Nutrition and health

Objectives:
Women have a 50% risk of urinary tract infection (UTI) over their lifetime and 20-30% experience a subsequent urinary tract infection recurrence. Cranberry (Vaccinium spp.) has been advocated for treatment of urinary tract infection; however, its efficacy is controversial. Therefore, this review article (meta-analysis) has been conducted.

Does cranberry reduce the risk of urinary tract infection recurrence in healthy women?

Study design:
This review article included 7 RCTs conducted in healthy nonpregnant women aged ≥18 years with a history of urinary tract infection (n = 1498 participants).
Risk of bias indicated that 2 studies had high loss to follow-up or selective outcome reporting. Overall, the studies were relatively small, with only 2 having >300 participants.

Results and conclusions:
The investigators found that cranberry significantly reduced the risk of urinary tract infection by 26% [pooled risk ratio = 0.74, 95% CI = 0.55-0.98, I2 = 54%].

The investigators concluded that cranberry may be effective in preventing urinary tract infection recurrence in generally healthy women. May be effective because the studies were relatively small, with only 2 having >300 participants. Therefore, larger high-quality studies are needed to confirm these findings.

Original title:
Cranberry Reduces the Risk of Urinary Tract Infection Recurrence in Otherwise Healthy Women: A Systematic Review and Meta-Analysis by Zhuxuan Fu, DeAnn Liska, […], Mei Chung.

Link:
http://jn.nutrition.org/content/147/12/2282.abstract

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

Objectives:
Randomised controlled trials comparing low- versus high-fat diets on cardiometabolic risk factors in people with overweight or obesity have shown inconsistent results, which may be due to the mixed metabolic status of people with excess adiposity. The role of dietary fat manipulation in modifying cardiometabolic indicators in people with overweight or obese without metabolic disturbance is unclear. Therefore, this review article (meta-analysis) has been conducted.

Does a low-fat diet modify cardiometabolic indicators in people who are overweight (BMI>25) or obese (BMI>30) without metabolic disturbance?

Study design:
This review article included 20 RCTs with 2,106 participants.

Results and conclusions:
The investigators found total cholesterol levels in people who are overweight or obese without metabolic disturbance were significantly lower following low-fat diet compared with high-fat diet [WMD = -7.05 mg/dL, 95% CI = -11.30 to -2.80, p = 0.001].  

The investigators found LDL-cholesterol levels (bad cholesterol) in people who are overweight or obese without metabolic disturbance were significantly lower following low-fat diet compared with high-fat diet [WMD = -4.41 mg/dL, 95% CI = -7.81 to -1.00, p = 0.011].  

The investigators found HDL-cholesterol levels (good cholesterol) in people who are overweight or obese without metabolic disturbance were significantly lower following low-fat diet compared with high-fat diet [WMD = -2.57 mg/dL, 95% CI = -3.85 to -1.28, p 0.001].  

The investigators found TAG levels (blood fat levels) in people who are overweight or obese without metabolic disturbance were significantly higher following low-fat diet compared with high-fat diet [WMD = -11.68 mg/dL, 95% CI = 5.90 to 17.45, p 0.001].  

The investigators concluded a low-fat diet reduces cholesterol and TAG levels in people with overweight or obesity without metabolic disturbances.

Original title:
Effects of low-fat compared with high-fat diet on cardiometabolic indicators in people with overweight and obesity without overt metabolic disturbance: a systematic review and meta-analysis of randomised controlled trials by Lu M, Wan Y, [...], Li D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29212558

Additional information of El Mondo:
Find more information/studies on fat, cholesterol and overweight right here.

A triglyceride (TG, triacylglycerol, TAG or triacylglyceride) is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans.

Those with overweight or obesity are advised to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.
The most easy way to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal is to choose meals/products with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.
However, the most practical way to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal is all meals/products that you eat on a daily basis should on average contain maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.

Objectives:
Epidemiological studies have provided controversial evidence between beverage consumption and the risk of ulcerative colitis (UC). Therefore, this review article (meta-analysis) has been conducted.

Is there a relationship between beverage consumption and risk of ulcerative colitis?

Study design:
This review article included 13 case-control studies and 3 prospective cohort studies, with a total of 3,689 cases (subjects with ulcerative colitis) and 335,339 controls (subjects without ulcerative colitis).

Egger test detected no significant publication bias.

Results and conclusions:
The investigators found high intake of soft drinks versus low intake, significantly increased risk of ulcerative colitis with 69% [pooled RR = 1.69, 95% CI = 1.24-2.30, I2  =  12.9%, p  = 0 .332].
In subgroup analysis, no substantial changes of the primary result were found between subgroups.

The investigators found high tea consumption versus low consumption, significantly decreased risk of ulcerative colitis with 31% [pooled RR = 0.69, 95% CI = 0.58-0.83, I2  =  0.0%, p  = 0 .697].
In subgroup analysis, no substantial changes of the primary result were found between subgroups.

The investigators found no significant association between alcohol [pooled RR = 1.08, 95% CI = 0.66-1.51] or coffee consumption [pooled RR = 0.58, 95% CI = 0.33-1.05, I2  =  87.5%, p    0.001] and risk of ulcerative colitis. No significant association because RR of 1 was found in the 95% CI of 0.66 to 1.51. RR of 1 means no risk/association.

The investigators concluded high consumption of soft drinks increases the risk of ulcerative colitis, while high tea consumption decreases the risk.

Original title:
Beverage consumption and risk of ulcerative colitis. Systematic review and meta-analysis of epidemiological studies by Nie JY and Zhao Q.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5728934/

Additional information of El Mondo:
Find more information/studies on chronic disease, alcohol and tea consumption right here.
 

Objectives:
Dietary fiber intake may provide beneficial effects on the components of metabolic syndrome (MetS); however, observational studies reported inconsistent results for the relationship between dietary fiber intake and metabolic syndrome risk. Therefore, this review article (meta-analysis) has been conducted.

Does dietary fiber intake reduce risk of metabolic syndrome?

Study design:
This review article included 11 cross-sectional studies and 3 cohort studies.
There was evidence of publication bias in cross-sectional studies.

Results and conclusions:
The investigators found in cross-sectional studies when comparing the highest with lowest categories of dietary fiber intake, a significantly reduced risk of 33% [OR = 0.67, 95% CI = 0.58-0.78, I2 = 32.4%, p = 0.181] for metabolic syndrome. However, this reduced risk was not significant in cohort studies [pooled RR = 0.86, 95% CI = 0.70-1.06]. Not significant because RR of 1 was found in the 95% CI of 0.70 to 1.06. RR of 1 means no risk/association.

The investigators concluded that a high dietary intake of fiber may reduce risk of metabolic syndrome. May reduce because there was evidence of publication bias in cross-sectional studies and the reduced risk was not significant in cohort studies. Therefore, more prospective cohort studies are needed to further verify the association between dietary fiber intake and the risk of metabolic syndrome.

Original title:
Fruit and vegetable consumption and risk of the metabolic syndrome: a meta-analysis by Tian Y, Su L, [...], Jiang X.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29151369

Additional information of El Mondo:
Find more information/studies on publication bias/cohort studies/significant, fiber consumption and overweight right here.  

Find out whether you are overweight or not right here.

Those with metabolic syndrome are advised to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.
The most easy way to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal is to choose meals/products with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.
However, the most practical way to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal is all meals/products that you eat on a daily basis should on average contain maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.

Objectives:
Several epidemiological studies have been performed to evaluate the association of fruit and vegetable consumption with risk of the metabolic syndrome (MetS), but the results remain controversial. Therefore, this review article (meta-analysis) has been conducted.

Does consumption of vegetables or fruit reduce risk of metabolic syndrome?

Study design:
This review article included a total of 9 studies for fruit consumption, 9 studies for vegetable consumption and 7 studies for fruit and vegetable consumption.

There was no evidence of small-study effect (publication bias)

Results and conclusions:
The investigators found a significantly reduced risk of 13% [pooled RR = 0.87, 95% CI = 0.82-0.92, I2 = 46.7%] for metabolic syndrome when comparing the highest fruit consumption versus the lowest consumption.

The investigators found a significantly reduced risk of 15% [pooled RR = 0.85, 95% CI = 0.80-0.91, I2 = 0.0%] for metabolic syndrome when comparing the highest vegetable consumption versus the lowest consumption.

The investigators found a significantly reduced risk of 24% [pooled RR = 0.76, 95% CI = 0.62-0.93, I2 = 83.5%] for metabolic syndrome when comparing the highest fruit and vegetable consumption versus the lowest consumption.

The investigators found in subgroup analyses stratified by continent, the inverse association of fruit consumption [RR = 0.86, 95% CI = 0.77-0.96] and vegetable consumption [RR = 0.86, 95% CI = 0.80-0.92] with risk of metabolic syndrome remained significant in Asia.

The investigators concluded that a high fruit or/and vegetable consumption reduce risk of metabolic syndrome, particularly among Asian. Therefore, people should consume more fruits and vegetables to reduce risk of metabolic syndrome.

Original title:
Fruit and vegetable consumption and risk of the metabolic syndrome: a meta-analysis by Tian Y, Su L, [...], Jiang X.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29151369

Additional information of El Mondo:
Find more information/studies on fruit and vegetables consumption and overweight right here.  

Find out whether you are overweight or not right here.

Those with metabolic syndrome are advised to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.
The most easy way to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal is to choose meals/products with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.
However, the most practical way to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal is all meals/products that you eat on a daily basis should on average contain maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.

Objectives:
The role of omega-3 polyunsaturated fatty acids (omega-3 or n-3 PUFAs) in the pathogenesis and treatment of children and adolescents with attention deficit hyperactivity disorder (ADHD) is unclear. Therefore, this review article (meta-analysis) has been conducted.

Do children and adolescents with attention deficit hyperactivity disorder (ADHD) benefit from n-3 PUFA supplementation?

Study design:
This review article included 7 RCTs and 7 case-control studies.

Results and conclusions:
The investigators found in 7 RCTs (n = 534 randomised youth with ADHD) n-3 PUFAs supplementation significantly improved ADHD clinical symptom scores [g = 0.38, p 0.0001].

The investigators found in 3 RCTs (n = 214 randomised youth with ADHD) n-3 PUFAs supplementation significantly improved cognitive measures associated with attention [g = 1.09, p = 0.001].

The investigators found children and adolescents with ADHD had lower levels of DHA [7 case-control studies, n = 412, g = -0.76, p = 0.0002], EPA (7 case-control studies, n = 468, g = -0.38, p = 0.0008] and total n-3 PUFAs [6 case-control studies, n = 396, g = -0.58, p = 0.0001].

The investigators concluded there is evidence that n-3 PUFAs supplementation monotherapy improves clinical symptoms and cognitive performances in children and adolescents with ADHD and that these youth have a deficiency in n-3 PUFAs levels. These findings provide further support to the rationale for using n-3 PUFAs as a treatment option for ADHD.

Original title:
Omega-3 Polyunsaturated Fatty Acids in Youths with Attention Deficit Hyperactivity Disorder (ADHD): A Systematic Review and Meta-Analysis of Clinical Trials and Biological Studies by Chang JC, Su KP, [...], Pariante CM.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28741625

Additional information of El Mondo:
Find more information/studies on chronic disease, n-3 PUFA right here.
EPA and DHA are n-3 PUFA.

Objectives:
The scientific literature shows conflicting evidence about the relationship between adiposity and bone mass in overweight and obese populations. Therefore, this review article (meta-analysis) has been conducted.

Does a high adipose mass reduce bone mineral density in overweight and obese populations?

Study design:
This review article included a total of 16 studies, comprising 2587 participants and 75 correlation coefficients.

Results and conclusions:
The investigators found strong evidence supported a negative relationship between relative (%) adipose mass and bone mineral density (BMD) in men [R = -0.37, 95% CI = -0.57 to -0.12] and in those aged less than 25 years [R = -0.28, 95% CI = -0.45 to -0.08].

The investigators concluded that a high relative (%) adipose mass reduces bone mineral density in overweight (BMI = 25-30) and obese populations (BMI > 30), particularly in men and those aged less than 25 years. Therefore, to prevent bone loss in overweight and obese populations, nutrition- and exercise-based interventions that focus on a controlled reduction of adipose mass with concomitant preservation of lean mass are recommended.

Original title:
Influence of adipose tissue mass on bone mass in an overweight or obese population: systematic review and meta-analysis by Dolan E, Swinton PA, […], O'Reilly J.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29028271

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

Find out whether you are overweight or not right here.

Those with overweight (BMI = 25-30) or obesity (BMI > 30) are advised to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.
The most easy way to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal is to choose meals/products with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.
However, the most practical way to follow a diet with maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal is all meals/products that you eat on a daily basis should on average contain maximum 30 En% fat, of which maximum 7 En% saturated fat and minimum 1.5 grams fiber per 100 kcal.

Strength exercise is the best way to reduce adipose mass while preserving lean mass.

Objectives:
Recent data pose the question whether conservative management of chronic kidney disease (CKD) by means of a low-protein diet can be a safe and effective means to avoid or defer transition to dialysis therapy without causing protein-energy wasting or cachexia. Therefore, this review article (meta-analysis) has been conducted.

Do subjects with chronic kidney disease benefit from a low-protein diet?

Study design:
This review article included 16 controlled trials of low-protein diet in chronic kidney disease that met the stringent qualification criteria including having 30 or more participants.

Results and conclusions:
The investigators found compared with diets with protein intake of >0.8 g/kg/day, diets with restricted protein intake (0.8 g/kg/day) were associated with higher serum bicarbonate levels, lower phosphorus levels, lower azotemia, lower rates of progression to end-stage renal disease and a trend towards lower rates of all-cause death.

The investigators found compared with diets with protein intake of >0.8 g/kg/day, very-low-protein diets (protein intake 0.4 g/kg/day) were associated with greater preservation of kidney function and reduction in the rate of progression to end-stage renal disease.

The investigators found safety and adherence to a low-protein diet was not inferior to a normal protein diet and there was no difference in the rate of malnutrition or protein-energy wasting.

The investigators concluded a low-protein diet, particularly protein intake 0.4 g/kg/day, appears to enhance the conservative management of non-dialysis-dependent chronic kidney disease and may be considered as a potential option for chronic kidney disease patients who wish to avoid or defer dialysis initiation and to slow down the progression of chronic kidney disease, while the risk of protein-energy wasting and cachexia remains minimal.
 
Original title:
Low-protein diet for conservative management of chronic kidney disease: a systematic review and meta-analysis of controlled trials by Rhee CM, Ahmadi SF, [...], Kalantar-Zadeh K.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29094800

Additional information of El Mondo:
Find more information/studies on chronic disease and protein right here.
A protein intake of 0.8 g/kg/day usually corresponds to a diet with 11 En% protein.
A protein intake of 0.4 g/kg/day usually corresponds to a diet with 5.5 En% protein.
A diet with 5.5 En% protein is a diet with a lot of products with 5.5 En% protein. Check here which products contain 5.5 En% protein.
 

Objectives:
The prevalence of metabolic syndrome (MetS) has been greatly increased, worldwide. In recent years, investigators have proposed that sodium might contribute to the development of metabolic syndrome; however, the published data were conflicting. Therefore, this review article (meta-analysis) has been conducted.

Does sodium contribute to the development of metabolic syndrome?

Study design:
This review article included 17 observational studies with 66,274 participants.

Results and conclusions:
The investigators found that subjects with metabolic syndrome had significantly higher levels of sodium compared to healthy controls [Hedges' g = 0.21, 95% CI = 0.12-0.29, I2 = 68.6%]. Subgroup analyses revealed that the difference was significant when the sodium status was assessed using urinary sodium levels.

The investigators found that random effects meta-regression analysis also revealed that body sodium level increases with the number of metabolic syndrome components.

The investigators found that participants with highest dietary/urinary or serum sodium levels had a significantly 37% higher chance of developing metabolic syndrome when compared with participants with the lowest sodium levels [OR = 1.37, 95% CI = 1.31-1.42, I2 = 86.9%].

The investigators concluded that higher sodium input into the body is directly associated with the likelihood of metabolic syndrome. Prospective cohort studies and well-designed randomized clinical trials considering the effect of sodium restricted diets on the risk of metabolic syndrome as an outcome are necessary to represent the causal association.

Original title:
Sodium status and the metabolic syndrome: A systematic review and meta-analysis of observational studies by Soltani S, Kolahdouz Mohammadi R, […], Salehi-Abargouei A.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28846446

Additional information of El Mondo:
Find more information/studies on overweight and sodium right here. 

Find out whether you are overweight or not right here.

Those with metabolic syndrome are advised to select the following food items.

Sodium is part of table salt or sodium choride.

High-sodium or high-salt products are products with more than 0.3 gram salt per 100 kcal. These products are rich in salt.
A high-salt diet is a diet with many products with more than 0.3 gram salt per 100 kcal.

Objectives:
Over 200 clinical trials have examined the effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplements on risk factors associated with cardiovascular disease. However, an updated analysis of the evidence is lacking. Therefore, this review article (meta-analysis) has been conducted.

Do EPA and DHA supplements reduce risk of cardiovascular diseases?

Study design:
This review article included 171 RCTs with acceptable quality (Jadad score ≥3).

Results and conclusions:
The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of triglycerides of 0.368 mmol/L [95% CI = -0.427 to -0.309].
The triglyceride-lowering effect was dose-dependent.

The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of systolic blood pressure of 2.195 mmHg [95% CI = -3.172 to -1.217].

The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of diastolic blood pressure of 1.08 mmHg [95% CI = -1.716 to -0.444].

The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of heart rate of 1.37 bpm [95% CI = -2.41 to -0.325].

The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of C-reactive protein of 0.343 mg/L [95% CI = -0.454 to -0.232].

The investigators found compared to placebo-control, EPA and DHA supplements produced a significant increase of LDL cholesterol (bad cholesterol) [mean difference = 0.150 mmol/L, 95% CI = 0.058 to 0.243].

The investigators found compared to placebo-control, EPA and DHA supplements produced a significant increase of HDL cholesterol (good cholesterol) [mean difference = 0.039 mmol/L, 95% CI = 0.024-0.054].

The investigators concluded EPA and DHA supplements have lipid-lowering, hypotensive, anti-arrhythmic and anti-inflammatory effects.

Original title:
Eicosapentaenoic acid and docosahexaenoic acid containing supplements modulate risk factors for cardiovascular disease: a meta-analysis of randomised placebo-control human clinical trials by AbuMweis S, Jew S, […], Agraib L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28675488

Additional information of El Mondo:
Find more information/studies on EPA and DHA, cholesterol and cardiovascular diseases right here. 

Objectives:
The results of randomized controlled trials (RCTs) investigating resveratrol supplementation on risk factors of non-communicable diseases (NCDs) have been inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Does resveratrol supplementation reduce risk of non-communicable diseases?

Study design:
This review article included 29 RCTs (30 treatment arms) with 1069 participants.

Results and conclusions:
The investigators found that resveratrol supplementation significantly reduced the concentrations of:
-fasting glucose [-4.77 mg/dL, 95% CI = -9.33 to -0.21 mg/dL, p = 0.040];
-total cholesterol (TC) [-9.75 mg/dL, 95% CI = -17.04 to -2.46 mg/dL, p = 0.009] and;
-C-reactive protein (CRP) [-0.81 mg/L, 95% CI = -1.42 to -0.21 mg/L, p = 0.009].

The investigators found that resveratrol intervention exerted significant reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) in subjects with type 2 diabetes mellitus (T2DM).

The investigators found subgroup analysis also showed that the trials with resveratrol intervention ≥3 months significantly reduced the low-density lipoprotein (LDL) cholesterol (bad cholesterol), diastolic blood pressure and glycated hemoglobin (HbA1c) values.

The investigators found that resveratrol intervention had no favourable effects in altering high-density lipoprotein (HDL) cholesterol (good cholesterol), triglyceride (TAG) and homeostasis model assessment of insulin resistance (HOMA-IR).

The investigators concluded resveratrol supplementation ≥3 months has favourable effects on several risk factors of non-communicable diseases.

Original title:
Effects of resveratrol supplementation on risk factors of non-communicable diseases: A meta-analysis of randomized controlled trials by Guo XF, Li JM, [...], Li D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28933578

Additional information of El Mondo:
Find more information/studies on flavonoids, cholesterol, blood pressure, diabetes and chronic diseases right here.

Non-communicable or chronic diseases are diseases of long duration and generally slow progression. The four main types of non-communicable diseases are cardiovascular diseases (like heart attacks and stroke), cancer, chronic respiratory diseases (such as chronic obstructed pulmonary disease and asthma) and diabetes.

Non-communicable diseases are by far the leading cause of death in the world.
 

Objectives:
The relationships between metabolic syndrome (MetS) and risk of incident stroke are inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Does metabolic syndrome increase risk of stroke?

Study design:
This review article included a total of 16 prospective cohort studies, including 116,496 participants who were initially free of cardiovascular diseases.

Results and conclusions:
The investigators found comparing the persons without metabolic syndrome, those with metabolic syndrome had a significantly higher risk of 70% for incident stroke [pooled relative risk (RR) = 1.70, 95% CI = 1.49-1.95]. Significant means that there is an association with a 95% confidence.

The investigators found in subgroup analyses that women with metabolic syndrome had a significantly higher risk of 83% for incident stroke [pooled relative risk (RR) = 1.83, 95% CI = 1.31-2.56]. Significant because RR of 1 was not found in the 95% CI of 1.31 to 2.56. RR of 1 means no risk/association.

The investigators found in subgroup analyses that men with metabolic syndrome had a significantly higher risk of 47% for incident stroke [pooled relative risk (RR) = 1.47, 95% CI = 1.22-1.78].

The investigators found in subgroup analyses that those with metabolic syndrome had a significantly higher risk of 112% for ischemic stroke [pooled relative risk (RR) = 2.12, 95% CI = 1.46-3.08].

The investigators found in subgroup analyses that those with metabolic syndrome had a non-significantly higher risk of 48% for hemorrhagic stroke [pooled relative risk (RR) = 1.48, 95% CI = 0.98-2.24].

The investigators concluded metabolic syndrome increases risk of stroke, particularly among women and those with ischemic stroke.

Original title:
Metabolic syndrome and stroke: A meta-analysis of prospective cohort studies by Li X, Li X, […], Gao Q.

Link:
http://www.sciencedirect.com/science/article/pii/S0967586816311079

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

Find out whether you are overweight or not right here.

Those with metabolic syndrome are advised to select the following food items.

Objectives:
Promising experimental studies suggest that quercetin has potential anti-inflammatory effects. However, the results of current clinical trials on quercetin's effects on the C-reactive protein (CRP), a sensitive inflammatory biomarker, are ambiguous. Therefore, this review article (meta-analysis) has been conducted.

Does quercetin supplementation reduce CRP levels?

Study design:
This review article included 7 RCTs with 10 treatment arms.

Results and conclusions:
The investigators found a significant reduction of circulating CRP levels [WMD = -0.33 mg/L, 95% CI = -0.50 to -0.15, p 0.001] following quercetin supplementation.

The investigators found in subgroup analysis, a significant reducing effect in trials with ≥500 mg/day dosage [WMD = -0.34 mg/L, 95% CI = -0.52 to -0.16, p ≤ 0.001] and in those with CRP 3 mg/L [WMD = -0.34 mg/L, 95% CI = -0.51 to -0.18, p ≤ 0.001].

The investigators found in meta-regression, no association between changes in CRP concentrations, dose of supplementation and CRP baseline values.

The investigators concluded quercetin supplementation reduces circulating C-reactive protein levels; especially at doses above 500 mg/day and in patients with CRP 3 mg/L.
 
Original title:
Effects of supplementation with quercetin on plasma C-reactive protein concentrations: a systematic review and meta-analysis of randomized controlled trials by Mohammadi-Sartang M, Mazloom Z, […], Firoozi D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28537580

Additional information of El Mondo:
Find more information/studies on chronic disease and flavonoids right here. Quercetin is a flavonoid.

Objectives:
The associations between n-3 polyunsaturated fatty acids (PUFAs) and metabolic syndrome (MetS) risk have demonstrated inconsistent results. Therefore, this review article (meta-analysis) has been conducted.

Do higher circulating n-3 PUFA levels associate with a lower metabolic syndrome risk?

Study design:
This review article included a total of 7 case-control studies and 20 cross-sectional studies.
There was no publication bias.
Results and conclusions:
The investigators found a higher plasma/serum n-3 PUFAs was associated with a lower metabolic syndrome risk of 37% [pooled OR = 0.63, 95% CI = 0.49-0.81, I2 = 72.4%].

The investigators found the plasma/serum n-3 PUFAs in controls was significantly higher than cases [WMD = 0.24, 95% CI = 0.04-0.43], especially docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA).

The investigators found, however, no significant association between dietary intake of n-3 PUFAs or fish and metabolic syndrome risk.

The investigators found in sensitivity analysis by omitting one study at a time and re-calculated the remaining data, that exclusion of anyone study did not substantially influence the pooled effects.

The investigators concluded a higher circulating n-3 PUFAs is associated with a lower metabolic syndrome risk. The circulating n-3 PUFAs can be regarded as biomarkers indicating metabolic syndrome risk, especially DPA and DHA. The evidence of this review article will have important public implications in preventing metabolic syndrome through supplemental long-chain n-3 PUFAs of marine-origin. Furthermore, added RCTs and epidemiological studies with large sample-size are warranted to confirm these findings.

Original title:
n-3 Polyunsaturated Fatty Acids and Metabolic Syndrome Risk: A Meta-Analysis by Guo XF, Li X, […], Li D.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537818/

Additional information of El Mondo:
Find more information/studies on overweight and n-3 PUFA right here.  
Docosapentaenoic acid (DPA) is a dietary omega-3 fatty acid mainly found in fish, fish oil, seal oil and red meat.

Find out whether you are overweight or not right here.

Objectives:
Have flaxseed supplementation positive effects on body composition?

Study design:
This review article included a total of 45 RCTs.

Results and conclusions:
The investigators found a significant reduction in body weight [WMD = -0.99 kg, 95% CI = -1.67 to -0.31, p = 0.004], BMI [WMD = -0.30 kg m², 95% CI = -0.53 to -0.08, p = 0.008] and waist circumference [WMD = -0.80 cm, 95% CI = -1.40 to -0.20, p = 0.008] following flaxseed supplementation.

The investigators found subgroup analyses showed that using whole flaxseed in doses ≥30 g/d, longer-term interventions (≥12 weeks) and studies including participants with higher BMI (≥ 27 kg/m²) had positive effects on body composition.

The investigators concluded whole flaxseed supplementation in doses ≥30 g/d during ≥12 weeks has positive effects on body composition in overweight and obese participants (=participants with BMI ≥ 25 kg/m²).

Original title:
The effect of flaxseed supplementation on body weight and body composition: a systematic review and meta-analysis of 45 randomized placebo-controlled trials by Mohammadi-Sartang M, Mazloom Z, […], Totosy de Zepetnek JO.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28635182

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Objectives:
Previous studies have demonstrated that asthma might be associated with an increase in cardiovascular disease (CVD) and death. However, this relationship differs by gender. Therefore, this review article (meta-analysis) has been conducted.

Is asthma associate with an increase risk in cardiovascular disease and death among men and women?

Study design:
This review article included 4 retrospective cohort studies and 6 prospective cohort studies. The length of follow-up ranged from 4.5 to 27 years. The sample sizes of the cohorts ranged from 1,233 to 151,620 (a total of 406,426).

There was no evidence of publication bias [Begg’s, p = 1.000 and Egger’s linear regression, p = 0.150].

Results and conclusions:
The investigators found overall, subjects with asthma experienced a significant increased risk of 33% for cardiovascular disease events [RR = 1.33, 95% CI = 1.15-1.53, p 0.0001, I2 = 88%, p 0.00001]. These findings remained consistent after sensitivity analysis by omitting one study each time.

The investigators found in subgroup analyses that women with asthma had a significantly higher risk of cardiovascular disease as compared to the reference group [RR = 1.55, 95% CI = 1.20-2.00, p = 0.0007, I2 = 84%], whereas no significant association was found in men [RR = 1.20, I2 = 83%, 95% CI = 0.92-1.56, p = 0.17]. However, the combined RR value was 1.36, 95% CI = 1.15-1.62, p = 0.0003]. These findings remained consistent after sensitivity analysis by omitting one study each time.
To further explore the interaction between gender and asthma on cardiovascular disease risk, the “test for subgroup differences” were examined and gave a p = 0.17, which suggested that the influence of gender on the association between asthma and cardiovascular disease risk was not statistically significant. Therefore, it cannot confirm or refute a significant difference in the incidence of cardiovascular disease between male and female asthmatic patients.

The investigators found asthma was associated with an increased risk of 36% of all-cause mortality in a random effects model as compared to reference subjects without asthma [RR = 1.36, 95% CI = 1.01-1.83, p = 0.05, I2 = 62%, p = 0.05]. These findings remained consistent after sensitivity analysis by omitting one study each time.

The investigators concluded there is an association between asthma and an increased risk of cardiovascular disease and all-cause mortality and women with asthma have a higher risk of cardiovascular disease than men with asthma. These findings indicate a need for early detection and intervention during general outpatient visits in asthmatics who may have potential cardiovascular disease complications or mortality.

Original title:
Asthma and risk of cardiovascular disease or all-cause mortality: a meta-analysis by Xu M, Xu J and Yang X.

Link:
http://www.annsaudimed.net/index.php/vol37/vol37iss2/1109.html

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Objectives:
Iron deficiency is a prevalent nutritional disease and fatigue is a common complaint in the general and patient population, however, the association between iron deficiency without anaemia (IDNA) and fatigue is unclear. Therefore, this review article (meta-analysis) has been conducted.

Does improving iron status decrease fatigue in patients with iron deficiency without anaemia?

Study design:
This review article included a total of 6 RCTs and 6 cross-sectional studies.

Results and conclusions:
The investigators found in the meta-analysis of 6 RCTs, a significant therapeutic effect of iron supplements in fatigue patients with iron deficiency without anaemia [pooled effect size = 0.33, 95% CI = 0.17 to 0.48, I2 = 0.0%, p 0.0001]. A sensitivity analysis found that the overall results (i.e. significant association) were robust.

The investigators found in the meta-analysis of 6 cross-sectional studies, a non-significant therapeutic effect of iron supplements in fatigue patients with iron deficiency without anaemia [pooled effect size = 0.10, 95% CI = -0.11 to 0.31, I2 = 57.4%, p = 0.362]. A sensitivity analysis found that the overall results (i.e. no significant association) were not robust, however, removal of one study made the outcomes significant.

The investigators concluded improving iron status decreases fatigue in patients with iron deficiency without anaemia. However, further research is necessary to identify diagnostic criteria for selecting fatigue patients who might benefit from iron therapy and to assess the prevalence of patients with iron deficiency without anaemia in the general population.

Original title:
Iron deficiency without anaemia is a potential cause of fatigue: meta-analyses of randomised controlled trials and cross-sectional studies by Yokoi K and Konomi A.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28625177

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Objectives:
Have flaxseed supplementation positive effects on body composition?

Study design:
This review article included a total of 45 RCTs.

Results and conclusions:
The investigators found a significant reduction in body weight [WMD = -0.99 kg, 95% CI = -1.67 to -0.31, p = 0.004], BMI [WMD = -0.30 kg m², 95% CI = -0.53 to -0.08, p = 0.008] and waist circumference [WMD = -0.80 cm, 95% CI = -1.40 to -0.20, p = 0.008] following flaxseed supplementation.

The investigators found subgroup analyses showed that using whole flaxseed in doses ≥30 g/d, longer-term interventions (≥12 weeks) and studies including participants with higher BMI (≥ 27 kg/m²) had positive effects on body composition.

The investigators concluded whole flaxseed supplementation in doses ≥30 g/d during ≥12 weeks has positive effects on body composition in overweight and obese participants (=participants with BMI ≥ 25 kg/m²).

Original title:
The effect of flaxseed supplementation on body weight and body composition: a systematic review and meta-analysis of 45 randomized placebo-controlled trials by Mohammadi-Sartang M, Mazloom Z, […], Totosy de Zepetnek JO.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28635182

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Objectives:
Dietary intake is potentially associated with the onset of Crohn’s disease (CD), but evidence from epidemiological studies has remained unclear. Therefore, this review article (meta-analysis) has been conducted.

Is there a positive association between fat, carbohydrate or protein intake and the risk of Crohn’s disease?

Study design:
This review article included 4 case-control studies with a total of 311 Crohn’s disease cases and 660 controls and 5 prospective cohort studies with a total of 238,887 participants and 482 Crohn’s disease cases.

The Egger’s test detected no obvious publication bias in fiber (p = 0.708), while there were not enough studies to conduct the analyses for carbohydrate, fat and protein.

Results and conclusions:
The investigators found no evidence of a non-linear relationship between total carbohydrate intake and Crohn’s disease risk [p for non-linearity = 0.376].

The investigators found no association between 10 g increment/day of total carbohydrate intake and Crohn’s disease risk [RR = 0.991, 95% CI = 0.978-1.004, I2 = 0.0%, p = 0.439]. No association because RR of 1 was found in the 95% CI of 0.978 to 1.004. RR of 1 means no risk/association.

The investigators found no evidence of a non-linear relationship between total fat intake and Crohn’s disease risk [p for non-linearity = 0.281].

The investigators found no association between 10 g increment/day of total fat intake and Crohn’s disease risk [RR = 1.018, 95% CI = 0.969-1.069, I2 = 44.6%, p = 0.125].

The investigators found no evidence of a non-linear relationship between total protein intake and Crohn’s disease risk [p for non-linearity = 0.163].

The investigators found no association between 10 g increment/day of total protein intake and Crohn’s disease risk [RR = 1.029, 95% CI = 0.955-1.109, I2 = 54.7%, p = 0.085].

The investigators found a non-linear relationship between fiber dietary intake and Crohn’s disease risk [p for non-linearity = 0.019].

The investigators found a significant reduced risk of 14.7% for Crohn’s disease for per 10 g increment/day of fiber [RR = 0.853, 95% CI = 0.762-0.955]. However, the protective role of fiber dietary intake in the development of Crohn’s disease was gone after adjustment for the risk factor smoking [RR for per 10 g increment/day = 0.890, 95% CI = 0.776-1.020].

The investigators found a non-linear relationship between sucrose intake and Crohn’s disease risk [p for non-linearity = 0.023].

The investigators found a significant increased risk of 8.8% for Crohn’s disease for per 10 g increment/day of sucrose [RR = 1.088, 95% CI = 1.020-1.160, I2 = 0.0%, p = 0.39]. Significant means it can be said with a 95% confidence that each 10 g increment/day of sucrose really increased the risk of Crohn’s disease. 

The investigators concluded there is a lack of association between total carbohydrate, fat or protein intake and the risk of Crohn’s disease, while high fiber dietary intake might decrease the risk but the association was influenced by study design and smoking adjustment. High sucrose intake might increase the risk of Crohn’s disease. However, large-scale prospective designed studies are needed to confirm these findings.

Original title:
Macronutrient Intake and Risk of Crohn’s Disease: Systematic Review and Dose–Response Meta-Analysis of Epidemiological Studies by Zeng L, Hu S, [...], Tan Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452230/

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Find more information/studies on fat, protein, carbohydrate and fiber right here.

 

Objectives:
Do overweight and obese adults benefit from n-3 PUFA supplements?

Study design:
This review article included a total of 11 RCTs involving 617 participants.

Results and conclusions:
The investigators found a statistically non-significant difference in weight loss between n-3 PUFA supplements and placebo [WMD = 0.00, 95% CI = -0.42 to 0.43, p = 0.99].

The investigators found n-3 PUFA supplements was superior to placebo in reducing serum triglyceride levels [Std MD = -0.59, 95% CI = -0.93 to -0.25, p = 0.0007].

The investigators found a significant reduction in waist circumference for n-3 PUFA group [WMD = -0.53, 95% CI = -0.90 to -0.16, p = 0.005].

The investigators found no significant differences in body mass index, total serum levels of cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol and fasting glucose levels between n-3 PUFA supplements and placebo.

The investigators concluded that n-3 PUFA supplements reduce waist circumference and triglyceride levels in overweight and obese adults. However, large-scale, well-designed RCTs are needed to further address this issue.

Original title:
Efficacy of Omega-3 Polyunsaturated Fatty Acids Supplementation in Managing Overweight and Obesity: A Meta-Analysis of Randomized Clinical Trials by Zhang YY, Liu W, […], Tian HM.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28112774

Additional information of El Mondo:
Find more information/studies on overweight, n-3 PUFA and cholesterol right here.  

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Objectives:
The effects of green tea on lipid metabolism were inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Have tea consumption beneficial effects on lipid metabolism?

Study design:
This review article included 21 RCTs studying 1,704 overweight or obese subjects.

Results and conclusions:
The investigators found that green tea consumption significantly decreased plasma total cholesterol with 3.38 mg/dL [WMD = -3.38 mg/dL, 95% CI = -6.42 to -0.33 mg/dL] in overweight or obese people.

The investigators found that green tea consumption significantly decreased plasma LDL cholesterol (bad cholesterol) with 5.29 mg/dL [WMD = -5.29 mg/dL,95% CI = -7.92 to -2.66 mg/dL] in overweight or obese people.

The investigators found that green tea consumption, however, showed no effect on plasma triglyceride and HDL cholesterol levels (good cholesterol) in overweight or obese people with a relatively high heterogeneity.

The investigators concluded that drinking green tea lowers plasma total cholesterol and LDL cholesterol levels in overweight or obese people. Nevertheless, green tea's effect on plasma triglyceride and HDL cholesterol levels must be further evaluated by additional high-quality and large-scale RCTs.

Original title:
Effects of green tea on lipid metabolism in overweight or obese people: A meta-analysis of randomized controlled trials by Fen Y, Hui D, [...], Fu Er L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28636182

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Objectives:
C-reactive protein (CRP) has been proposed as a risk marker and risk factor of cardiovascular disease. There have been a number of clinical reports suggesting that supplementation with L-carnitine can modulate systemic inflammation and lower circulating CRP concentrations, but the results have not been consistent. Therefore, this review article (meta-analysis) has been conducted.

Does supplementation with L-carnitine reduce circulating CRP concentrations?

Study design:
This review article included 6 RCTs comprising 541 cases and 546 controls.
3 studies were conducted in diabetic or prediabetic patients, 2 studies in hemodialysis patients and 1 study in patients with non-alcoholic steatohepatitis.
Duration of L-carnitine supplementation ranged between 8 to 48 weeks.
Dosage of L-carnitine ranged between 1-2 g/day in all the included trials.

Results and conclusions:
The investigators found in random effect analysis a statistically significant pooled effect size [net change = -0.39 mg/L, 95% CI = -0.62 to -0.16, p = 0.001, I2 = 44%, p = 0.11] for the impact of L-carnitine supplementation among 541 cases and 546 controls. This effect size estimate was found to be robust and remained unaffected by the removal of each single study.

The investigators concluded the present meta-analysis support the clinically relevant benefit of L-carnitine supplementation (1-2 g/day) in lowering the circulating levels of CRP. Conducting future, large-scale, randomized clinical trials is warranted in homogenous populations to verify the findings of this meta-analysis.

Original title:
Effect of L-carnitine Supplementation on Circulating C-reactive Protein Levels: A Systematic Review and Meta-Analysis by Sahebkar A.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4922328/

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Higher circulating levels of CRP increase inflammation.
 

Objectives:
Is there a causal association between low serum vitamin D concentrations, increased body mass index (BMI) and pediatric-onset multiple sclerosis (MS) using genetic risk scores (GRS)?

Study design:
This review article included participants of non-Hispanic white individuals recruited from over 15 sites across the United States (n = 394 cases, 10,875 controls) and Sweden (n = 175 cases, 5,376 controls; total n = 16,820).

Results and conclusions:
The investigators found meta-analysis findings demonstrated that a vitamin D GRS associated with increasing levels of 25(OH)D in serum significantly decreased risk of pediatric-onset MS with 28% [OR =  0.72, 95% CI = 0.55-0.94, p = 0.02] after controlling for sex, genetic ancestry, HLA-DRB1*15:01 and over 100 non-human leukocyte antigen MS risk variants.

The investigators also found that a higher BMI GRS significant increased risk of pediatric-onset MS with 17% [OR = 1.17, 95% CI = 1.05-1.30, p = 0.01] after adjusting for covariates.

The investigators found estimates for each GRS were unchanged when considered together in a multivariable model.

The investigators concluded evidence supporting independent and causal effects of decreased vitamin D levels and increased BMI on susceptibility to pediatric-onset MS.

Original title:
Evidence for a causal relationship between low vitamin D, high BMI, and pediatric-onset MS by Gianfrancesco MA, Stridh P, […], Waubant E.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28356466

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Objectives:
Epidemiological studies have presented inconsistent evidence of the correlation between a fish-oriented dietary intake (FDI) and the risk of cognitive decline. Therefore, this meta-analysis (review article) has been conducted.

Does a fish-oriented dietary intake reduce risk of cognitive decline?

Study design:
This review article included 9 cohort studies containing 28,754 subjects.
Limited evidence involving heterogeneity was found within subgroups or across studies.

Results and conclusions:
The investigators found when comparing the highest versus lowest categories of fish consumption a significant reduced risk of 20% [RR = 0.80, 95% CI = 0.65-0.97] for dementia of Alzheimer type (DAT).

The investigators found the dose-response synthesized data indicated that a 100-g/week increase in fish intake reduced the risk of dementia of Alzheimer type by an additional 12% [RR = 0.88, 95% CI = 0.79-0.99].

The investigators found that the reduced risk of dementia of all causes (DAC) and mild cognitive impairment (MCI) was non-significant.

The investigators concluded that a higher intake of fish, at least 100-g/week is correlated with a reduced risk of dementia of Alzheimer type.

Original title:
An exploration of the role of a fish-oriented diet in cognitive decline: a systematic review of the literature by Zeng LF, Cao Y, […], Wang NS.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28418899

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Objectives:
Recent studies have found that the serum zinc levels were associated with the risk of Parkinson's disease (PD), but the results were inconsistent. Therefore, this meta-analysis (review article) has been conducted.

Is there an association between serum zinc levels and Parkinson's disease risk?

Study design:
This review article included 11 articles involving 822 Parkinson's disease patients and 777 healthy controls (subjects without Parkinson's disease).

No publication bias was found.

Results and conclusions:
The investigators found that the serum zinc levels in Parkinson's disease patients were significantly lower than those in health controls [SMD = -0.779, 95% CI = -1.323 to -0.234, p 0.001].

This association was also significant in oriental studies [SMD = -1.601, 95% CI = -2.398 to -0.805, p 0.001].

The investigators concluded that serum zinc levels in Parkinson's disease patients are significantly lower than those in healthy controls.

Original title:
Association Between Serum Zinc Levels and the Risk of Parkinson's Disease: a Meta-Analysis by Sun H, Liu X, […], Li W.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28160244

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