Nutritional advice

Objectives:
Do diets rich in protein causually reduce body weight of adults with overweight or obesity? 

Study design:
This review article included 37 RCTs.
The diets were included during a mean of 32 weeks interventions, ranging from 8 to 104 weeks.

There was no publication bias.

Results and conclusions:
The investigators found protein intake (ranging from 18-59 energy percentage [En%]) significantly reduced body weight by 1.6 kg [95% CI = 1.2 to 2.0 kg, I2 = 56%] compared to controls (digestible carbohydrate, fiber, fat or no supplementation (no placebo used)).
This result was also found in sensitivity analysis.

The investigators found the effect size of dietary protein in body weight management was dependent on specific phenotypes, where individuals with prediabetes had more benefit compared to individuals with normoglycemia.
Furthermore, individuals without the obesity risk allele (AA genotype) had more benefit compared to individuals with the obesity risk alleles (AG and GG genotypes).

The investigators concluded that diets rich in protein (18-59 energy percentage [En%]) during 32 weeks causally have a moderate beneficial effect on body weight management of adults with overweight or obesity.

Original title:
Are Dietary Proteins the Key to Successful Body Weight Management? A Systematic Review and Meta-Analysis of Studies Assessing Body Weight Outcomes after Interventions with Increased Dietary Protein by Hansen TT, Astrup A and Sjödin A.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8468854/

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

A diet rich in protein with 18-59 energy percentage [E%] or a diet with 18-59 En% protein means that the amounts of protein contribute 18 to 59% to the total calories (kcal) of the diet.
If the diet contains 2000 kcal, 90 grams of protein contribute 18% to this 2000 kcal.
1 gram of protein gives 4 kcal. Thus 90 grams of protein provide 360 kcal (90x4 kcal) and 360 kcal is 18% of 2000 kcal.

The most easy way to follow a diet rich in protein with 18-59 energy percentage is to choose only meals/products with 18-59 En% protein. Check here which products contain 18-59 En% protein.

However, the most practical way to follow a diet with 18-59 En% protein is, all meals/products that you eat on a daily basis should contain on average 18-59 En% protein.

To do this, use the 7-points nutritional profile app to see whether your daily diet contains 18-59 En% protein.

A high-protein diet is a diet with at least 20 En% protein.

 

Objectives:
The association between vitamin C and metabolic syndrome (MetS) has been evaluated in several epidemiological studies with conflicting results. Therefore, this review article has been conducted.

Do dietary vitamin C intake and circulating vitamin C level reduce risk of metabolic syndrome? 

Study design:
This review article included 26 cross-sectional studies and 2 cohort studies with a total number of 110,771 participants. 23 studies were related to the dietary vitamin C level.
The sample size ranged from 143 to 27,656 persons.
The dietary vitamin C level was assessed by food-frequency questionnaire (FFQ) in 4 studies, a 24-h or 3-day recall in 18 studies and a 4-day record in 1 study.

No evidence of publication bias existed according to Begg's rank correlation test [p = 0.495].

Results and conclusions:
The investigators found when compared to the lowest dietary vitamin C intake, that the highest dietary vitamin C intake significantly reduced risk of metabolic syndrome with 7% [overall multivariable-adjusted RR = 0.93, 95% CI = 0.88 to 0.97, p = 0.003, I2 = 54.5%, p = 0.003]. The above findings were confirmed in cross-sectional studies [RR = 0.92, 95% CI = 0.87 to 0.97, p = 0.001] and 24-h or 3-day recall [RR = 0.89, 95% CI = 0.86 to 0.93, p 0.001] studies.

The investigators found when compared to the lowest circulating vitamin C level, that the highest circulating vitamin C level significantly reduced risk of metabolic syndrome with 40% [overall multivariable-adjusted RR = 0.60, 95% CI = 0.49 to 0.74, p 0.001, I2 = 22.7%, p = 0.249].

The investigators concluded that both the dietary and the circulating vitamin C level reduce risk of metabolic syndrome. However, due to the limitation of the available evidence, more well-designed prospective studies are still needed.

Original title:
Vitamin C and Metabolic Syndrome: A Meta-Analysis of Observational Studies by Guo H, Ding J, [...], Zhang Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8531097/

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

In practice, a lot of dietary vitamin C intake amounts to 200 to 300 grams of vegetables and 2-5 pieces of fruit per day. Vitamin C is found in fruit and vegetables.

A high circulating vitamin C level can be obtained through vitamin C-rich food and/or taking vitamin C supplements.

 

Objectives:
The associations between dietary carbohydrate and diverse health outcomes remain controversial and confusing. Therefore, this review article (meta-analyse) has been conducted.

What is the association between dietary carbohydrate intake and diverse health outcomes?

Study design:
This review article included 43 meta-analyses of observational research studies with 23 health outcomes, including cancer (n = 26), mortality (n = 4), metabolic diseases (n = 4), digestive system outcomes (n = 3) and other outcomes [coronary heart disease (n = 2), stroke (n = 1), Parkinson's disease (n = 1) and bone fracture (n = 2)].

This umbrella review summarized 281 individual studies with 13,164,365 participants.

33.3% studies were considered to be of high quality and 66.7% of moderate quality.

Results and conclusions:
The investigators found highly suggestive evidence showed that dietary carbohydrate intake significantly increased risk of metabolic syndrome with 25% [adjusted summary odds ratio = 1.25, 95% CI = 1.15 to 1.37].

The investigators found suggestive evidence showed that dietary carbohydrate intake significantly decreased risk of esophageal adenocarcinoma with 43% [adjusted summary hazard ratio = 0.57, 95% CI = 0.42 to 0.78].

The investigators found suggestive evidence showed that dietary carbohydrate intake significantly increased risk of all-cause mortality with 19% [adjusted summary hazard ratio 1.19, 95% CI = 1.09 to 1.30].

The investigators concluded despite the fact that numerous systematic reviews and meta-analyses have explored the relationship between carbohydrate intake and diverse health outcomes, there is no convincing evidence of a clear role of carbohydrate intake. However, highly suggestive evidence shows carbohydrate intake is associated with higher risk of metabolic syndrome. Suggestive evidence shows carbohydrate intake is associated with higher risk of all-cause mortality and lower risk of esophageal adenocarcinoma.

Original title:
Dietary Carbohydrate and Diverse Health Outcomes: Umbrella Review of 30 Systematic Reviews and Meta-Analyses of 281 Observational Studies by Liu YS, Wu QJ […], Zhao YH.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8116488/

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

Objectives:
What is the association between red meat and poultry consumption and the risk of metabolic syndrome?

Study design:
This review article included 9 prospective cohort studies, which involved a total of 21,869 participants.
Among them, 8 studies were identified for red meat consumption.

No publication bias was observed according to the Begg's rank-correlation test and the Egger's test.  

Results and conclusions:
The investigators found that red meat consumption was significantly associated with a higher risk of 35% for metabolic syndrome [multi-variable adjusted RR = 1.35, 95% CI = 1.13 to 1.62, p = 0.001, I2 = 54.4%, p = 0.032].  
The same results were obtained in subgroup analysis for >5 years follow-up [RR = 1.36, 95% CI = 1.09 to 1.7, p = 0.006], non-National Cholesterol Education Program-Adult Treatment Panel (NCEP-ATP III) [RR = 1.34, 95% CI = 1.12 to 1.62, p = 0.002], Non-Asia [RR = 1.51, 95% CI = 1.29 to 1.77, p 0.001], adjustment of BMI [RR = 1.4, 95% CI = 1.23 to 1.6, p 0.001] and physical activity studies [RR = 1.48, 95% CI = 1.29 to 1.71, p 0.001].

The investigators found that unprocessed red meat consumption was significantly associated with a higher risk of 32% for metabolic syndrome [multi-variable adjusted RR = 1.32, 95% CI = 1.14 to 1.54, p = 0.0003, I2 = 0%, p = 0.397].  

The investigators found that processed red meat consumption was significantly associated with a higher risk of 48% for metabolic syndrome [multi-variable adjusted RR = 1.48, 95% CI = 1.11 to 1.97, p = 0.007, I2 = 64.7%, p = 0.097].  

The investigators found that poultry consumption was significantly associated with a lower risk of 15% for metabolic syndrome [multi-variable adjusted RR = 0.85, 95% CI = 0.75 to 0.97, p = 0.02, I2 = 0%, p = 0.707].  

The investigators concluded that red meat (processed and unprocessed) consumption is associated with a higher risk of metabolic syndrome, whereas, poultry consumption is associated with a lower risk of metabolic syndrome. More well-designed randomized controlled trials are still needed to address the issues further.

Original title:
Association of Red Meat and Poultry Consumption With the Risk of Metabolic Syndrome: A Meta-Analysis of Prospective Cohort Studies by Guo H, Ding J, [...], Zhang Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8295459/

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

Objectives:
Nuts are recommended for cardiovascular health, yet concerns remain that nuts may contribute to weight gain due to their high energy density. Therefore, this review article has been conducted.

Does nut consumption contribute to an increased adiposity risk?

Study design:
This review article included 6 prospective cohort studies with 569,910 participants and 86 RCTs with 114 comparisons and 5,873 participants.

Results and conclusions:
The investigators found nuts consumption was significantly associated with a lower risk of 7% for incidence of overweight/obesity [RR = 0.93, 95% CI = 0.88 to 0.98, p 0.001, moderate certainty of evidence] in prospective cohort studies.

The investigators found RCTs showed no adverse effect of nuts on body weight [MD = 0.09 kg, 95% CI = -0.09 to 0.27 kg, p 0.001, high certainty of evidence].

The investigators found meta-regression showed that higher nut intake was significantly associated with reductions in body weight and body fat.

The investigators concluded that current evidence demonstrates the concern that nut consumption contributes to increased adiposity appears unwarranted.

Original title:
Are fatty nuts a weighty concern? A systematic review and meta-analysis and dose-response meta-regression of prospective cohorts and randomized controlled trials by Nishi SK, Viguiliouk E, [...], Sievenpiper JL.

Link:
https://pubmed.ncbi.nlm.nih.gov/34494363/

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

Objectives:
Diets with high glycemic index (GI) or high glycemic load (GL) have been linked to important risk factors associated with the development of metabolic syndrome (MetS), such as dyslipidemia, higher blood glucose and insulin concentrations. However, the role of GI and GL in relation to metabolic syndrome is still understudied and controversial. Therefore, this review article has been conducted.

Does high dietary GI or GL increase risk of metabolic syndrome?

Study design:
This review article included 1 cohort study and 11 cross-sectional studies with a total sample size of 36,295 subjects.

Results and conclusions:
The investigators found, the pooled effect sizes from the 9 studies indicated high versus low dietary GI was significantly associated with increased risk of 5% for metabolic syndrome [OR = 1.05, 95% CI = 1.01 to 1.09, I2 = 58.1%, p = 0.004].
This finding was supported by all subgroup analyses except where studies used 24-h recalls for dietary assessment.

The investigators found, additionally, a linear dose-response investigation revealed that each 5-point increment in GI was associated with 2% increase in the risk of metabolic syndrome [OR = 1.02, 95% CI = 1.01 to 1.02].
Howver, non-linear pattern was insignificant [p-nonlinearity = 0.63].

The investigators found, moreover, pooled effect sizes from 10 studies suggested that no association was found between the GL and metabolic syndrome with results remaining consistent in all subgroup analyses.

The investigators concluded that high dietary GI increases risk of metabolic syndrome. Nutrition policy and clinical practices should encourage a diet with low GI. Future studies should include both GI and GL and different criteria of metabolic syndrome to provide a better comparison.

Original title:
Glycemic index, but not glycemic load, is associated with an increased risk of metabolic syndrome: Meta-analysis of observational studies by Askari M, Dehghani A, […], Alizadeh S.

Link:
https://pubmed.ncbi.nlm.nih.gov/33928722/

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

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

Objectives:
Excess body weight, including overweight and obesity, is one of the major factors influencing human health and plays an important role in the global burden of disease. Carotenoids serve as precursors of vitamin A-related retinoids and are considered to have potential effects on many diseases. However, the influence of carotenoids on people with excess body weight is unclear. Therefore, this review article has been conducted.

Does carotenoid supplementation reduce risk of overweight and obesity in overweight or obese subjects?

Study design:
This review article included 7 randomized controlled trials (RCTs) and 8 observational studies with 28,944 subjects and data on multiple carotenoid subgroups, including lycopene, astaxanthin, cryptoxanthin, α-carotene, and β-carotene.

In all included RCTs, the intervention duration was 20 days at the shortest and 16 weeks at the longest and the range of intervention doses was 1.2-60 mg/d.

Results and conclusions:
The investigators found that the insufficiency of serum carotenoids significantly increased risk of overweight and obesity with 73% [OR = 1.73, 95% CI = 1.57 to 1.91, p 0.001].

The investigators found, moreover, carotenoid supplementation was significantly associated with body weight reductions [SMD = -2.34 kg, 95% CI = -3.80 to -0.87 kg, p 0.001], body mass index decrease [SMD = -0.95 kg/cm², 95% CI = -1.88 to -0.01 kg/cm², p 0.001] and waist circumference losses [SMD = -1.84 cm, 95% CI = -3.14 to -0.54 cm, p 0.001].

The investigators concluded that 1.2-60 mg/d carotenoid supplementation reduces risk of overweight and obesity in overweight or obese subjects. Furthermore, an insufficiency of serum carotenoids is a risk factor for overweight and obesity. Additional data from large clinical trials are needed.

Original title:
The association between carotenoids and subjects with overweight or obesity: a systematic review and meta-analysis by Yao N, Yan S, […], Cui W.

Link:
https://pubmed.ncbi.nlm.nih.gov/33977977/

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

Am I overweight?
 

Objectives:
The evidence on the association between obesity and atrial fibrillation (AF) recurrence was equivocal. Therefore, this review article (meta-analysis) has been conducted.

Does obesity increase risk of atrial fibrillation recurrence in patients undergoing catheter ablation?

Study design:
This review article included 20 studies with 52,771 patients.

Results and conclusions:
The investigators found that obesity was significantly associated with higher atrial fibrillation recurrence [OR = 1.30, 95% C = 1.16 to 1.47, p 0.001, I2 = 72.7%] and similar rate of adverse events [OR = 1.21, 95% CI = 0.87 to 1.67, p = 0.264, I2 = 23.9%] in patients undergoing catheter ablation.

The investigators found meta-regression showed that the association varied by age [coefficient = -0.03, p = 0.024].

The investigators found meta-analysis of highest versus lowest BMI showed that the highest group had higher atrial fibrillation recurrence [OR = 1.37, 95% CI = 1.18 to 1.58, p 0.001, I2 = 64.9%] and adverse events [OR = 2.02, 95% CI = 1.08 to 3.76, p = 0.028, I2 = 49.5%] in patients undergoing catheter ablation.

The investigators found the dose-response relationship for BMI and atrial fibrillation recurrence was nonlinear [p nonlinearity 0.001], the curve became steeper at 30-35 kg/m².

The investigators found for adverse events, an increase of 1% for every 1 kg/m² increase in BMI [OR = 1.01, 95% CI = 1.00 to 1.02, p = 0.001], the relationship was nonlinear [p nonlinearity = 0.001].

The investigators concluded that obesity is associated with higher atrial fibrillation recurrence in patients undergoing catheter ablation. High BMI is associated with a higher risk for adverse events.

Original title:
BMI and atrial fibrillation recurrence post catheter ablation: A dose-response meta-analysis by Pranata R, Henrina J, […], Munawar M.

Link:
https://pubmed.ncbi.nlm.nih.gov/33544873/

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

Catheter ablation is a procedure that uses radiofrequency energy (similar to microwave heat) to destroy a small area of heart tissue that is causing rapid and irregular heartbeats. Destroying this tissue helps restore your heart’s regular rhythm. Catheter ablation is also called radiofrequency ablation.

Am I overweight?
 

Objectives:
A few randomized controlled trials (RCTs) have assessed the effect of brown rice consumption on metabolic parameters (such as, weight, height, waist circumference, fasting glucose, LDL, HDL, total cholesterol, triglycerides and blood pressure) compared to white rice, with inconsistent findings. Therefore, this review article has been conducted.

Is the effect of brown rice on adiposity indices (such as, weight, height and waist circumference), lipid profile (such as, LDL, HDL, total cholesterol and triglycerides) and glycemic markers (such as, fasting blood glucose) higher compared to white rice in adult subjects?

Study design:
This review article included 13 RCTs.
In accordance with Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, the certainly of the included evidence was low and very low.

Results and conclusions:
The investigators found brown rice significantly reduced:
weight by -1.63 kg [95% CI = -2.15 to -1.11, I2 = 97%, n = 6];
body mass index (BMI) by -0.58 kg/m² [95% CI = -0.78 to -0.37, I2 = 96%, n = 6] and;
waist circumference by -2.56 cm [95% CI = -4.86 to -0.26, I2 = 88%, n = 5] compared with white rice.

The investigators found, moreover, brown rice had no significant effect on lipid profile and glycemic markers.

The investigators found pre-germinated brown rice significantly declined:
weight by -1.75 kg [95% CI = -2.70 to -0.81, I2 = 99%, n = 4];
total cholesterol by -24.22 mg/dL [95% CI = -33.03 to -15.41, I2 = 78%, n = 5];
triglyceride (TG) by -43.28 mg/dL [95% CI = -74.05 to -12.50, I2 = 90%, n = 5];
low-density lipoprotein (LDL or bad cholesterol) by -20.05 mg/dL [95% CI = -29.57 to -10.52, I2 = 71%, n = 5] and;
fasting blood glucose (FBG) by -15.83 mg/dL [95% CI = -25.20 to -6.46, I2 = 91%, n = 5] compared to white rice.

The investigators concluded brown rice has anti-obesity effects in comparison with white rice. However, it has no beneficial effects on lipid profile and glycemic markers. Furthermore, pre-germinated brown rice has better functional effects on promoting lipid profile and fasting blood glucose compared to brown rice.

Original title:
The effect of brown rice compared to white rice on adiposity indices, lipid profile, and glycemic markers: a systematic review and meta-analysis of randomized controlled trials by Golzarand M, Toolabi K, […], Mirmiran P.

Link:
https://pubmed.ncbi.nlm.nih.gov/33905269

Additional information of El Mondo:
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Objectives:
Several mechanisms have been proposed for the effect of vitamin E on weight loss. Yet various interventional studies with wide ranges of doses and durations have reported contradictory results. Therefore, this review article has been conducted.

Does vitamin E supplementation reduce overweight?

Study design:
This review article included 24 RCTs.

Results and conclusions:
The investigators found there was no significant effect of vitamin E supplements on weight [WMD = 0.15, 95% CI = -1.35 to 1.65, p = 0.847], body mass index (BMI) [WMD = 0.04, 95% CI = -0.29 to 0.37, p = 0.815] and waist circumference (WC) [WMD = -0.19 kg, 95% CI = -2.06 to 1.68, p = 0.842], respectively.

The investigators found, however, subgroup analysis revealed that vitamin E supplementation in studies conducted on participants with normal BMI (18.5-24.9) had increasing impact on BMI [p = 0.047].  

The investigators concluded there is no significant effect of vitamin E supplementation on weight, BMI and waist circumference (WC). However, vitamin E supplementation increases BMI in participants with normal BMI (18.5-24.9).

Original title:
Can vitamin E supplementation affect obesity indices? A systematic review and meta-analysis of twenty-four randomized controlled trials by Emami MR, Jamshidi S, […], Aryaeian N.

Link:
https://pubmed.ncbi.nlm.nih.gov/33632535/

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

Objectives:
Recent systematic reviews and meta-analyses of randomized, double-blind, placebo-controlled trials (double-blind, placebo-controlled RCTs) have reported controversial findings regarding the associations between calcium supplements on the risk of cardiovascular disease (CVD). Therefore, this review article has been conducted.

Do calcium supplements increase risk of cardiovascular disease (CVD)?

Study design:
This review article included 13 RCTs with 28,935 participants in an intervention group (group with calcium supplements) and 14,243 in a control group (group without calcium supplements).

The mean age of the study participants was 66.3 years (range: 35 to 97 years) and 92.8% of those were women.
Publication bias was not observed.

Results and conclusions:
The investigators found calcium supplements significantly increased the risk of cardiovascular disease with 15% in healthy postmenopausal women [RR = 1.15, 95% CI = 1.06 to 1.25, I2 = 0.0%, n = 14].

The investigators found calcium supplements significantly increased the risk of coronary heart disease with 16% in healthy postmenopausal women [RR = 1.16, 95% CI = 1.05 to 1.28, I2 = 0.0%, n = 9].

The investigators found in the subgroup meta-analysis, dietary calcium intake of 700-1000 mg per day or supplementary calcium intake of 1000 mg per day significantly increased the risk of cardiovascular disease and coronary heart disease.

The investigators concluded that the use of calcium supplements (1000 mg per day) is significantly associated with the increased risk of cardiovascular disease and coronary heart disease by 15%, specifically in postmenopausal women. These findings should be explicitly confirmed by conducting further RCTs with cardiovascular disease outcome measures as well as the incidence of osteoporosis or fractures as the primary endpoints.

Original title:
Calcium Supplements and Risk of Cardiovascular Disease: A Meta-Analysis of Clinical Trials by Myung SK, Kim HB, […], Oh SW.

Link:
https://pubmed.ncbi.nlm.nih.gov/33530332/

Additional information of El Mondo:
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Objectives:
Vitamin D deficiency during pregnancy or infancy is associated with adverse growth in children. No systematic review has been conducted to summarize available evidence on the effect of vitamin D supplementation in pregnancy and infancy on growth and body composition in children. Therefore, this review article has been conducted.

Does vitamin D supplementation during pregnancy or infancy increase adiposity (severe or morbid overweight) risk in childhood?

Study design:
This review article included 12 RCTs with a total of 4,583 participants.
The doses of vitamin D in the intervention group (group with vitamin D supplements) were 60,000 IU/4 weeks (1,500 mcg/4 weeks) or 60,000 IU/8 weeks and in the control group (group without vitamin D supplements) was 400 IU/day.

Results and conclusions:
The investigators found vitamin D supplementation during pregnancy was associated with higher triceps skinfold thickness (mm) [MD = 0.33, 95% CI = 0.12 to 0.54, I2 = 34%] in neonates.

The investigators found vitamin D supplementation during pregnancy or infancy was associated with significantly increased length for age z-score in infants at 1 year of age [MD = 0.29, 95% CI = 0.03 to 0.54, I2 = 0%].

The investigators found vitamin D supplementation during pregnancy or infancy was associated with lower body mass index (BMI) (kg/m²) [MD = -0.19, 95% CI = -0.34 to -0.04, I2 = 0%] and body mass index z-score (BMIZ) [MD = -0.12, 95% CI = -0.21 to -0.04, I2 = 0%] in offspring at 3-6 years of age.

The investigators found vitamin D supplementation during early life was not observed to be associated with children’s bone, lean or fat mass.

The investigators concluded vitamin D supplementation during pregnancy or infancy is associated with reduced adiposity (severe or morbid overweight) in childhood. Future large well-designed double blinded RCTs are needed to assess the effectiveness of vitamin D supplementation in early life on children’s bone health, lean mass and adiposity.

Original title:
Effect of Vitamin D Supplementation in Early Life on Children's Growth and Body Composition: A Systematic Review and Meta-Analysis of Randomized Controlled Trials by Ma K, Wei SQ, [...], Wen SW.

Link:
https://www.mdpi.com/2072-6643/13/2/524/htm

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Objectives:
Genistein (4',5,7-trihydroxyisoflavone) is a phytoestrogen with potential health benefits in the prevention of cardiovascular disease. However, the evidence regarding its effects on hypertension has not been conclusive. Therefore, this review article has been conducted.

Do genistein supplements reduce blood pressure?

Study design:
This review article included 4 RCTs (4 treatment arms).

Results and conclusions:
The investigators found genistein supplements did not show any significant reduction of systolic blood pressure [WMD = -5.32 mmHg, 95% CI = -14.59 to 3.96] and diastolic blood pressure [WMD = -2.06 mmHg, 95% CI = -6.41 to 2.28] compared to that of the placebo group.

The investigators found, however, subgroup analysis by intervention duration showed that more than 6 months genistein supplementation in metabolic syndrome patients significantly decreased systolic blood pressure [WMD = -13.73 mmHg, 95% CI = -18.10 to -9.37] and diastolic blood pressure [WMD = -5.18 mmHg, 95% CI = -6.62 to -3.74].

The investigators concluded genistein supplementation of more than 6 months reduces blood pressure among metabolic syndrome patients.

Original title:
Effects of genistein on blood pressure: A systematic review and meta-analysis by Hemati N, Asis M, […], Abdollahi M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31955737

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Objectives:
The relationship between serum copper (Cu) level and overweight/obesity remains controversial. Therefore, this review article (meta-analysis) has been conducted.

Does a high serum copper level increase overweight/obesity risk?

Study design:
This review article included 21 articles.

Results and conclusions:
The investigators found compared with controls, serum copper level was significantly higher in obese children [SMD = 0.74, 95% CI = 0.16 to 1.32] and in obese adults [SMD = 0.39, 95% CI = 0.02 to 0.76].

The investigators found no significant difference in serum copper level between overweight and control groups in children [SMD = 1.52, 95% CI = -0.07 to 3.12] and in adults [SMD = 0.16, 95% CI = -0.06 to 0.38].

The investigators found subgroup analysis revealed a higher serum copper level in obese children [SMD = 0.90, 95% CI = 0.36 to 1.45] and obese adults [SMD = 0.47, 95% CI = 0.05 to 0.88] compared with healthy weight controls.

The investigators found the SMD differed significantly between obese children diagnosed by weight-for-height and controls [SMD = 1.56, 95% CI = 0.57 to 2.55] and there was a significant difference of serum copper level between obese adults diagnosed by BMI (WHO) and controls [SMD = 0.54, 95% CI = 0.08 to 1.01].

The investigators concluded that a higher serum copper level increases risk of obesity in children and adults and these findings need to be further confirmed.

Original title:
The Relationship Between Serum Copper and Overweight/Obesity: a Meta-analysis by Gu K, Li X, […], Jiang X.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31300957

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Objectives:
Does consumption of fruit or vegetables reduce risk of metabolic syndrome (MetS)?

Study design:
This review article included 9 observational studies (7 cross-sectional studies and 2 cohort studies).

Results and conclusions:
The investigators found in a dose-response analysis of 2 cohort studies and 7 cross-sectional studies, that an increase of 100 g/d in fruit consumption significantly reduced risk of metabolic syndrome with 3% [OR = 0.97, 95% CI = 0.95 to 0.99, I2 = 26.7%], whereas an increase of 100 g/d in vegetable consumption (9 studies) was not associated with a reduction in the metabolic syndrome [OR = 0.98, 95% CI = 0.96 to 1.01, I2 = 54.6%].

The investigators concluded 100 g/d fruit consumption reduces risk of metabolic syndrome. However, prospective studies or randomised clinical trials are needed to identify the effects of fruits by variety on the risk of the metabolic syndrome.

Original title:
Fruit and vegetable consumption and the metabolic syndrome: a systematic review and dose-response meta-analysis by Lee M, Lim M and Kim J.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31514758

Additional information of El Mondo:
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Objectives:
The lipid distribution in people who are overweight and obese is directly related to metabolic diseases. Quercetin supplementation may be an appropriate approach for reducing the risk factors of metabolic diseases in people who are obese. Therefore, this review article has been conducted.

Does quercetin supplementation reduce risk factors of metabolic diseases in people who are obese?

Study design:
This review article included 5 RCTs.

Results and conclusions:
The investigators found ≥150 mg/day quercetin supplementation during >6 weeks significantly reduced LDL-cholesterol (bad cholesterol) levels in people who are obese [SMD = -0.8, 95% CI = -1.21 to -0.39, p 0.00001].

The investigators concluded ≥150 mg/day quercetin supplementation during >6 weeks reduces LDL-cholesterol levels in people who are obese.

Original title:
Quercetin Actions on Lipid Profiles in Overweight and Obese Individuals: A Systematic Review and Meta-analysis by Guo W, Gong X and Li M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31465275

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Objectives:
L-carnitine plays a fundamental biological role in the metabolism of lipids and may positively affect blood pressure by decreasing insulin resistance, although the latter remains less clear. Therefore, this review article has been conducted.

Does L-carnitine supplementation reduce blood pressure?

Study design:
This review article included 10 RCTs using a random-effects model to estimate the pooled effect sizes of L-carnitine supplementation on systolic (SBP) and diastolic blood pressure (DBP).

Results were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI).

No evidence of publication bias was observed about the effects of L-carnitine supplementation on systolic blood pressure [p = 0.307] and diastolic blood pressure [p = 0.729], as evidenced by the results of the Egger's test.

Results and conclusions:
The investigators found L-carnitine supplementation decreased diastolic blood pressure [WMD = -1.162 mmHg, 95% CI = -2.020 to -0.303, p = 0.008] without changing systolic blood pressure levels [WMD = -0.085 mmHg, 95% CI = -1.455 to 1.285, p = 0.903].

The investigators found results of subgroup analyses revealed L-carnitine supplementation decreased diastolic blood pressure levels in participants with overweight and obesity [WMD = -1.232 mmHg, 95% CI = -2.297 to -0.167, p = 0.023] and with doses of 2 g/d [WMD = -1.639 mmHg, 95% CI = -3.038 to -0.240, p = 0.022].

The investigators concluded that 2 g/d L-carnitine supplementation decreases diastolic blood pressure in participants with overweight and obesity. However, more research is required to determine the molecular mechanism underlying the relationship between of L-carnitine on blood pressure.

Original title:
Effects of L-carnitine supplementation on blood pressure: a systematic review and meta-analysis of randomized controlled trials by Askarpour M, Hadi A, […], Ghaedi E.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31481697

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

Objectives:
Epidemiological investigations evaluating the association of dietary calcium intake with metabolic syndrome (MetS) risk have yielded controversial results. Therefore, this review article has been conducted.

Does dietary calcium intake reduce risk of metabolic syndrome?

Study design:
This review article included a total 15 cross-sectional studies for dietary calcium intake.

Results and conclusions:
The investigators found for the highest versus lowest category of dietary calcium intake, a significantly reduced risk of 20% [combined OR = 0.80, 95% CI = 0.70 to 0.91] for metabolic syndrome.

The investigators found in dose-response analysis, a non-linear relationship between dietary intake of calcium and risk of metabolic syndrome [p non-linearity > 0.001].

The investigators found 280 mg/d dietary calcium intake significantly reduced risk of metabolic syndrome with 13% [OR = 0.87, 95% CI = 0.82 to 0.93].

The investigators concluded 280 mg/d dietary calcium intake may reduce risk of metabolic syndrome. May reduce because this review article only included cross-sectional studies and no cohort studies. Therefore, these findings should need to be further confirmed by larger prospective cohort studies.

Original title:
Dietary calcium intake and the risk of metabolic syndrome: evidence from observational studies by Cheng L, Hu D and Jiang W.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30846011

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

Objectives:
Is there a relationship between the intake of foods (whole grains, refined grains, vegetables, fruit, nuts, legumes, eggs, dairy, fish, red meat, processed meat and sugar-sweetened beverages) and risk of general overweight/obesity, abdominal obesity and weight gain?

Study design:
This review article included 25 prospective cohort studies until August 2018.
In detail, 6 prospective cohort studies were included in the meta-analysis for consumption of whole grains, 4 studies for refined grains, 7 for vegetables, 6 for fruit, 4 for nuts, 2 for legumes, 2 for eggs, 11 for dairy products, 4 for fish, 4 for red meat, 2 for processed meat and 9 for sugar-sweetened beverages.

Results and conclusions:
The investigators found in the dose-response meta-analysis a significantly reduced risk of 7% per each increase of 30g/d whole-grain products [RR overweight/obesity = 0.93, 95% CI = 0.89 to 0.96, I2 = 0%].
There was no indication for a nonlinear association between whole-grain intake and risk of overweight/obesity [p-nonlinearity = 0.16].

The investigators found in the dose-response meta-analysis a significantly reduced risk of 7-9% per each increase of 100g/d fruit consumption [RR overweight/obesity = 0.93, 95% CI = 0.86 to 1.00, I2 = 89% and RR weight gain = 0.91, 95% CI = 0.86 to 0.97, I2 =7%].
There was no indication of a nonlinear relation [p-nonlinearity = 0.17, p-nonlinearity = 0.14, respectively].

The investigators found in the dose-response meta-analysis a significantly reduced risk of 58% per each increase of 28g/d nut consumption [RR abdominal obesity = 0.42, 95% CI = 0.31 to 0.57].

The investigators found in the dose-response meta-analysis a significantly reduced risk of 12% per each increase of 50g/d legume consumption [RR overweight/obesity = 0.88, 95% CI = 0.84 to 0.93].

The investigators found in the dose-response meta-analysis a significantly reduced risk of 17% per each increase of 100g/d fish consumption [RR abdominal obesity = 0.83, 95% CI = 0.71 to 0.97, I2 = 0%].
There was no indication of nonlinearity [p-nonlinearity = 0.07], but the graph indicated a stronger risk reduction at lower levels of fish intake and the curve reached a plateau at ∼40 g/d.

The investigators found in the dose-response meta-analysis a significantly increased risk of 5% per each increase of 30g/d refined grains consumption [RR overweight/obesity = 1.05, 95% CI = 1.00 to 1.10, I2 = 61%].
However, the nonlinear dose-response meta-analysis indicated that the association had a J-shape curve and a higher risk of overweight/obesity was identified for an intake of refined grains >90 g/d [p-nonlinearity 0.001].

The investigators found in the dose-response meta-analysis a significantly increased risk of 10-14% per each increase of 30g/d red meat consumption [RR abdominal obesity = 1.10, 95% CI = 1.04 to 1.16, I2 = 0% and RR weight gain = 1.14, 95% CI = 1.03 to 1.26].

The investigators found in the dose-response meta-analysis a significantly increased risk of 5-12% with each increase of 250 mL sugar-sweetened beverages per day consumption [RR overweight/obesity = 1.05, 95% CI = 1.00 to 1.11 and RR abdominal obesity = 1.12, 95% CI = 1.04 to 1.20, I2 = 38%].  
The increase in risk was stronger at lower amounts of sugar-sweetened beverages intake (until ∼300 mL/d), but an increase at higher intakes was still present [p-nonlinearity = 0.03].

The investigators found the intake of 5 servings of whole grains/d, 3 servings of vegetables/d and 3 servings of fruit/d significantly resulted in a 38% reduction in risk of overweight/obesity compared with non-consumption of these food groups.

The investigators found the intake of 5 servings of refined grains/d and 3 servings of sugar-sweetened beverages/d significantly resulted in a 59% increased risk of overweight/obesity.

The investigators concluded that high intakes of whole grains, vegetables, fruit and probably fish as well as a low intake of refined grains, red meat and sugar-sweetened beverages are associated with a reduced risk of measures of adiposity, including overweight/obesity, abdominal obesity or weight gain, respectively. These findings are in line with current public health recommendations regarding a health-promoting diet. However, with the current evidence rated as very low to low, findings should be interpreted with caution and better-designed observational studies, more evidence from intervention trials and use of novel statistical methods (e.g., substitution analyses or network meta-analyses) are needed.

Original title:
Food Groups and Risk of Overweight, Obesity, and Weight Gain: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies by Schlesinger S, Neuenschwander M, […], Schwingshackl BH.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6416048/

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

Objectives:
Is there a relationship between nut consumption and metabolic syndrome (MetS)?

Study design:
This review article included a total of 11 observational studies (6 cross-sectional and 5 prospective cohort studies), which involved a total of 89,224 participants.

Results and conclusions:
The investigators found nut consumption significantly reduced risk of metabolic syndrome with 16% [overall multivariable adjusted RR = 0.84, 95% CI = 0.76-0.92, p  0.001].

The investigators found in subgroup analysis tree nut consumption significantly reduced risk of metabolic syndrome with 3% [RR = 0.97, 95% CI = 0.94-1.00, p =0.04]. However, this reduced risk was not significant in peanuts [RR = 1.01, 95% CI = 0.96-1.06, p = 0.68].

The investigators concluded nut consumption reduces risk of metabolic syndrome. However, this reduced risk is only found in tree nuts, not in peanuts. More well-designed studies with detailed specifications of nut varieties are needed to further elaborate the issues examined in this meta-analysis.

Original title:
Relationship Between Nut Consumption and Metabolic Syndrome: A Meta-Analysis of Observational Studies by Zhang Y and Zhang DZ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30716015

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