Nutrition and health

Objectives:
Fish oil has been shown to reduce the risk of metabolic disorders. However, the effects of fish oil intervention on glucose metabolism and insulin sensitivity are still controversial, especially in children. Therefore, this review article has been conducted.

Do fish oil supplements (EPA + DHA) improve insulin sensitivity in children?

Study design:
This review article included 13 RCTs with 567 children in placebo group (group without fish oil supplements) and 565 in fish oil group (intervention group).

No heterogeneity was found for the pooled and subgroup analyses.

Results and conclusions:
The investigators found compared with the placebo group, fish oil intervention had beneficial effects on insulin sensitivity in the pooled analysis [WMD = -0.219, 95% CI = -0.392 to -0.046, p = 0.013].

These beneficial effects were also found in subgroup analyses, when the fish oil intervention period was short-term (≤6 months) low dose (eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) dose 1.5 g/day) and high ratio (eicosapentaenoic acid to docosahexaenoic acid ≥1).

The investigators concluded fish oil supplements, especially 1.5 g/day EPA + DHA during 6 months, improve insulin sensitivity in children.

Original title:
Effect of Fish Oil on Insulin Sensitivity in Children: A Systematic Review and Meta-Analysis of Randomized, Controlled Trials by Hou M, Zhou W, [...], Lv H.

Link:
https://pubmed.ncbi.nlm.nih.gov/33388274/

Additional information of El Mondo:
Find more information/studies on EPA + DHA and diabetes right here.
 

Objectives:
Does a high dietary cholesterol intake increase risk of gestational diabetes mellitus?

Study design:
This review article included 3 cohort studies, 4 cross-sectional studies and 2 case-control studies involving 30,123 participants and 3,237 women with gestational diabetes mellitus (diabetes mellitus in pregnancy).

Results and conclusions:
The investigators found comparing highest versus lowest category of dietary cholesterol intake, that the highest dietary cholesterol intake significantly increased risk of gestational diabetes mellitus with 49% [pooled RR = 1.49, 95% CI = 1.18 to 1.88].

The investigators found in dose-response analysis that the risk of gestational diabetes mellitus significantly increased by 32% [RR = 1.32, 95% CI = 1.20 to 1.45] for every increase of 100 mg per day in dietary cholesterol intake.

The investigators concluded a high dietary cholesterol intake (at least 100 mg per day) increases risk of gestational diabetes mellitus.

Original title:
Dietary Cholesterol Intake and Risk of Gestational Diabetes Mellitus: A Meta-Analysis of Observational Studies by Gao F and Cui CY.

Link:
https://pubmed.ncbi.nlm.nih.gov/33416437/

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

Objectives:
Does type 1 diabetes mellitus (T1DM) decrease bone mineral density (BMD) in children and adolescents?

Study design:
This review article included 9 cross-sectional studies with a total of 1,522 children and adolescents.

Funnel plot and the Egger test did not reveal significant publication bias.

Results and conclusions:
The investigators found a significant decrease in bone mineral density Z-score in the whole body [pooled WMD = -0.47, 95% CI = -0.92 to -0.02, I2 = 80.2%] and lumbar spine [pooled WMD = -0.41, 95% CI = -0.69 to -0.12, I2 = 80.3%] in children and adolescents with type 1 diabetes mellitus, which was consistent in published studies from Asia and South America, but inconsistent in the North America and Europe.
Sensitivity analyses did not modify these findings.

The investigators found, importantly, the differences in bone mineral density Z-scores were independent of age, level of glucose control (HbA1c) and prepubertal stage.

The investigators concluded type 1 diabetes mellitus (T1DM) decreases bone mineral density (BMD) Z-scores in the whole body and lumbar spine in children and adolescents.

Original title:
Association between type 1 diabetes mellitus and reduced bone mineral density in children: a meta-analysis by Zhu Q, J Xu J, […], Shi J.

Link:
https://pubmed.ncbi.nlm.nih.gov/33404757/  

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

Objectives:
Type 1 diabetes mellitus (T1DM) causes the irreversible destruction of pancreatic beta cells. The Bacillus Calmette-Guerin (BCG) vaccine can modulate the immune response and decelerate disease progression. Therefore, this review article has been conducted.

Do patients with type 1 diabetes mellitus benefit from the Bacillus Calmette-Guerin (BCG) vaccine?

Study design:
This review article included 4 RCTs. The sample sizes ranged from 6 to 94, with a total of 198 subjects. The mean age of the examinees ranged from 10.1 to 36.0 years and the follow-up duration ranged from 1 to 8 years.

Results and conclusions:
The investigators found the pooled meta-analysis demonstrated no significant difference in HbA1c levels [MD = -0.12, 95% CI = -0.53 to 0.30, I2 = 56%] or fasting C-peptide levels [MD = -0.15, 95% CI = -0.35 to 0.06, I2 = 0%] in the BCG intervention group as compared with that in the placebo group.
The results remained unchanged after removing each study in the sensitivity analysis.

The investigators concluded there is no robust evidence to support the use of the Bacillus Calmette-Guerin (BCG) vaccine for the treatment of type 1 diabetes mellitus although the HbA1c levels tend to improve. Additional RCTs to assess the long-term effects of the Bacillus Calmette-Guerin (BCG) vaccine on glycemic control are warranted.

Original title:
Therapeutic Effects of BCG Vaccination on Type 1 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials by Chang YC, Lin CJ, […], Hsu HY.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7139880/

Additional information of El Mondo:
Find more information/studies on vaccination, diabetes mellitus and malnutrition right here.

Objectives:
Does fish consumption reduce risk of coronary heart disease (CHD), stroke and all-cause mortality in patients with type 2 diabetes (T2D)?

Study design:
This review article included 9 prospective cohort studies with 57,394 diabetic patients.

Results and conclusions:
The investigators found for the highest compared with the lowest category of fish consumption, a significantly reduced risk of 14% [relative risk = 0.86, 95% CI = 0.76 to 0.96, I2 = 50%, n = 8] for all-cause mortality in patients with type 2 diabetes.

The investigators found for the highest compared with the lowest category of fish consumption, a significantly reduced risk of 39% [relative risk = 0.61, 95% CI = 0.29 to 0.93, I2 = 68%, n = 3] for coronary heart disease in patients with type 2 diabetes.

The investigators found there was a monotonic inverse association, with a nadir at fish consumption of approximately 2-3 servings/week, in both analyses.

The investigators concluded 2-3 servings/week of fish consumption reduce risk of all-cause mortality and coronary heart disease in patients with type 2 diabetes.

Original title:
Fish consumption and the risk of cardiovascular disease and mortality in patients with type 2 diabetes: a dose-response meta-analysis of prospective cohort studies by Jayedi A, Soltani S, […], Shab-Bidar S.

Link:
https://pubmed.ncbi.nlm.nih.gov/32410513/

Additional information of El Mondo:
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Objectives:
Probiotics are being used increasingly in pregnant women, whereas the efficiency on pregnancy outcomes is yet lacking. Therefore, this review article has been conducted.

Have probiotic supplements during pregnancy positive effects on pregnancy outcomes, such as eczema, gestational age?

Study design:
This review article included 18 RCTs with a total of 4,356 pregnant women.

Results and conclusions:
The investigators found probiotic supplementation during pregnancy significantly decreased risk of atopic eczema with 32% [RR = 0.68, 95% CI = 0.58 to 0.81, p 0.001, without significant heterogeneity].

The investigators found probiotic supplementation during pregnancy significantly decreased risk of eczema with 21% [RR = 0.79, 95% CI = 0.68 to 0.91, p = 0.002, without significant heterogeneity].

The investigators found probiotic supplementation during pregnancy was associated with a prolonged gestational age [WMD = 0.09, 95 % CI = 0.04 to 0.15, p = 0.001 with insignificant heterogeneity].
However, probiotic supplementation during pregnancy had no significant effect on birth weight [p = 0.851].

The investigators found probiotic supplementation during pregnancy significantly decreased risk of death with 66% [RR = 0.34, 95% CI = 0.13 to 0.91, p = 0.031, without evidence of heterogeneity].

The investigators found probiotic supplementation during pregnancy significantly decreased risk of necrotising enterocolitis (NEC) with 62% [RR = 0.38, 95% CI = 0.18 to 0.11, p = 0.012, without evidence of heterogeneity].

The investigators concluded probiotic supplementation in pregnant women is beneficial for atopic eczema, eczema, gestational age, death and necrotising enterocolitis.

Original title:
Effect of probiotic supplementation in pregnant women: a meta-analysis of randomised controlled trials by Kuang L and Jiang Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31856928

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Necrotizing enterocolitis (NEC) is a devastating disease that affects mostly the intestine of premature infants. The wall of the intestine is invaded by bacteria, which cause local infection and inflammation that can ultimately destroy the wall of the bowel (intestine). Such bowel wall destruction can lead to perforation of the intestine and spillage of stool into the infant’s abdomen, which can result in an overwhelming infection and death.
 

Objectives:
Does niacin (vitamin B3) supplementation improve lipid profiles and glycemic control in patients with type 2 diabetes mellitus?

Study design:
This review article included 8 RCTs comprised a total of 2,110 patients with type 2 diabetes mellitus.
Studies published ranged from 1990 to 2016 and 15 to 1,053 patients were included in each individual trial.

The follow-up duration ranged from 8.0 weeks to 12.0 months.

The study quality was assessed using the Jadad scale. 4 studies had 3 scores and the remaining 4 studies had 2 scores.

There was no significant publication bias.

Results and conclusions:
The investigators found patients’ niacin supplementation was associated with lower levels of total cholesterol [WMD = -0.28, 95% CI = -0.44 to -0.12, p =  0.001], triglyceride [WMD = -0.37, 95% CI = -0.52 to -0.21, p   0 .001] and low-density lipoprotein cholesterol (bad cholesterol) [WMD = -0.42, 95% CI = -0.50 to -0.34, p    0.001].

The investigators found, moreover, the level of high-density lipoprotein cholesterol (good cholesterol) was significantly increased when niacin supplementation [WMD = 0.33, 95% CI = 0.21 to 0.44, p 0 .001] was provided.

The investigators found, however, niacin supplementation produced no significant effects on plasma glucose [WMD = 0.18, 95% CI = -0.14 to 0.50, p = 0 .275] and hemoglobin A1c (HbA1c) levels [WMD = 0.39, 95% CI = -0.15 to 0.94, p = 0 .158].

The investigators concluded that niacin (vitamin B3) supplementation improves lipid profiles, including total cholesterol, LDL and HDL cholesterol without affecting the glycemic levels for patients with type 2 diabetes mellitus. Additional large-scale RCTs should be conducted to evaluate the long-term effectiveness of niacin supplementation.

Original title:
Effectiveness of niacin supplementation for patients with type 2 diabetes: A meta-analysis of randomized controlled trials by Xiang D, Zhang Q and Wang YT.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7373507/

Additional information of El Mondo:
Find more information/studies on cholesterol, vitamin B3 and diabetes right here.
 

Objectives:
Type 2 diabetes mellitus is a chronic disease that occurs among the general population. The insulin-lowering and homeostasis model assessment of insulin resistance-improving effects of inulin are unconfirmed. Therefore, this review article has been conducted.

Do inulin supplements improve HOMA-IR, fasting plasma glucose and HbA1c in patients with type 2 diabetes mellitus?

Study design:
This review article included 9 RCTs with a total of 661 participants.

The duration of the interventions ranged from 6 weeks to 12 weeks and the dosage of inulin supplementation ranged from 8.4 g to 10 g per day.

Results and conclusions:
The investigators found inulin supplementation significantly improved fasting plasma glucose [SMD = -0.55, 95% CI = -0.73 to -0.36, p = 0.0], HOMA-IR [SMD = -0.81, 95% CI = -1.59 to -0.03, p = 0.042] and HbA1c [SMD = -0.69, 95% CI = -0.92 to -0.46, p = 0.0] in patients with type 2 diabetes mellitus.

The investigators found, further subgroup analyses revealed a significant role of inulin supplementation for treatment durations ≥8 weeks [p = 0.038 for insulin, p = 0.002 for HOMA-IR, p = 0.032 for fasting plasma glucose, p = 0 for HbA1c] in patients with type 2 diabetes mellitus.

The investigators concluded that daily 8.4-10 grams of inulin supplements for at least 8 weeks improve HOMA-IR, fasting plasma glucose and HbA1c in patients with type 2 diabetes mellitus.

Original title:
Efficacy of inulin supplementation in improving insulin control, HbA1c and HOMA-IR in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials by Zhang W, Tang Y, […], Hu H.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7263925/

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Inulin is a type of fiber that's found in certain plant foods. Chicory root is the main source of inulin in supplement form.

Objectives:
Antioxidant status is considered as important factor in the pathogenesis (the manner of development of a disease) of vitiligo. However, there are controversial findings about serum status of antioxidants in vitiligo patients. Therefore, this review article has been conducted.

Is there a relationship between serum antioxidant level (e.g. vitamin C, E, zinc and selenium) and risk of vitiligo?

Study design:
This review article included 11 studies including 570 vitiligo cases and 580 controls (people without vitiligo).

Serum vitamin A and copper level in vitiligo patients were only evaluated in single studies and not included in meta-analysis.

Results and conclusions:
The investigators found based on fixed effect model, there were no statistical difference between two groups regarding serum vitamin C levels [OR = 1.17, 95% CI = 0.74 to 1.84, p = 0.495] and serum vitamin E levels [OR = 0.61, 95% CI = 0.30 to 1.25, p = 0.180].

The investigators found in sensitivity analysis, higher serum zinc levels significantly decreased risk of vitiligo with 71% [OR = 0.29, 95% CI = 0.15 to 0.54, p 0.001].

The investigators found in sensitivity analysis, higher serum selenium level significantly increased risk of vitiligo with 331% [OR = 4.31, 95% CI = 2.72 to 6.81, p 0.001].

The investigators concluded that higher serum selenium and lower zinc level increase risk of vitiligo. Potential mechanism associated with preventive effects of zinc and the depigmentation effect of selenium should be more elucidated in further studies.

Original title:
Serum Level of Antioxidant Vitamins and Minerals in Patients With Vitiligo, a Systematic Review and Meta-Analysis by Huo J, Liu T, [...], Wang R.

Link:
https://pubmed.ncbi.nlm.nih.gov/32593085/

Additional information of El Mondo:
Find here more information/studies about antioxidants, selenium and zinc.

Vitiligo is a long-term condition where pale white patches develop on the skin. It's caused by the lack of melanin, which is the pigment in skin. Vitiligo can affect any area of skin, but it commonly happens on the face, neck and hands and in skin creases.

Objectives:
Does barberry (Berberis vulgaris L.) supplementation improve glycemic markers including fasting blood sugar (FBS) concentrations, insulin levels, homeostatic model assessment for insulin resistance (HOMA-IR) and glycosylated hemoglobin (HbA1c) percentage?

Study design:
This review article included 7 RCTs, comprising 452 participants.

Results and conclusions:
The investigators found the meta-analysis revealed that barberry supplementation significantly reduced insulin levels [Hedges’s = -0.67, 95% CI = -1.31 to -0.03, p = 0.04, I2 = 73.3%].
However, no significant positive effect was observed for fasting blood sugar levels [WMD = -8.06 mg/dL, 95% CI = -20.46 to 4.33, p = 0.23, I2 = 96.1%], HbA1c percentage [WMD = -0.83%, 95% CI = -2.33 to 0.67, p = 0.27, I2 = 88.3%] and HOMA-IR index [WMD = -0.55, 95% CI = -1.60 to 0.50, p = 0.30, I2 = 99.4%].

The investigators concluded barberry supplementation improves insulin levels.

Original title:
The Effect of Barberry (Berberis Vulgaris L.) on Glycemic Indices: A Systematic Review and Meta-Analysis of Randomized Controlled Trials by Safari Z, Farrokhzad A, […], Askari G.

Link:
https://www.sciencedirect.com/science/article/abs/pii/S0965229920302235?via%3Dihub

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

Objectives:
Do higher gestational vitamin D levels (vitamin D levels of the mother during pregnancy) decrease risk of multiple sclerosis (MS) in offspring?

Study design:
This review article included 4 case-control studies of moderate to low risk of bias.

Factors identified as determinants of heterogeneity were the definitions of vitamin D deficiency, the characteristics of study participants and the quality of the study.

Results and conclusions:
The investigators found that higher levels of gestational vitamin D significantly reduced risk of multiple sclerosis in offspring with 37% [OR = 0.63, 95% CI = 0.47 to 0.84] in random effects models and in a stratified analysis based on study quality.

The investigators concluded higher levels of gestational vitamin D reduce risk of multiple sclerosis in offspring.

Original title:
Gestational vitamin D and offspring risk of multiple sclerosis: a systematic review and meta-analysis by Jasper EA, Nidey NL, […], Ryckman KK.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32014337

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

 

Objectives:
Micronutrients’ deficiency is a common phenomenon among a majority of the population residing in the low- and middle-income countries (LMICs) especially among women and children. Given the widespread prevalence of micronutrients’ deficiency in LMICs, iron-fortified foods could be of potential benefits for both the mother and the development of fetus. Therefore, this review article has been conducted.

Does iron fortification increase hemoglobin (Hb) concentration during pregnancy and have iron fortification positive effects on specific maternal and pregnancy outcomes?

Study design:
This review article included 12 RCTs (n = 3,872).

The weighted mean difference (WMD) and relative risk (RR) were calculated using random-effects models. Sources of heterogeneity were explored through meta-regression.

The funnel plot was symmetrical, indicating that there was absence of any publication bias which was confirmed using Egger's weighted regression method [Egger test, ρ = 0.69].

Results and conclusions:
The investigators found the mean change in hemoglobin concentration was significantly higher in the group of mothers with iron fortification when compared with the control group [WMD = 4.45 g/L, 95% CI = 2.73 to 6.17 g/L, I2 = 83%, ρ 0.00001].

The investigators found in meta-regression analysis that the duration of feeding was positively associated with the effect size.

The investigators concluded iron fortification increases hemoglobin (Hb) concentration during pregnancy. Further research is required to explore the benefits of iron fortification on maternal and neonatal health outcomes during pregnancy.

Original title:
Meta-analysis Approach on Iron Fortification and Its Effect on Pregnancy and Its Outcome Through Randomized, Controlled Trials by Athe R, Dwivedi R, […], Banset U.  

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7114015/

Additional information of El Mondo:
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Objectives:
A low insulin-like growth factor 1 (IGF-1) level is known to be associated with many disorders. Several studies have shown that soy consumption may influence IGF-1, but the findings remain inconclusive. Therefore, this review article (meta-analysis) has been conducted.

Does soy consumption increase insulin-like growth factor 1 (IGF-1) level?

Study design:
This review article included 8 clinical trials.

Results and conclusions:
The investigators found, overall, a significant increment in plasma IGF-1 was observed following soy intervention [WMD = 13.5 ng/mL, 95% CI = 5.2 to 21.8, I2 = 97%].

The investigators found, subgroup analyses demonstrated a significantly greater increase in IGF-1, when soy was administered at a dosage of ≤40 g/day [WMD = 11.7 ng/mL, 95% CI = 10.9 to 12.6, I2 = 98%] and when the intervention duration was 12 weeks [WMD = 26.6 ng/mL, 95% CI = 9.1 to 44.1, I2 = 0.0%].

The investigators found, in addition, soy intervention resulted in a greater increase in IGF-1 among non-healthy subjects [WMD = 36 ng/mL, 95% CI = 32.7 to 39.4, I2 = 84%] than healthy subjects [WMD = 9.8 ng/mL, 95% CI = 8.9 to 10.7, I2 = 90%].

The investigators concluded ≤40 grams of soy consumption per day during 12 weeks increase the IGF-1 level.

Original title:
The Effect of Soy Intervention on Insulin-Like Growth Factor 1 Levels: A Meta-Analysis of Clinical Trials by Jiawei Zeng J, Feng Y, […], Chen X.

Link:
https://pubmed.ncbi.nlm.nih.gov/32072706/

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Objectives:
Does high magnesium dietary intake reduce risk of type 2 diabetes and stroke?

Study design:
This review article included 53 prospective cohort studies with a total of 1,912,634 participants and 76,678 cases (persons with type 2 diabetes or stroke).

Participants were predominately middle aged at baseline (at the beginning of the studies), with a mean magnesium intake of 370 mg/day for the highest category and 232 mg/day for the lowest category.

The mean duration of all eligible studies was 10.7 years.

Results and conclusions:
The investigators found, when comparing the highest category of magnesium dietary intake (370 mg/day) to the lowest (232 mg/day), a significantly reduced risk of 22% [RR = 0.78, 95% CI = 0.75 to 0.81, p 0.001, I2 = 35.6%, p = 0.021] for type 2 diabetes.

The investigators found, when comparing the highest category of magnesium dietary intake (370 mg/day) to the lowest (232 mg/day), a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.83 to 0.94, p 0.001, I2 = 0%, p = 0.529] for total stroke.

The investigators found, when comparing the highest category of magnesium dietary intake (370 mg/day) to the lowest (232 mg/day), a significantly reduced risk of 12% [RR = 0.88, 95% CI = 0.81 to 0.95, p = 0.001, I2 = 16.9%, p = 0.265] for ischaemic stroke.

The investigators found in studies adjusted for cereal fiber dietary intake, a significantly reduced risk of 21% [RR = 0.79, 95% CI = 0.73 to 0.85, p 0.001] for type 2 diabetes.

The investigators found in studies adjusted for calcium dietary intake, a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.80 to 0.99, p = 0.040] for total stroke.

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 9% [RR = 0.91, 95% CI = 0.83 to 0.99] for total stroke among female.

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.79 to 1.00] for ischaemic stroke among female.

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.82 to 0.96] for total stroke among individuals with BMI ≥25 kg/m².

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 12% [RR = 0.88, 95% CI = 0.81 to 0.96] for ischaemic stroke among individuals with BMI ≥25 kg/m².

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.83 to 0.95] for total stroke among studies wtith ≥12-year follow-up.

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 12% [RR = 0.88, 95% CI = 0.81 to 0.95] for ischaemic stroke among studies wtith ≥12-year follow-up.

The investigators found for every 100 mg/day increment of magnesium dietary intake, a significantly reduced risk of 6% [RR = 0.94, 95% CI = 0.93 to 0.95] for type 2 diabetes.

The investigators found for every 100 mg/day increment of magnesium dietary intake, a significantly reduced risk of 2% [RR = 0.98, 95% CI = 0.97 to 0.99] for total stroke.

The investigators found for every 100 mg/day increment of magnesium dietary intake, a significantly reduced risk of 2% [RR = 0.98, 95% CI = 0.97 to 0.99] for ischaemic stroke.

The investigators concluded magnesium dietary intake has a substantial inverse association with type 2 diabetes and (total/ ischaemic) stroke. Furthermore, female, participants with obesity (BMI ≥ 25 kg/m²) and with a longer follow-up period (≥12 years) obtain greater benefit from magnesium intake with a lower risk of total and ischaemic stroke incidence. Overall, these findings support the guidelines to address the role of magnesium dietary intake in early prevention strategies to combat type 2 diabetes and stroke. However, additional RCTs are needed in the future to validate the causality.

Original title:
Association of magnesium intake with type 2 diabetes and total stroke: an updated systematic review and meta-analysis by Zhao B, Zeng L, [...], Zhang W.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7103847/

Additional information of El Mondo:
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Objectives:
Is there an association between total meat, red meat, processed meat, poultry and fish intake and risk of type 2 diabetes (T2D)?

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

Results and conclusions:
The investigators found when compared with the lowest category, the highest category of total meat intake, significantly increased risk of type 2 diabetes with 33% [summary relative risk = 1.33, 95% CI = 1.16 to 1.52].
Significantly means that there is an association with a 95% confidence.

The investigators found when compared with the lowest category, the highest category of red meat intake, significantly increased risk of type 2 diabetes with 22% [summary relative risk = 1.22, 95% CI = 1.16 to 1.28].
Significantly because summary relative risk of 1 was not found in the 95% CI of 1.16 to 1.28. Summary relative risk of 1 means no risk/association.

The investigators found when compared with the lowest category, the highest category of processed meat intake, significantly increased risk of type 2 diabetes with 25% [summary relative risk = 1.25, 95% CI = 1.13 to 1.37].
Significantly means it can be said with a 95% confidence that the highest category of processed meat intake really increased risk of type 2 diabetes with 25%.

The investigators found no association between highest category of poultry intake and risk of type 2 diabetes [summary relative risk = 1.00, 95% CI = 0.93 to 1.07].
No association because summary relative risk of 1 was found in the 95% CI of 0.93 to 1.07. Summary relative risk of 1 means no risk/association.

The investigators found no association between highest category of fish intake and risk of type 2 diabetes [summary relative risk = 1.01, 95% CI = 0.93 to 1.10].

The investigators found in the dose-response analysis, each additional 100g/day of total and red meat and 50g/day of processed meat, were found to be associated with a 36% [95% CI = 1.23 to 1.49], 31% [95% CI = 1.19 to 1.45] and 46% [95% CI = 1.26 to 1.69] increased risk of type 2 diabetes, respectively.

The investigators found, in addition, there was evidence of a non-linear dose-response association between processed meat and type 2 diabetes [p = 0.004], with the risk increasing by 30% with increasing intakes up to 30g/day.

The investigators concluded 100g/day of total meat, 100g/day red meat and 50g/day of processed meat, increase risk of type 2 diabetes.

Original title:
Meat and fish intake and type 2 diabetes: dose-response meta-analysis of prospective cohort studies by Yang X, Li Y, […], Li L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32302686

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

Objectives:
Omega-3 fatty acid and vitamin E or D co-supplementation may be an important approach to improve metabolic status in gestational diabetes, but the results are conflicting. Therefore, this review article has been conducted.

Do omega-3 fatty acid and vitamin E or D co-supplementation improve metabolic status in gestational diabetes?

Study design:
This review article included 4 RCTs.

Results and conclusions:
The investigators found omega-3 fatty acid and vitamin E or D co-supplementation was associated with a significantly reduced fasting plasma glucose level [MD = -10.47, 95% CI = -15.33 to -5.61, p  0.0001], homeostasis model of assessment-insulin resistance level [MD = -1.6, 95% CI= -2.44 to -0.77, p = 0.0002], malondialdehyde level [MD = -1.00, 95% CI = -1.05 to -0.95, p  0.00001] and triglycerides level [MD = 26.22, 95% CI = -38.94 to -13.51, p  0.0001].

The investigators found omega-3 fatty acid and vitamin E or D co-supplementation was associated with a significantly increased antioxidant capacity level [MD = 173.51, 95% CI = 164.72-182.30, p  0.00001].

The investigators found omega-3 fatty acid and vitamin E or D co-supplementation showed no effect on nitric oxide level [MD = 5.95, 95% CI = -7.48 to 19.37, p = 0.39] or total cholesterol level [MD = 1.63, 95% CI = -13.46 to 16.72, p = 0.83].

The investigators concluded omega-3 fatty acid and vitamin E or D co-supplementation have a favourable effect on metabolic status in gestational diabetes.

Original title:
Influence of omega-3 fatty acid and vitamin co-supplementation on metabolic status in gestational diabetes: A meta-analysis of randomized controlled studies by Li F, Pei L, […], Ye H.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32145487

Additional information of El Mondo:
Find more information/studies on diabetes, pregnancy, omega-3 fatty acid, vitamin D and E right here.

Objectives:
Is there a causal relationship between psyllium (a dietary fiber) consumption and improvements of risk factors of diabetes?

Study design:
This review article included 9 RCTs with 395 participants.

Results and conclusions:
The investigators found psyllium consumption significantly reduced triglycerides levels with 19.18 mg/dL [WMD = -19.18 mg/dL, 95% CI = -31.76 to -6.60, I2 = 98%].

The investigators found psyllium consumption significantly reduced low-density lipoprotein cholesterol levels with 8.96 mg/dL [WMD = -8.96 mg/dL, 95% CI = -13.39 to -4.52, I2 = 97%].

The investigators found psyllium consumption significantly reduced fasting blood sugar levels with 8.96 mg/dL [WMD = -31.71 mg/dL, 95% CI = -50.04 to -13.38, I2 = 97%].

The investigators found psyllium consumption significantly reduced hemoglobin A1c levels with 0.91% [WMD = -0.91%, 95% CI = -1.31 to -0.51, I2 = 99%].

The investigators found no significant change in high-density lipoprotein, body mass index, cholesterol and weight following psyllium consumption.

The investigators concluded there is a significant reduction in triglycerides, low-density lipoprotein cholesterol (bad cholesterol), fasting blood sugar and hemoglobin A1c levels following psyllium consumption among diabetic patients.

Original title:
The effect of psyllium consumption on weight, body mass index, lipid profile, and glucose metabolism in diabetic patients: A systematic review and dose-response meta-analysis of randomized controlled trials by Xiao Z, Chen H, [...], Wei Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31919936

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

Psyllium is a form of fiber made from the husks of the Plantago ovata plant’s seeds. The psyllium husk is a naturally occurring source of soluble fiber.
Psyllium is commonly found in cereals, dietary supplements and is also added to some foods including baked products such as breads, cereal bars and rice/grain cakes.
 

Objectives:
The efficacy of n-3 fatty acids supplementation on the prevention of pregnancy-induced hypertension or preeclampsia remains unclear. Therefore, this meta-analysis (systematic review) has been conducted.

Does n-3 fatty acids supplementation (EPA and/or DHA and/or ALA) decrease risk of pregnancy-induced hypertension and preeclampsia during pregnancy?

Study design:
This review article included 14 RCTs.

Results and conclusions:
The investigators found that n-3 fatty acids supplementation significantly reduced risk of preeclampsia with 18% [RR = 0.82, 95% CI = 0.70 to 0.97, p = 0.024. I2 = 19.0%].
However, n-3 fatty acids supplementation did not associated with a reduced risk of pregnancy-induced hypertension [RR = 0.98, 95% CI = 0.90 to 1.07, p = 0.652, I2 = 0%].

The investigators concluded n-3 fatty acids supplementation (EPA and/or DHA and/or ALA)  reduces risk of preeclampsia during pregnancy.

Original title:
Efficacy of n-3 fatty acids supplementation on the prevention of pregnancy induced-hypertension or preeclampsia: A systematic review and meta-analysis by Bakouei F, Delavar MA, […], Taheri Z.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32039806

Additional information of El Mondo:
Find more information/studies on n-3 fatty acids, hypertension and pregnancy right here.

 

Objectives:
Previous findings on the associations of legume and soy intake with the risk of type 2 diabetes are conflicting. Therefore, this review article (meta-analysis) has been conducted.

Does legume or soy dietary intake reduce risk of type 2 diabetes?

Study design:
This review article included 15 unique cohort studies with a total of 565,810 individuals and 32,093 incident cases (persons with type 2 diabetes).

Overall quality of evidence was rated as moderate for total legumes and low for total soy and soy subtypes.

Results and conclusions:
The investigators found no association between total legumes dietary intake and risk of type 2 diabetes [summary RR = 0.95, 95% CI = 0.79 to 1.14, I2 = 84.8%].
No association because RR of 1 was found in the 95% CI of 0.79 to 1.14. RR of 1 means no risk/association.

The investigators found no association between total soy dietary intake and risk of type 2 diabetes [summary RR = 0.83, 95% CI = 0.68 to 1.01, I2 = 90.8%].

The investigators found no association between soy milk dietary intake and risk of type 2 diabetes [summary RR = 0.89, 95% CI = 0.71 to 1.11, I2 = 91.7%].

The investigators found tofu dietary intake significantly reduced risk of type 2 diabetes with 8% [summary RR = 0.92, 95% CI = 0.84 to 0.99].
Significantly because RR of 1 was not found in the 95% CI of 0.84 to 0.99. RR of 1 means no risk/association.

The investigators found soy protein dietary intake significantly reduced risk of type 2 diabetes with 16% [summary RR = 0.84, 95% CI = 0.75 to 0.95].

The investigators found soy isoflavones dietary intake significantly reduced risk of type 2 diabetes with 12% [summary RR = 0.88, 95% CI = 0.81 to 0.96].

The investigators found in dose-response analysis, significant linear inverse associations for tofu, soy protein and soy isoflavones [all p 0.05].

The investigators concluded dietary intakes of tofu, soy protein and soy isoflavones reduce incident type 2 diabetes. These findings support recommendations to increase intakes of certain soy products for the prevention of type 2 diabetes. However, the overall quality of evidence was low and more high-quality evidence from prospective studies is needed.

Original title:
Legume and soy intake and risk of type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies by Tang J, Wan Y, […], Feng F.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31915830

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

Objectives:
Does dehydroepiandrosterone (DHEA) supplementation improve the outcomes of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) in women with diminished ovarian reserve (DOR) and/or poor ovarian response (POR)?

Study design:
This review article included 9 RCTs, published between 2010 and 2017.
The sample sizes ranged from 24 to 208, with a total of 862 patients.
All of included patients had been diagnosed with diminished ovarian reserve (DOR) and/or poor ovarian response (POR).

The treatment intervention was 75 mg daily DHEA versus placebo.

The lack of significant asymmetry of funnel plot indicated the lack of potential publication bias in the included studies.

Results and conclusions:
The investigators found in a pooled analysis using the random effects model revealed a statistically significant increase in retrieved oocytes in the DHEA group, compared to the control group [MD = 0.91, 95% CI = 0.23 -1.59, p = 0.009, I2  = 53%, p = 0.06].

The investigators found in 8 studies (405 in the DHEA group and 415 in the control group) a statistically significant increase in the clinical pregnancy rate in the DHEA group compared to the control group [RR = 1.27, 95% CI = 1.01 -1.61, p = 0.04, I2 = 0%, p = 0.57].

The investigators found in 5 studies (189 in the DHEA group and 190 in the control group) a statistically significant increase in the live birth rate in the DHEA group, compared to the control group [RR = 1.76, 95% CI = 1.17 -2.63, p = 0.006, I2  = 0%, p = 0.43].

The investigators found in 3 studies (96 in the DHEA group and 99 in the control group) no significant difference in the miscarriage rates between the DHEA and control groups [RR = 0.37, 95% CI = 0.12-1.13, p = 0.08, I2 = 25%, p = 0.26].

The investigators concluded 75 mg daily DHEA supplementation increases the retrieved oocytes, clinical pregnancy rate and live birth rate in women with diminished ovarian reserve and/or poor ovarian response, who are undergoing in vitro fertilization or intracytoplasmic sperm injection.

Original title:
The Effect of Dehydroepiandrosterone (DHEA) Supplementation on IVF or ICSI: A Meta-Analysis of Randomized Controlled Trials by Xu L, Hu C, […], Li Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6620181/

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

Your body naturally produces the hormone dehydroepiandrosterone (DHEA) in the adrenal gland. In turn, DHEA helps produce other hormones, like testosterone and estrogen. Natural dehydroepiandrosterone levels peak in early adulthood and then slowly fall as you age.

 

Objectives:
Free fatty acids, also known as nonesterified fatty acids, are proinflammatory molecules that induce insulin resistance in nonpregnant individuals. Nevertheless, the concentration of these molecules has not been systematically addressed in pregnant women. Therefore, this review article has been conducted.

Do higher plasma levels of free fatty acids increase risk of gestational diabetes mellitus?

Study design:
This review article included 12 case-control studies with a total of 2,426 women, from these, 21% (507/2,426) had a diagnosis of having gestational diabetes.

The mean gestational age at inclusion was 30.3 weeks of gestation.
The mean maternal age was 29 years.
No significant publication bias was found nor a trend towards greater results in small studies.

Results and conclusions:
The investigators found in random-effects model, when compared to controls, women with gestational diabetes had higher levels of free fatty acids [SMD = 0.86, 95% CI = 0.54-1.18, p 0.001, I2 = 91%].
Pooled results showed higher plasma levels of free fatty acid among women with gestational diabetes mellitus during the second trimester of pregnancy [SMD = 1.05 vs. 0.75].

The investigators found meta-regression analysis showed that the gestational age at inclusion was the only cofactor influencing the mean levels of free fatty acids, indicating a trend towards lower plasma levels of free fatty acids later in gestation [estimate = -0.074, 95% CI = -0.143 to -0.004, p = 0.036].

The investigators concluded that plasma levels of free fatty acids are higher in women diagnosed with gestational diabetes mellitus and that this difference is higher during the second trimester of pregnancy. However, more investigation is needed to assess the potential role of free fatty acids in the prediction of gestational diabetes earlier in pregnancy.

Original title:
Plasma Levels of Free Fatty Acids in Women with Gestational Diabetes and Its Intrinsic and Extrinsic Determinants: Systematic Review and Meta-Analysis by Villafan-Bernal JR, Acevedo-Alba M, […], Martinez-Portilla RJ.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6721400/

Additional information of El Mondo:
Find more information/studies on fatty acids and pregnancy right here.
 

Objectives:
The role of zinc in the etiology of type 2 diabetes has been widely reported in recent decades. However, much remains uncertain concerning the effect of zinc on the risk of developing type 2 diabetes. Therefore, this review article has been conducted.

Does zinc reduce risk of type 2 diabetes?

Study design:
This review article included 16 studies.
There was no publication bias.

Results and conclusions:
The investigators found in 7 prospective cohort studies and 1 cross-sectional study (146,027 participants aged between 18 and 84 years and of both genders, belonging to different ethnic groups. Of which, 11,511 type 2 diabetes cases) when comparing the highest versus lowest dietary zinc intakes, a significantly reduced risk of 13% [OR = 0.87, 95% CI = 0.78-0.98, I2 = 64.5%, p = 0.003] for type 2 diabetes.
This relationship was stronger and more evident in rural compared to urban areas [rural areas: OR = 0.59, 95% CI = 0.48-0.73, I2 = 0.0%, p = 0.843 versus urban areas: OR = 0.94, 95% CI = 0.86-1.02, I2 = 43.9%, p = 0.113].

The investigators found no association between supplementary [OR = 0.94, 95% CI = 0.75-1.19, I2 = 85.4%, p = 0.009] or total zinc intake from both diet and supplementation [OR = 0.95, 95% CI = 0.82-1.11, I2 = 56.5%, p = 0.129] and type 2 diabetes risk.

The investigators found in population-based studies that high serum/plasma zinc levels significantly increased risk of type 2 diabetes with 64% [OR = 1.64, 95% CI = 1.25-2.14, I2 > 22.5%, p = 0.275].

The investigators concluded high dietary zinc intake reduces risk of type 2 diabetes. This relationship is stronger and more evident in rural compared to urban areas. However, an elevated serum/plasma zinc concentration is associated with an increased risk of type 2 diabetes in the general population.

Link:
Zinc Intake and Status and Risk of Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis by Fernández-Cao JC, Warthon-Medina M, […], Lowe NM.

Link:
https://www.mdpi.com/2072-6643/11/5/1027/htm

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

Serum/plasma zinc levels can be increased by eating products that contain a lot of zinc and/or taking zinc supplements.
 

Objectives:
Does magnesium reduce risk of type 2 diabetes?

Study design:
This review article included 35 cohort studies and 26 RCTs (1,168 participants).

Results and conclusions:
The investigators found compared to the lowest magnesium dietary intake, the highest level was associated with a 22% lower risk for type 2 diabetes.

The investigators found the risk for type 2 diabetes was reduced by 6% for each 100mg increment in daily magnesium dietary intake.

The investigators found in 26 RCTs (1,168 participants) that magnesium supplementation significantly reduced:
-the fasting plasma glucose (FPG) level [SMD = -0.32, 95% CI = -0.59 to -0.05];
-2-h oral glucose tolerance test (2-h OGTT) result [SMD = -0.30, 95% CI = -0.58 to -0.02];
-fasting insulin level [SMD = -0.17, 95% CI = -0.30 to -0.04];
-homeostatic model assessment-insulin resistance (HOMA-IR) score [SMD = -0.41, 95% CI = -0.71 to -0.11];
-triglyceride (TG) level;
-systolic blood pressure (SBP) and;
-diastolic blood pressure (DBP).

The investigators found trial sequential analysis (TSA) showed an inverse association, with most benefits of magnesium supplementation on glucose metabolism being stable.

The investigators concluded magnesium dietary intake has an inverse dose-response association with type 2 diabetes incidence and supplementation appears to be advisable in terms of glucose parameters in type 2 diabetes/high-risk individuals.

Original title:
Association of Magnesium Consumption with Type 2 Diabetes and Glucose Metabolism: a Systematic Literature Review and Pooled Study with Trial Sequential Analysis by Zhao B, Deng H, [...], Zhang W.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31758631

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

Objectives:
Observational evidence suggests higher nut consumption is associated with better glycemic control. However, it is unclear if this association is causal. Therefore, this review article has been conducted.

Is there a causal relationship between consumption of tree nuts or peanuts and reduced risk of type 2 diabetes?

Study design:
This review article included a total of 40 RCTs with 2,832 unique participants, with a median duration of 3 months (range: 1-12 months).

Results and conclusions:
The investigators found overall consumption of tree nuts or peanuts had a favourable effect on HOMA-IR values [WMD = -0.23, 95% CI = -0.40 to -0.06, I2 = 51.7%] and fasting insulin levels [WMD = -0.40 μIU/mL, 95% CI = -0.73 to -0.07 μIU/mL, I2 = 49.4%].

The investigators found, however, there was no significant effect of nut consumption on fasting blood glucose levels [WMD = -0.52 mg/dL, 95% CI = -1.43 to 0.38 mg/dL, I2 = 53.4%] or HbA1c [WMD = 0.02%, 95% CI = -0.01% to 0.04%, I2 = 51.0%].

The investigators concluded consumption of peanuts or tree nuts decreases HOMA-IR and fasting insulin levels. These findings suggest that nut consumption may improve insulin sensitivity. In the future, well-designed clinical trials are required to elucidate the mechanisms that account for these observed effects.

Original title:
The effect of nuts on markers of glycemic control: a systematic review and meta-analysis of randomized controlled trials by Tindall AM, Johnston EA, […], Petersen KS.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30722007

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

Objectives:
The incidence of type 2 diabetes mellitus (DM) has increased in the US over the last several years. The consumption of low-fat dairy foods has been linked with decreasing the risk of diabetes mellitus but studies have yet to show a clear correlation. Therefore, this review article has been conducted.

Is there a causal relationship between consumption of low-fat dairy foods and reduced risk of type 2 diabetes?

Study design:
This review article included 30 RCTs.
The total sample size was 2,900 with >50% female participants, but the distribution varied greatly across different studies.
The mean age of subjects ranged from 18-63 years.
The funnel plots for all 3 outcomes (HOMA-IR, waist circumference and body weight) did not suggest significant publication bias.

Results and conclusions:
The investigators found (794 individuals) comparing high intake to the control group, consumption of low-fat dairy foods significantly reduced the HOMA-IR values [MD = -1.21, 95% CI = -1.74 to -0.67, p 0.00001, I2 = 92%].

The investigators found (1,348 individuals) comparing high intake to the control group, consumption of low-fat dairy foods significantly reduced waist circumference [MD = -1.09 cm, 95% CI = -1.68 to -0.58, p 0.00001, I2 = 94%].

The investigators found for body weight (2,362 individuals), the low-fat dairy foods intervention group weighed 0.42 kg less than the control group [p 0.00001, I2 = 92%].

The investigators found limiting to studies that were assessed to have low risk of bias did not significantly change the point estimates or heterogeneity statistics (Q or I2) for all 3 outcomes.
Similarly excluding studies with a physical activity component did not significantly alter point estimates or heterogeneity statistics for all 3 outcomes.

The investigators concluded low-fat dairy products have a beneficial effect on HOMA-IR, waist circumference and body weight. This could impact dietary recommendations to reduce type 2 diabetes risk.

Original title:
The Effects of Dairy Intake on Insulin Resistance: A Systematic Review and Meta-Analysis of Randomized Clinical Trials by Sochol KM, Johns TS, […], Melamed ML.

Link:
https://www.mdpi.com/2072-6643/11/9/2237/htm

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