-35 En% protein is to choose food items/meals with also 20-35 En% protein. Check here which products contain 20-35 En% protein.
 

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:
Current studies evaluating the association of tea consumption and bone mineral density (BMD) have yielded inconsistent findings. Therefore, this meta-analysis (review article) has been conducted.

Does tea consumption increase bone mineral density?

Study design:
This review article included 4 cohort, 1 case-control and 8 cross-sectional studies including a total of 12,635 cases (6,059 in the tea consumption group and 6,576 individuals in non-tea consumption group).

Results and conclusions:
The investigators found tea consumption significantly reduced the occurrence of low bone mass with 34% [OR  =  0.66, 95% CI  =  0.47-0.94, p =  0.02].

The investigators found tea consumption significantly yielded higher mineral densities in several bones, including:
-the lumbar spine [standardized mean difference (SMD) = 0.19, 95% CI = 0.08-0.31, p  =  0.001];
-hip [SMD = 0.19, 95% CI = 0.05-0.34, p  =  0.01];
-femoral neck [mean difference (MD) = 0.01, 95% CI = 0.00-0.02, p  =  0.04];
-Ward triangle [MD = 0.02, 95% CI = 0.01-0.04, p  =  0.001] and;
-greater trochanter [MD = 0.03, 95% CI = 0.02-0.04, p  0.00001]
than the non-tea consumption group.

The investigators concluded that tea consumption increases bone mineral density, especially in the lumbar spine, hip, femoral neck, Ward triangle and greater trochanter, which can prevent bone loss.

Original title:
Updated association of tea consumption and bone mineral density: A meta-analysis by Zhang ZF, Yang JL, [...], Liu ZX.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5371490/

Additional information of El Mondo:
Find more information/studies on tea consumption and elderly 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.

Objectives:
Is there a relationship between serum 25(OH)D (vitamin D blood level) and mortality risk in the general population?

Study design:
This review article included 14 prospective cohort studies that involved 5562 deaths out of 62548 individuals.
In the parametric model, which is based on 11 studies and 59231 individuals, the lowest quantile as the reference category has been used.

Evidence of heterogeneity for the RR was apparent when highest were compared with lowest categories [p = 0.008, I2 = 58%].

There was no evidence of publication bias.

Results and conclusions:
The investigators found for “highest compared with lowest” categories of 25(OH)D, a significant reduced risk of 29% for mortality [RR = 0.71, 95% CI = 0.50-0.91].

The investigators found in the parametric model, the estimated summary RRs of mortality were 0.86 [95% CI = 0.82-0.91], 0.77 [95% CI = 0.70-0.84] and 0.69 [95% CI = 0.60-0.78] for individuals with an increase of 12.5, 25 and 50 nmol 25(OH)D serum values/L, respectively, from a median reference category of ∼27.5 nmol/L.
However, no significant decrease in mortality was found above ∼87.5 nmol/L.

The investigators concluded there is a nonlinear decrease in mortality risk as circulating 25(OH)D increases, with optimal concentrations ∼75-87.5 nmol/L. Because many adults do not achieve these 25(OH)D values, large prospective randomized trials are urgently needed to investigate whether vitamin D supplementation is able to reduce mortality risk in the general population.

Original title:
Vitamin D deficiency and mortality risk in the general population: a meta-analysis of prospective cohort studies by Zittermann A, Iodice S, [...], Gandini S.

Link:
http://ajcn.nutrition.org/content/95/1/91.full

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

Objectives:
Low glycaemic index (GI) diets are beneficial in the management of hyperglycemia. Cardiovascular diseases are the major cause of mortality in diabetes therefore it is important to understand the effects of GI on blood lipids. Therefore, this review article has been conducted.

Does a low GI diet lower the cholesterol levels?

Study design:
This review article included 28 RCTs comparing low with high GI diets over at least 4 weeks. These 28 RCTs contained 1272 participants with studies ranged from 6 to 155 participants, one was powered on blood lipids and 3 had adequate allocation concealment.

Results and conclusions:
The investigators found that compared to high GI diet low GI diet significantly reduced total cholesterol by 0.13 mmol/L [95% CI = -0.22 to -0.04, p = 0.004, 27 trials, 1441 participants]. Significantly means, it can be said with 95% confidence that low GI diet really lowered the total cholesterol levels with 0.13 mmol/L.

The investigators found that compared to high GI diet low GI diet significantly reduced LDL-cholesterol by 0.16 mmol/L [95% CI = -0.24 to -0.08, p 0.0001, 23 studies, 1281 participants]. Significantly, because the p-value was less than 0.05.

The investigators found subgroup analyses suggested that reductions in LDL-cholesterol were greatest in studies of shortest duration and greatest magnitude of GI reduction. Furthermore, lipid improvements appeared greatest and most reliable when the low GI intervention was accompanied by an increase in dietary fiber.

The investigators found sensitivity analyses, removing studies without adequate allocation concealment, lost statistical significance but retained suggested mean falls of 0.10 mmol/L in both.

The investigators found no effects on HDL-cholesterol [MD = -0.03 mmol/L, 95% CI = -0.06 to 0.00, I2 = 0%], or triglycerides [MD was 0.01 mmol/L, 95% CI = -0.06 to 0.08, I2 = 0%].

The researchers concluded that low GI diets reduce total and LDL-cholesterol (bad cholesterol) but had no effect on HDL-cholesterol (good cholesterol) or triglycerides.

Original title:
Low glycemic index diets and blood lipids: A systematic review and meta-analysis of randomized controlled trials by Goff LM, Cowland DE, [...], Frost GS.

Link:
http://www.sciencedirect.com/science/article/pii/S0939475312001524

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

High LDL-cholesterol levels and high triglyceride levels increase the risk of getting cardiovascular diseases whereas high HDL-cholesterol levels decrease the risk of getting cardiovascular diseases.

A low GI diet is a diet with a GI value of 55 or lower.

Objectives:
Recent evidence has suggested that flavonoid and lignan intake may be associated with decreased risk of chronic and degenerative diseases. Therefore, this review article (meta-analysis) has been conducted.

Does dietary flavonoid intake reduce risk of all-cause and cardiovascular disease mortality?

Study design:
This review article included 22 prospective cohort studies.

Results and conclusions:
The investigators found when compared with lower consumption, high consumption of total flavonoids was associated with a significant decreased risk of 26% for all-cause mortality [risk ratio = 0.74, 95% CI = 0.55-0.99].

The investigators found a 100-mg/day increment in dietary total flavonoids intake led to a (linear) decreased risk of 6% and 4% of all-cause and cardiovascular disease mortality, respectively.

The investigators found among flavonoid classes, significant results were obtained for intakes of flavonols, flavones, flavanones, anthocyanidins and proanthocyanidins.

The investigators found limited evidence was available on lignans intake and all-cause mortality.

The investigators concluded that higher dietary flavonoids intakes - at least 100-mg/day of flavonols, flavones, flavanones, anthocyanidins or proanthocyanidins - are associated with decreased risk of all-cause and cardiovascular disease mortality.

Original title:
Dietary Flavonoid and Lignan Intake and Mortality in Prospective Cohort Studies: Systematic Review and Dose-Response Meta-Analysis by Grosso G, Micek A, […], Giovannucci EL.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28472215

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

Objectives:
Does soy isoflavone reduce the frequency and severity of hot flashes?

Study design:
This review article included 19 trials (13 included hot flash frequency, of which 10 for severity and 3 for composite scores).
17 trials were selected for meta-analyses to clarify the effect of soybean isoflavones on hot flash frequency (13 trials) and severity (9 trials).

Results and conclusions:
The investigators found intake of soy isoflavones (median = 54 mg aglycone equivalents) for 6 weeks to 12 months significantly reduced the frequency (combined fixed-effect and random effects model) of hot flashes by 20.6% [95% CI = -28.38 to -12.86, p 0.00001] compared with placebo [p heterogeneity = 0.0003, I2 = 67% for random effects model].

The investigators also found isoflavones significantly reduced hot flash severity by 26.2% [95% CI = -42.23 to -10.15, p = 0.001] compared with placebo [p heterogeneity 0.00001, I2 = 86% for random effects model].

The investigators found isoflavone supplements providing more than 18.8 mg of genistein (the median for all studies) were more than twice as potent at reducing hot flash frequency than lower genistein supplements.

The investigators concluded soy isoflavone supplements (54 mg per day for 6 weeks to 12 months), derived by extraction or chemical synthesis, are significantly more effective than placebo in reducing the frequency and severity of hot flashes. Additional studies are needed to further address the complex array of factors that may affect efficacy, such as dose, isoflavone form, baseline hot flash frequency and treatment duration.

Original title:
Extracted or synthesized soybean isoflavones reduce menopausal hot flash frequency and severity: systematic review and meta-analysis of randomized controlled trials by Taku K, Melby MK, […], Messina M.

Link:
http://journals.lww.com/menopausejournal/Abstract/2012/07000/Extracted_or_synthesized_soybean_isoflavones.11.aspx

Additional information of El Mondo:
Find more studies/information on elderly and isoflavones right here.
 

Objectives:
There is an ongoing debate on the involvement of systemic copper (Cu) dysfunctions in Alzheimer's disease (AD) and clinical studies comparing Cu levels in serum, plasma and cerebrospinal fluid (CSF) of AD patients with those of healthy controls have delivered non-univocal and often conflicting results. Therefore, this review article has been conducted.

Does blood level of copper increase in Alzheimer’s disease?

Study design:
This review article included 26 studies including a pooled total of 761 AD subjects and 664 controls for serum Cu studies, 205 AD subjects and 167 controls for plasma Cu and of 116 AD subjects and 129 controls for CSF Cu.

Results and conclusions:
The investigators found Alzheimer's disease patients have higher levels of serum copper than healthy controls. Plasma data did not allow conclusions, due to their high heterogeneity, but the meta-analysis of the combined serum and plasma studies confirmed higher copper levels in Alzheimer's disease patients. 

The investigators found the analysis of CSF data revealed no difference between Alzheimer's disease patients and controls.

The investigators concluded Alzheimer's disease patients have higher levels of serum and plasma copper than healthy controls.

Original title:
Copper in Alzheimer's disease: a meta-analysis of serum, plasma, and cerebrospinal fluid studies by Bucossi S, Ventriglia M, […], Squitti R.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/21187586

Additional information of El Mondo:
Find more information/studies on copper and dementia right here.

Objectives:
The association between dietary vitamin K intake and the risk of fractures is controversial. Therefore, this meta-analysis (review article) has been conducted.

Does dietary vitamin K intake reduce risk of fractures?

Study design:
This review article included 4 cohort studies and 1 nested case-control study, including 80,982 total subjects and 1114 fracture cases.

The fractures were assessed using confirmed self-reported, medical and radiological report. Dietary vitamin K intake was assessed with a food-frequency questionnaire (FFQ) in 4 studies, only 1 study used 4-day or 7-day food record.
Vitamin K intake in all included studies refers exclusively to the intake of phylloquinone (vitamin K1), which is the predominant form of vitamin K in foods.
All subjects were more than 30 years old.
Duration of follow-up for the included studies ranged from 6.9 to 10 years.
Most studies provided RRs that were adjusted for age, BMI, BMD, physical activity, vitamin D and calcium intake, smoking and alcohol consumption.

The Begg and Egger tests did not show any substantial asymmetry (p  =  0.50 for Begg test and p  =  0.32 for Egger tests). Further trim and filled meta-analysis showed that there were no trimming data added.

Results and conclusions:
The investigators found for highest vs. the lowest dietary vitamin K intake a significant reduced risk of 22% [RR = 0.78, 95% CI = 0.56-0.99, I2  =  59.2%, p  = 0 .04] for fractures.

The investigators found for every increment of 50μg dietary vitamin K intake per day a significant reduced risk of 3% [RR  = 0.97, 95% CI = 0.95-0.99, I2  =  25.9%, p  = 0 .25] for fractures.

The investigators found a significant reduced risk of 24% [RR = 0.76, 95% CI = 0.58-0.93, I2  =  59.2%, p  = 0 .04] for fractures in studies with more than 10 years of follow-up.

The investigators concluded that higher dietary vitamin K intake; at least 50μg dietary vitamin K intake per day decreases the risk of fractures. This review article offers additional evidence on the relationship between dietary vitamin K intake and risk of fractures. The benefit of vitamin K should be confirmed in future well-designed prospective cohort studies and clinical trials.

Original title:
Vitamin K intake and the risk of fractures: A meta-analysis by Hao G, Zhang B, [...], Cao X.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5413254/

Additional information of El Mondo:
Find more information/studies on vitamin K and elderly right here.
 

Objectives:
In view of the vital role of oxidative stress in the pathogenesis of Alzheimer's disease (AD), the potential of antioxidant supplements to prevent AD have gained much interest, while there are conflicting results on this topic in recent years. Therefore, this review article has been conducted.

Does dietary intake of vitamin C and E and β-carotene decrease risk of Alzheimer's disease?

Study design:
This review article included 7 articles (dietary intake, but no supplements).

Results and conclusions:
The investigators found a significant decreased risk for Alzheimer disease of 24% [pooled relative risk = 0.76 95% CI = 0.67-0.84] for dietary intake of vitamin E and of 17% [pooled relative risk = 0.83, 95% CI = 0.72-0.94] for dietary intake of vitamin C.

However, the investigators found a non-significant decreased risk of 12% [pooled relative risk = 0.88, 95% CI = 0.73-1.03] for dietary intake of β-carotene.

The investigators concluded dietary intakes of vitamin C and E lower the risk of Alzheimer's disease, with vitamin E exhibiting the most pronounced protective effects. The findings will be of significance to the prevention and interventional treatment of Alzheimer's disease.

Original title:
Dietary intakes of vitamin E, vitamin C, and β-carotene and risk of Alzheimer's disease: a meta-analysis by Li FJ, Shen L and Ji HF.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/22543848

Additional information of El Mondo:
Find more information/studies on vitamin C and E and carotenoids right here. 

Objectives:
Manganese (Mn) is one of the most studied environmental heavy metals linked to Alzheimer’s disease (AD). However, it remains unclear whether serum manganese levels are associated with Alzheimer’s disease and mild cognition impairment (MCI, a prodromal stage of AD). Therefore, this meta-analysis (review article) has been conducted.

Does a lower serum manganese level increase risk of cognitive decline?

Study design:
This review article included 17 studies, involving 836 cases and 1254 health controls (HC).

The sample size of the included studies ranged from 8 to 758. The average age of the patient groups ranged from 66.2 to 87.0 years. The proportion of female patients ranged from 33% to 80%.

Strong heterogeneity existed among the studies. Heterogeneity was not due to methods for measuring manganese levels, geographic locations, age and gender of patients.

There was no publication bias in the present meta-analysis evaluated by the Egger’s test (p = 0.258) and Begg’s test (p = 0.107).

Results and conclusions:
The investigators found random-effects meta-analysis showed that patients with Alzheimer’s disease had significantly reduced serum manganese levels compared with health control subjects [SMD = -0.39, 95% CI = -0.71 to -0.08, p = 0.015].

The investigators found mild cognition impairment individuals had a tendency toward reduced serum manganese levels compared with health control subjects [SMD = -0.31, 95% CI = -0.70 to 0.08, p = 0.117].

The investigators found a significant decrease in serum manganese levels in patients with cognitive impairment (including both AD patients and MCI patients) [SMD = -0.37, 95% CI = -0.60 to -0.13, p = 0.002].

The investigators found no significant differences between Alzheimer’s disease and mild cognition impairment patients in serum levels [SMD = 0.24, 95% CI = -0.23 to 0.72, p = 0.310].

The investigators concluded that the serum manganese levels are lower in Alzheimer’s disease patients and manganese deficiency may be a risk factor for Alzheimer’s disease. However, the results should be interpreted with caution due to the high heterogeneity of the studies.

Original title:
Association of Serum Manganese Levels with Alzheimer’s Disease and Mild Cognitive Impairment: A Systematic Review and Meta-Analysis by Du K, Liu M, [...], Wei M.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5372894/

Additional information of El Mondo:
Find more information/studies on manganese and elderly right here.
 

Objectives:
The association between elevated serum phosphorus concentration and cardiovascular or all-cause mortality yielded conflicting results. Therefore, this review article (meta-analysis) has been conducted.

Does an elevated serum phosphorus concentration increase cardiovascular and all-cause mortality in the general population?

Study design:
This review article included 6 prospective cohort studies involving 120,269 subjects.

Results and conclusions:
The investigators found when compared the highest with the reference concentration of serum phosphorus, a significant increased risk of 36% for cardiovascular mortality [pooled RR = 1.36, 95% CI = 1.07-1.72]. Significant because RR of 1 was not found in the 95% CI of 1.07 to 1.72. RR of 1 means no risk/association.

The investigators found when compared the highest with the reference concentration of serum phosphorus, a significant increased risk of 33% for all-cause mortality [pooled RR = 1.33, 95% CI = 1.15-1.58]. Significant means that there is an association with a 95% confidence.

The investigators found stratified analyses revealed that elevated serum phosphorus significantly increased all-cause mortality risk with 33% among men [RR 1.33, 95% CI = 1.11-1.60], but not in women [RR = 1.09, 95% CI = 0.89-1.33].

The investigators concluded elevated serum phosphorus concentration is independently associated with excessive risk of cardiovascular and all-cause mortality in the general population without chronic kidney disease. Serum phosphorus on all-cause mortality risk appears to be pronounced in men but exhibits no clear effect on women. However, gender difference of elevated serum phosphorus on mortality risk should be verified by more prospective cohort studies.

Original title:
Serum phosphorus, cardiovascular and all-cause mortality in the general population: A meta-analysis by Bai W, Li J and Liu J.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/27475981

Additional information of El Mondo:
Find more studies/information on elderly and phosphorus right here.

Objectives:
Increased dietary potassium intake is thought to be associated with low blood pressure (BP). Whether potassium supplementation may be used as an antihypertensive agent is a question that should be answered. Therefore, this review article (meta-analysis) has been conducted.

Does potassium supplementation reduce blood pressure among patients with essential hypertension (SBP ≥140 mmHg and DBP ≥90 mmHg)?

Study design:
This review article included 23 trials (9 parallel and 14 crossover randomized placebo-controlled clinical trials with a minimum of 4 weeks of therapy to ensure that the intervention had sufficient time to produce an effect) involving 1,213 patients with essential hypertension (SBP ≥140 mmHg and DBP ≥90 mmHg).

The result of meta-regression revealed that the association between potassium dosage, follow-up period and mean age were not statistically significant; therefore they did not play an important role in the heterogeneity across studies.

There was no publication bias.

Results and conclusions:
The investigators found that potassium supplementation significantly reduced systolic blood pressure (SBP) of patients with essential hypertension with 4.25 mmHg [95% CI = -5.96 to -2.53, I2 = 41%].

The investigators found that potassium supplementation significantly reduced diastolic blood pressure (DBP) of patients with essential hypertension with 2.53 mmHg [95% CI = -4.05 to -1.02, I2 = 65%].

The investigators found in 8 RCTs when compared to baseline, the mean changes in systolic blood of patients with essential hypertension was -8.89 mmHg [95% CI = -13.67 to -4.11] significantly higher in the intervention group (group taking potassium supplements) than the control group. 

The investigators found in 8 RCTs when compared to baseline, the mean changes in diastolic blood pressure of patients with essential hypertension was -6.42 mmHg [95% CI = -10.99 to -1.84] significantly higher in the intervention group (group taking potassium supplements) than the control group. 

The investigators found in subgroup analysis that the mean difference in systolic blood of patients with essential hypertension was -2.64 mmHg [95% CI = -5.25 to -0.03] in America, -4.56 mmHg [95% CI = -6.51 to -2.62) in Europe and -5.21 mmHg [95% CI = -9.63 to -0.79] in Asia.

The investigators found a dose-response relationship between potassium intake and reduction in systolic and diastolic blood pressure (low-dose (50 mmol/day), moderate-dose (50-99 mmol/day) and high-dose (≥100 mmol/day)).

The investigators concluded that potassium supplementation for at least 4 weeks reduces blood pressure of patients with essential hypertension and therefore, can be recommended as an adjuvant antihypertensive agent for patients with essential hypertension (SBP ≥140 mmHg and DBP ≥90 mmHg).

Original title:
Oral potassium supplementation for management of essential hypertension: A meta-analysis of randomized controlled trials by Poorolajal J, Zeraati F, […], Maleki A.

Link:
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0174967

Additional information of El Mondo:
Find more information/studies on hypertension and potassium right here.

Objectives:
An increased intake of magnesium might lower blood pressure (BP), yet evidence from clinical trials is inconsistent, perhaps as a result of small sample size or heterogeneity in study design. Therefore, this review article (meta-analysis) has been conducted.

Are there dose-dependent effects of magnesium supplementation on blood pressure?

Study design:
This review article included 20 RCTs included 14 of hypertensive and 6 of normotensive persons totaling 1220 participants.
The doses of magnesium ranged from 10 to 40 mmol/day (median: 15.4 mmol/day or 370 mg per day).

Results and conclusions:
The investigators found magnesium supplementation resulted in only a small overall non-significant reduction in blood pressure. The pooled net estimates of blood pressure change were -0.6 mmHg [95% CI = -2.2 to 1.0] for systolic blood pressure and -0.8 mmHg [95% CI = -1.9 to 0.4] for diastolic blood pressure.

However, the investigators found an apparent dose-dependent effect of magnesium, with significant reductions of 4.3 mmHg systolic blood pressure [95% CI = 6.3 to 2.2, p 0.001) and non-significant reductions of 2.3 mmHg diastolic blood pressure [95% CI = 4.9 to 0.0, p = 0.09) for each 10 mmol/day (240 mg/day) increase in magnesium dose.

The investigators concluded there is a dose-dependent blood pressure reductions, especially systolic blood pressure from magnesium supplementation. However, adequately powered trials with sufficiently high doses of magnesium supplements need to be performed to confirm this relationship.

Original title:
The effect of magnesium supplementation on blood pressure: a meta-analysis of randomized clinical trials by Jeea SH, Miller ER, [...], Klagb MJ.

Link:
http://www.sciencedirect.com/science/article/pii/S0895706102029643

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

Objectives:
Lutein and zeaxanthin are thought to have beneficial effects on protecting the lens against cataract formation, but findings from epidemiologic studies have been inconsistent. Therefore, this review article has been conducted.

Does dietary lutein and zeaxanthin intake reduce age-related cataract risk?

Study design:
This review article included 6 prospective cohort studies, involving 4416 cases and 41999 participants.

Results and conclusions:
The investigators found for comparing the highest with the lowest categories of dietary lutein and zeaxanthin intake, a significant reduced risk for nuclear cataract of 25% [RR = 0.75, 95% CI = 0.65-0.85], but the reduced risk was not significant for cortical cataract [RR = 0.85, 95% CI = 0.53-1.17] and for posterior subcapsular cataract [RR = 0.77, 95% CI = 0.40-1.13]. Significant means, there is an association with a 95% confidence.

The investigators found in dose-response analysis that every 300 μg/d increment in dietary lutein and zeaxanthin intake was significantly associated with a 3% [RR = 0.97, 95% CI = 0.94-0.99] reduction in the risk of nuclear cataract.

The investigators found in dose-response analysis that every 300 μg/d increment in dietary lutein and zeaxanthin intake was non-significantly associated with a 1% [RR = 0.99, 95% CI = 0.95-1.02] reduction in the risk of cortical cataract. Non-significantly means, there is no association with a 95% confidence.

The investigators found in dose-response analysis that every 300 μg/d increment in dietary lutein and zeaxanthin intake was non-significantly associated with a 3% [RR = 0.97, 95% CI = 0.93-1.01] reduction in the risk of posterior subcapsular cataract. Non-significantly because RR of 1 was found in 95% CI of 0.93 to 1.01. RR of 1 means no risk.

The investigators concluded dietary lutein and zeaxanthin intake (at least 300 μg/d) is associated with a reduced risk of age-related cataract, especially nuclear cataract in a dose-response manner, indicating a beneficial effect of lutein and zeaxanthin in age-related cataract prevention.

Original title:
A dose–response meta-analysis of dietary lutein and zeaxanthin intake in relation to risk of age-related cataract by Ma L, Hao ZX, [...], Pan JP.

Link:
http://link.springer.com/article/10.1007/s00417-013-2492-3

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

Objectives:
Hormonal effects of soy and isoflavones have been investigated in numerous trials with equivocal findings. Therefore, this review article has been conducted.

What are hormonal effects of soy and isoflavones in both pre- and postmenopausal women?

Study design:
This review article included 47 (11 of pre-, 35 of post- and 1 of perimenopausal women) randomized or residential crossover trials of soy or isoflavones for 4 or more weeks on estrogens, SHBG, FSH, LH, progesterone and thyroid hormones in women was assessed independently in duplicate.

The studies ranged from 4 to 104 weeks long: 29 were 4-12 weeks in duration, 9 were 13-26 weeks, 7 were 27-52 weeks and 2 were >1 year.

Results and conclusions:
The investigators found in premenopausal women, soy or isoflavone consumption did not affect primary outcomes estradiol, estrone or SHBG concentrations, but significantly reduced secondary outcomes FSH and LH [by approximately 20% using standardized mean difference (SMD), p = 0.01 and p = 0.05, respectively].

The investigators found in 10 studies that soy or isoflavone consumption increased menstrual cycle length by 1.05 days [95% CI = 0.13-1.97].

The investigators found in post-menopausal women, soy or isoflavone consumption had no statistically significant effects on estradiol, estrone, SHBG, FSH or LH, although there was a small statistically non-significant increase in total estradiol with soy or isoflavones [by approximately 14% using standardized mean difference (SMD), p = 0.07, 21 studies].

The investigators concluded isoflavone-rich soy products decrease FSH and LH in premenopausal women and may increase estradiol in post-menopausal women. The clinical implications of these modest hormonal changes remain to be determined.

Original title:
Effects of soy protein and isoflavones on circulating hormone concentrations in pre- and post-menopausal women: a systematic review and meta-analysis by Hooper L, Ryder JJ, […], Cassidy A.

Link:
http://humupd.oxfordjournals.org/content/15/4/423.full

Additional information of El Mondo:
Find about studies/information on elderly and soy right here.

 

Objectives:
The findings of prospective cohort studies are inconsistent regarding the association between dietary magnesium intake and serum magnesium concentration and the risk of hypertension. Therefore, this review article (meta-analysis) has been conducted.

Do dietary magnesium intake and serum magnesium concentrations reduce risk of hypertension?

Study design:
This review article included 10 cohort studies, including 20,119 cases of hypertension and 180,566 participants.

The range of dietary magnesium intake was 96-25 mg/day and serum magnesium levels were 0.66-0.95 mmol/L.

The funnel plot showed reasonable symmetry, with no evidence of publication bias (Egger’s test p = 0.95 and Begg’s test p = 0.71).

Results and conclusions:
The investigators found when comparing the highest to the lowest category of dietary magnesium consumption, a significant reduced risk of 8% for hypertension [pooled RR = 0.92, 95% CI = 0.86-0.98].

The investigators found for every 100 mg/day increment in dietary magnesium intake a significant reduced risk of 5% for hypertension [pooled RR = 0.95, 95% CI = 0.90-1.00, I2 = 39.3%, p = 0.13].
The reduced hypertension risk associated with 100 mg/day was tended to be observed when the duration of follow-up was more than 8 years and when the results were adjusted separately for calcium, sodium, fiber, cholesterol, saturated fat intake or smoking.

The investigators found the dose-response meta-analysis suggested a marginal linear relationship between dietary magnesium intake and hypertension risk [p for linearity = 0.057].

The investigators found no association between serum magnesium concentrations and reduced risk of hypertension [pooled RR = 0.91, 95% CI = 0.80-1.02, p = 0.10, I2 = 0%, p = 0.48].

The investigators concluded that increased dietary magnesium intake is associated with lower risk of hypertension in a linear dose-response pattern. However, there is no association between serum magnesium concentration and risk of hypertension.

Original title:
Dose-response relationship between dietary magnesium intake, serum magnesium concentration and risk of hypertension: a systematic review and meta-analysis of prospective cohort studies by Han H, Fang X, […], Cao Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5420140/

Additional information of El Mondo:
Find more information/studies on hypertension and magnesium right here.

Objectives:
Heart failure (HF) remains a major health problem affecting 5.7 million adults in USA. Data on the association of egg consumption with incident heart failure have been inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Does egg consumption increase incident heart failure in the general population?

Study design:
This review article included 4 prospective cohort studies with a total of 105,999 subjects and 5,059 cases of new onset heart failure.

There was no evidence of publication bias on funnel plot analysis as supported by the Egger’s test (p = 0.68).

Results and conclusions:
The investigators found when comparing the highest (≥1/day) to the lowest category of egg consumption, a significant increased risk of 25% [pooled RR = 1.25, 95% CI = 1.12-1.39, p = 0.00, I2 = %] for heart failure.

The investigators found that sensitivity analysis (stratification by excluding studies with men/women, 20 years of follow-up duration, US/Non-US studies) did not alter the main conclusion.

The investigators concluded that at least 1 egg per day increases heart failure risk in the general population. Further studies are warranted to explore the underlying biological mechanisms.

Original title:
Egg Consumption and Incidence of Heart Failure: A Meta-Analysis of Prospective Cohort Studies by Khawaja O, Singh H, […], Djoussé L.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5367008/

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

Objectives:
Does a low salt intake reduce blood pressure?

Study design:
This review article included 34 randomized trials with 3230 participants (the median age was 50 (range 22-73)), of which 22 were in hypertensive individuals and 12 in normotensive individuals. Of the 34 trials, 23 used crossover design and 11 used paralleled comparisons. 22 of the 34 trials were double blind, in 11 the observer was blind to blood pressure and one did not report any blinding procedure.

The study duration varied from 4 weeks to 3 years (median 4 weeks). With the usual salt intake the median 24 hour urinary sodium was 160 mmol (range 125-200 mmol), equivalent to a salt intake of 9.4 g/day (range 7.3-11.7 g/day) and the median blood pressure was 141/86 mmHg.

Despite the fact that only 7 out of 34 trials performed intention to treat analysis, the percentage of participants lost to follow-up after randomization was small (6.7% on average).

Results and conclusions:
The investigators found meta-analysis showed that the mean change in urinary sodium (reduced salt v usual salt) was -75 mmol/24 h (equivalent to a reduction of 4.4 g/day salt), and with this reduction in salt intake, the mean change in blood pressure was -4.18 mmHg [95% CI = -5.18 to -3.18, I2 = 75%] for systolic blood pressure and -2.06 mmHg [95% CI = -2.67 to -1.45, I2 = 68%] for diastolic blood pressure.

The investigators found meta-regression showed that age, ethnic group, blood pressure status (hypertensive or normotensive) and the change in 24 hour urinary sodium were all significantly associated with the fall in systolic blood pressure, explaining 68% of the variance between studies.

The investigators found a 100 mmol reduction in 24 hour urinary sodium (equivalent to a reduction 6 g/day salt) was associated with a fall in systolic blood pressure of 5.8 mmHg [95% CI = -2.5 to -9.2,  p = 0.001] after adjustment for age, ethnic group and blood pressure status.
For diastolic blood pressure, age, ethnic group, blood pressure status and the change in 24 hour urinary sodium explained 41% of the variance between studies.

The investigators found meta-analysis by subgroup showed that in people with hypertension the mean effect was -5.39 mmHg [95% CI = -6.62 to -4.15, I2 = 61%] for systolic blood pressure and -2.82 mmHg [95% CI = -3.54 to -2.11, I2 = 52%] for diastolic blood pressure.
In normotensive people, the figures were -2.42 mmHg [95% CI = -3.56 to -1.29, I2 = 66%] and -1.00 mmHg [95% CI = -1.85 to -0.15, I2 = 66%], respectively.

The investigators found further subgroup analysis showed that the decrease in systolic blood pressure was significant in both white and black people and in men and women.

The investigators found meta-analysis of data on hormones and lipids showed that the mean change was:
0.26 ng/mL/h [95% CI = 0.17 to 0.36, I2 = 70%] for plasma renin activity;
73.20 pmol/L [95% CI = 44.92 to 101.48, I2 = 62%] for aldosterone;
187 pmol/L [95% CI = 39 to 336, I2 = 5%] for noradrenaline (norepinephrine);
37 pmol/L [95% CI = -1 to 74, I2 = 12%] for adrenaline (epinephrine);
0.05 mmol/L [95% CI = -0.02 to 0.11, I2 = 0%] for total cholesterol;
0.05 mmol/L [95% CI = -0.01 to 0.12, I2 = 0%] for low density lipoprotein cholesterol (LDL-cholesterol or bad cholesterol);
-0.02 mmol/L [95% CI = -0.06 to 0.01, I2 = 16%] high density lipoprotein cholesterol (HDL-cholesterol or good cholesterol) and:
0.04 mmol/L [95% CI = -0.02 to 0.09, I2 = 0%] for triglycerides.

The investigators concluded a modest reduction in salt intake of 4.4 g/day for 4 or more weeks causes, from a population viewpoint, important falls in blood pressure in people with both raised and normal blood pressure.
Salt reduction is associated with a small physiological increase in plasma renin activity, aldosterone and noradrenaline and no significant change in lipid concentrations.
The current recommendations to reduce salt intake from 9-12 to 5-6 g/day will have a major effect on blood pressure, but a further reduction to 3 g/day will have a greater effect and should become the long term target for population salt intake.

Original title:
Effect of longer term modest salt reduction on blood pressure: Cochrane systematic review and meta-analysis of randomised trials by He FJ, Li J and MacGregor GA.

Link:
http://www.bmj.com/content/346/bmj.f1325

Additional information of El Mondo:
Find more studies/information on sodium intake and hypertension right here.
A daily diet with a maximum of 3 grams salt per day is a diet with a maximum of 0.15 gram salt per 100 kcal.
A daily diet with a maximum of 0.15 gram salt per 100 kcal is a diet with mainly products/meals with a maximum of 0.15 gram salt per 100 kcal.

Objectives:
Approximately 5.7 million Americans carry the diagnosis of systolic heart failure (HF), a major health care burden. Heart failure is a known manifestation of thiamine deficiency (TD). Therefore, this review article has been conducted.

Is thiamine deficiency (vitamin B1 deficiency) a risk factor of systolic heart failure?

Study design:
This review article included 9 studies (observational studies and RCTs).

Results and conclusions:
The investigators found systolic heart failure patients had a higher risk of 153% of getting a thiamine deficiency [odds ratio = 2.53, 95% CI = 1.65-3.87].

The investigators found diuretic use, changes in dietary habits and altered thiamine absorption and metabolism were identified as possible mechanisms of thiamine deficiency in heart failure patients.

The investigators found small observational studies and randomized control trials suggested that thiamine supplementation in heart failure population could improve ejection fraction and reduce symptoms.

The investigators concluded thiamine deficiency is more prevalent in heart failure population, and its supplementation may be beneficial. The therapeutic role of thiamine in heart failure warrants further study.

Original title:
Determining the Role of Thiamine Deficiency in Systolic Heart Failure: A Meta-Analysis and Systematic Review by Jain A, Mehta R, […], Winchester DE.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/26497757

Additional information of El Mondo:
Find more information/studies on cardiovascular disease and vitamin B1 (thiamine) right here.