Nutritional advice

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.

Objectives:
Has flavonoid supplementation potential against obesity?

Study design:
This review article included 58 RCTs.
Analysis endpoints were calculated as the mean difference between baseline and post-treatment.
Flavonoids were in subclasses of flavanols, flavonols, isoflavones, flavanones, anthocyanins and proanthocyanidins. They were mostly in the form of supplements and dosages varying from 40 to 1300 mg/day.

Results and conclusions:
The investigators found among flavonoid subclasses, flavanols showed potential for decreasing BMI, in the overall population [MD = -0.28 kg/m², p = 0.04, n = 21] and in the subgroups of Asians [MD = -0.42 kg/m², p = 0.046, n = 13], ages 50 years [MD = -0.50 kg/m², p = 0.008, n = 14], BMI ≥25 kg/m² [MD = -0.30 kg/m², p = 0.049, n = 15] and at doses ≥500 mg/day [MD = -0.36 kg/m², p = 0.049, n = 12].

The investigators found among flavonoid subclasses, isoflavones also significantly decreased BMI of non-Asian populations [MD = -0.26 kg/m², p = 0.035, n = 13] and doses ≥75 mg/day [MD = -0.34 kg/m², p = 0.027, n = 8].

The investigators found in the overall assessment, flavanols also significantly decreased waist circumference [MD = -0.60 cm, p = 0.02, n = 18] but had no significant effect on body fat percentage.

The investigators found the available trials did not reveal significant effects from flavonols, flavanones and anthocyanins on the specified anthropometric measures.

The investigators concluded that flavanols, particularly ≥500 mg/day and isoflavones, particularly ≥75 mg/day have potential against obesity.

Original title:
Flavanols are potential anti-obesity agents, a systematic review and meta-analysis of controlled clinical trials by Akhlaghi M, Ghobadi S, […], Mohammadian F.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29759310

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

Objectives:
Carbohydrate-restricted diets may increase low-density lipoprotein cholesterol (LDL-cholesterol or bad cholesterol) and thereby cardiovascular risk. Therefore, this review article has been conducted.

Do carbohydrate restriction diets increase cholesterol and triglycerides levels in overweight/obese adults?

Study design:
This review article included 8 RCTs with a total of 1,633 participants, of which 818 in carbohydrate-restricted diet group (intervention group) and 815 low-fat diet group (control group).

All RCTs had more than 100 participants with duration of at least 6 months.

Results and conclusions:
The investigators found when compared with low-fat diets, carbohydrate-restricted diets showed no significant difference in LDL-cholesterol levels after 6, 12 and 24 months.
Although an overall pooled analysis statistically favoured low-fat diets [0.07 mmol/L, 95% CI = 0.02-0.13, p = 0.009], this was clinically insignificant.

The investigators found when compared with low-fat diets, carbohydrate-restricted diets significant increased HDL-cholesterol (good cholesterol) levels [0.08 mmol/L, 95% CI = 0.06-0.11, p 0.00001] after 6 and 12 months.
These favourable changes were more marked in the subgroup with very-low carbohydrate content [50 g/d: 0.12 mmol/L, 95% CI = 0.10-0.14, p  0.00001].

The investigators found when compared with low-fat diets, carbohydrate-restricted diets significant reduced plasma triglycerides levels [-0.13 mmol/L, 95% CI = -0.19 to -0.08, p  0.00001 after 6 and 12 months.
These favourable changes were more marked in the subgroup with very-low carbohydrate content [50 g/d: -0.19 mmol/L, 95% CI = -0.26 to -0.12, p = 0.02].

The investigators concluded large randomized controlled trials (RCTs) of at least 6 months duration with carbohydrate restriction, particularly 50 g/d carbohydrates, is superior in improving HDL-cholesterol and triglycerides levels in overweight/obese adults when compared with low-fat diets. Dietary guidelines should consider carbohydrate restriction as an alternative dietary strategy for the prevention/management of dyslipidemia for populations with cardiometabolic risk.

Original title:
Effects of carbohydrate-restricted diets on low-density lipoprotein cholesterol levels in overweight and obese adults: a systematic review and meta-analysis by Gjuladin-Hellon T, Davies IG, […], Amiri Baghbadorani R.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30544168

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

50 grams of carbohydrates per day corresponds to a diet with 10 En% carbohydrates.
The easiest way to follow a diet with 10 En% carbohydrates is to choose only meals/products with 10 En% carbohydrates.
However, the most practical way to follow a diet with 10 En% carbohydrates is all meals/products that you eat on a daily basis should contain on average 10 En% carbohydrates. Check here which products contain 10 En% carbohydrates.

Objectives:
Cocoa and dark chocolate (DC) have been reported to be effective for health promotion; however the exact effect of cocoa/dark chocolate on anthropometric measures have not been yet defined. Therefore, this review article has been conducted.

Has cocoa/dark chocolate supplementation positive effect on weight, BMI and waist circumference (WC)?   

Study design:
This review article included a total of 35 RCTs, investigating the effects of cocoa/dark chocolate on weight, BMI and waist circumference.

Results and conclusions:
The investigators found meta-analysis did not suggest any significant effect of cocoa/dark chocolate supplementation on:
-body weight [-0.108 kg, 95% CI = -0.262 to 0.046 p = 0.168]
-BMI [-0.014 kg/m², 95% CI = -0.105 to 0.077, p = 0.759] and
-WC [0.025 cm, 95% CI = -0.083 to 0.129, p = 0.640].

The investigators found, however, subgroup analysis revealed that weight and BMI were significantly reduced with ≥ 30g chocolate per day during 4-8 weeks.

Furthermore, supplementation of ≥ 30g chocolate per day during 4-8 weeks significantly reduced waist circumference in non-linear fashion [r = 0.042, p-nonlinearity = 0.008].

The investigators concluded that ≥ 30g chocolate per day during 4-8 weeks reduce weight, BMI and waist circumference.

Original title:
Does cocoa/dark chocolate supplementation have favorable effect on body weight, body mass index and waist circumference? A systematic review, meta-analysis and dose-response of randomized clinical trials by Kord-Varkaneh H, Ghaedi E, […], Shab-Bidar S.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29553824

Additional information of El Mondo:
Find more information/studies on meta-analysis, chocolate consumption and overweight right here.

Objectives:
Modifiable factors that reduce the burden of the metabolic syndrome (MetS), particularly plant-derived biomarkers, have been a recent focus of rising interest. Therefore, this review article has been conducted.

Do dietary carotenoids reduce risk of metabolic syndrome?  

Study design:
This review article included 11 cross-sectional studies.
Publication bias was absent and harvest plots indicated consistency upon replication for β-carotene and total carotenoid exposures.

Results and conclusions:
The investigators found dietary total carotenoids intake significantly reduced risk of metabolic syndrome with 44% [pooled OR = 0.66, 95% CI = 0.56-0.78, 1 SD ∼ 0.82 µmol/L, n = 5 studies]. This reduced risk was the strongest for β-carotene, followed by α-carotene and β-crypotoxanthin.

The investigators found no association between retinol (vitamin A from animal products) and risk of metabolic syndrome [pooled OR = 1.00, 95% CI = 0.88-1.13, 1 SD ∼ 2.14 µmol/L, n = 6 studies].

The investigators concluded that carotenoids, particularly β-carotene, followed by α-carotene and β-crypotoxanthin may reduce risk of metabolic syndrome. May reduce because this review article only included cross-sectional studies and no cohort studies.

Original title:
Carotenoids, vitamin A, and their association with the metabolic syndrome: a systematic review and meta-analysis by Beydoun MA, Chen X, [...], Canas JA.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30202882

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

Objectives:
What are the effects of ginger intake on weight loss, glycemic control and lipid profiles among overweight (BMI>25) and obese (BMI>30) subjects?

Study design:
This review article included 14 RCTs with in total of 473 subjects.

Results and conclusions:
The investigators found that supplementation with ginger significantly decreased among overweight (BMI>25) and obese (BMI>30) subjects:
-body weight (BW) [SMD -0.66, 95% CI = -1.31 to -0.01, p = 0.04];
-waist-to-hip ratio (WHR) [SMD = -0.49, 95% CI = -0.82 to -0.17, p = 0.003];
-hip ratio (HR) [SMD = -0.42, 95% CI = -0.77 to -0.08, p = 0.01];
-fasting glucose [SMD = -0.68, 95% CI = -1.23 to -0.05, p = 0.03] and;
-insulin resistance index (HOMA-IR) [SMD= -1.67, 95% CI = -2.86 to -0.48, p = 0.006].

The investigators found that supplementation with ginger significantly increased HDL-cholesterol (good cholesterol) levels [SMD = 0.40, 95% CI = 0.10 to 0.70, p = 0.009] among overweight (BMI>25) and obese (BMI>30) subjects.

The investigators found, however, that supplementation with ginger had no detrimental effect on:
-body mass index (BMI) [SMD = -0.65, 95% CI = -1.36 to 0.06, p = 0.074];
-insulin [SMD = -0.54, 95% CI = -1.43 to 0.35, p = 0.23];
-triglycerides [SMD = -0.27, 95% CI = -0.71 to 0.18, p = 0.24];
-total cholesterol [SMD = -0.20, 95% CI = -0.58 to 0.18, p = 0.30] and;
-LDL-cholesterol [SMD = -0.13, 95% CI = -0.51 to 0.24, p = 0.48].

The investigators concluded that ginger intake reduces body weight, waist-to-hip ratio, hip ratio, fasting glucose and insulin resistance index and increases HDL-cholesterol (good cholesterol), but has no affect on insulin, BMI, triglycerides, total- and LDL-cholesterol (bad cholesterol) levels among overweight and obese subjects.

Original title:
The effects of ginger intake on weight loss and metabolic profiles among overweight and obese subjects: A systematic review and meta-analysis of randomized controlled trials by Maharlouei N, Tabrizi R, […], Asemi Z.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29393665

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

Persons with overweight are advised to choose products/meals with maximum 30 En% fat, maximum 7 En% saturated fat, maximum 0.2 grams salt per 100 kcal and minimum 1.5 grams fiber per 100 kcal. Check here which products/meals are suitable for persons with overweight.
 

Objectives:
Does vegetable and/or fruit consumption reduce metabolic syndrome (MetS)?

Study design:
This review article included 20 cross-sectional studies, 1 case-control study and 5 cohort studies.

Results and conclusions:
The investigators found in 16 studies when comparing the highest versus the lowest category of vegetable consumption a significantly reduced risk of 11% [overall multivariable-adjusted RR = 0.89, 95% CI = 0.85-0.93, p 0.001] for metabolic syndrome.

The investigators found in 16 studies when comparing the highest versus the lowest category of fruit consumption a significantly reduced risk of 19% [overall multivariable-adjusted RR = 0.81, 95% CI = 0.75-0.88, p 0.001] for metabolic syndrome.

The investigators found in 8 studies when comparing the highest versus the lowest category of vegetable and fruit consumption a significantly reduced risk of 25% [overall multivariable-adjusted RR = 0.75, 95% CI = 0.63-0.90, p = 0.002] for metabolic syndrome.

The investigators concluded that vegetable and/or fruit consumption is negatively associated with metabolic syndrome. However, more well-designed prospective cohort studies are needed to elaborate the concerned issues further.

Original title:
Associations of vegetable and fruit consumption with metabolic syndrome. A meta-analysis of observational studies by Zhang Y and Zhang DZ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29506604

Additional information of El Mondo:
Find more information/studies on overweight and fruit and vegetable consumption 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:
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 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:
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:
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:
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

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

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

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

Find out whether you are overweight or not 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.  

Click here to find out whether you are overweight or not?

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

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

Objectives:
Emerging randomized controlled trials (RCTs) investigating the effect of green tea or green tea extract (GTE) supplementation on blood pressure (BP) among overweight and obese adults reported inconsistent findings. Therefore, this review article has been conducted.

Does tea consumption decrease blood pressure among overweight and obese adults?

Study design:
This review article included 14 RCTs with 971 participants (47% women).

Results and conclusions:
The investigators found green tea or green tea extract supplementation compared with placebo, significantly reduced systolic blood pressure with 1.42 mmHg [95% CI = -2.47 to -0.36, p  =  0.008, I2  =  52%, p for heterogeneity =  0.01 ] among overweight and obese adults.

The investigators found green tea or green tea extract supplementation compared with placebo, significantly reduced diastolic blood pressure with 1.25 mmHg [95% CI = -2.32 to -0.19, p = 0.02, I2 = 74%, p for heterogeneity   0.001] among overweight and obese adults.

The investigators found the quality of evidence across studies was low. Similar results were found in subgroup and sensitivity analyses.

The investigators concluded among overweight and obese adults, green tea or green tea extract supplementation is found to cause a small but significant reduction in blood pressure. However, more high-quality RCTs with large sample sizes are needed to further confirm the efficacy on blood pressure and make strong recommendations for green tea or green tea extract supplementation among the overweight and obese adults.

Original title:
Effect of green tea supplementation on blood pressure among overweight and obese adults: a systematic review and meta-analysis by Li G, Zhang Y, […], Holbrook A.

Link:
http://journals.lww.com/jhypertension/Abstract/2015/02000/Effect_of_green_tea_supplementation_on_blood.6.aspx

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

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

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

Objectives:
Controversy persists regarding the effect of mixtures of conjugated linoleic acids (c9,t11- and t12,c10-CLA) in fasting blood glucose (FBG) and waist circumference (WC) in humans. Therefore, this review article (meta-analysis) has been conducted.

Does CLA reduce fasting blood glucose (FBG) and waist circumference (WC) in humans?

Study design:
This review article included 32 randomized clinical trials.

Results and conclusions:
The investigators found subgroup analysis showed that taking CLA supplement did not significantly influence fasting blood glucose [SMD = 0.075 mg/dL, 95% CI = -0.099 to 0.249, p = 0.399].

The investigators found subgroup analysis showed that taking CLA supplement reduced non-significantly waist circumference with 0.149cm [SMD = -0.149cm, 95% CI = -0.522 to 0.225, p = 0.435].

The investigators found foods enriched in CLA also showed no significant effect on fasting blood glucose [SMD = 0.126 mg/dL, 95% CI = -0.100 to 0.352, p = 0.274].

The investigators found foods enriched in CLA also showed no significant effect on waist circumference [SMD = -0.233cm, 95% CI = -0.625 to 0.159, p = 0.244].

The investigators concluded that c9,t11- and t12,c10-CLA administered as a supplement or used to enrich foods does not reduce fasting blood glucose (FBG) and waist circumference (WC) in humans.

Original title:
Effect of conjugated linoleic acid as a supplement or enrichment in foods on blood glucose and waist circumference in humans: A meta-analysis by Rahbar AR, Ostvar A, […], Rahbar A.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28176632

Additional information of El Mondo:
Find more information/studies on overweight and fat consumption right here.
Overweight people often have higher fasting blood glucose (FBG) and greater waist circumference (WC).

Find here whether you are overweight or not?

Conjugated linoleic acids (CLA) are a family of isomers of linoleic acid found mostly in meat and dairy products derived from ruminants. An average daily diet supplies 15-174mg of conjugated linoleic acid.

Chemical structures of CLA.