Nutrition and health

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

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

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:
There are numerous trials reported the effect of alpha-lipoic acid (ALA) on obesity measurements; while no summarised dose-response meta-analysis is available to address the effects of dose and duration of ALA supplementation on obesity measurements. Therefore, this review article has been conducted.

Does alpha-lipoic acid supplementation improve obesity measurements including weight, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and fat mass (FM)?

Study design:
This review article included 18, 21 and 8 RCTs of ALA-weight, ALA-BMI, ALA-WC, respectively.

Results and conclusions:
The investigators found in two-class meta-analysis, alpha-lipoic acid supplementation significantly reduced weight [WMD = -2.29 kg, 95% CI = -2.98 to -1.60, p 0.01] and BMI [WMD = -0.49 g/m², 95% CI = -0.83 to -0.15, p = 0.005] but had no effect on waist circumference [WMD = -2.57 cm, 95% CI = -8.91 to 3.76, p = 0.426].

The investigators found while the dose-response meta-analysis revealed that the duration of alpha-lipoic acid supplementation was a significant factor affecting waist circumference reduction [p non-linearity = 0.047].
While no evidence of departure from linearity was observed for other variables; moreover, subgrouping also revealed that gender could be an important factor affecting the alpha-lipoic acid impact on waist circumference, which was significant among women [WMD = -4.099, 95%CI = -7.837 to -0.361, p = 0.032].

The investigators concluded that alpha-lipoic acid supplementation reduces BMI, weight in a two-class meta-analysis without evidence of departure from linearity in terms of dose or duration. While the association of alpha-lipoic acid supplementation on waist circumference is dependent to the duration of the study. Although further trials evaluating the other obesity measurements specially central obesity will be helpful to infer a more reliable result.

Original title:
Alpha-lipoic acid supplementation significantly reduces the risk of obesity in an updated systematic review and dose response meta-analysis of randomised placebo-controlled clinical trials by Vajdi M and Farhangi MA.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32091656

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

Objectives:
Does coenzyme Q10 supplementation reduce body weight and body mass index (BMI) of patients in randomized controlled clinical trial studies (RCTs)?

Study design:
This review article included 17 RCTs.

Results and conclusions:
The investigators found results of random-effect size meta-analysis showed that supplementation with coenzyme Q10 had no significant decreasing effects on body weight [WMD = 0.28 kg, 95% CI = -0.91 to 1.47, p = 0.64] and BMI [WMD = -0.03, 95% CI = -0.4 to 0.34, p = 0.86] of study participants.
No significant because the calculated p-value of 0.64 was larger than the p-value of 0.05.
Subgroup analysis revealed that dosage of Q10 and trial duration could not differ the results of Q10 supplementation.

The investigators concluded that coenzyme Q10 supplementation has no decreasing effects on body weight and BMI.

Original title:
Effect of Q10 supplementation on body weight and body mass index: A systematic review and meta-analysis of randomized controlled clinical trials by Saboori S, Rad EY, […], Falahi E.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31336462

Additional information of El Mondo:
Find more information/studies on RCTs/subgroup analysis, coenzyme Q10 and obesity/overweight 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:
Find more information/studies food fortification and iron right here.

Objectives:
Results regarding the association between fish intake and risk of metabolic syndrome (MetS) are ambiguous. Therefore, this review article has been conducted.

Does fish consumption reduce risk of metabolic syndrome?

Study design:
This review article included 10 cross-sectional studies and 6 cohort studies.

Results and conclusions:
The investigators found fish consumption significantly reduced risk of metabolic syndrome with 20% [OR = 0.80, 95% CI = 0.66 to 0.96, p = 0.017, I2 = 62.9%] in cohort studies.
However, this reduced risk was not significant in cross-sectional studies [OR = 0.80, 95% CI = 0.70 to 1.02, p = 0.085, I2 = 50.1%].
Significantly because OR of 1 was not found in the 95% CI of 0.6 to 0.96. OR of 1 means no risk/association.

The investigators found a significant non-linear association between fish intake levels and risk of metabolic syndrome [p for non-linearity = 0.010].

The investigators concluded that fish consumption reduces risk of metabolic syndrome when combining data from prospective cohort studies. Further studies are needed to confirm such an effect.

Original title:
A systematic review and meta-analysis of the association between fish consumption and risk of metabolic syndrome by Karimi G, Heidari Z, [...], Haghighatdoost F.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32127332

Additional information of El Mondo:
Find more information/studies on fish consumption and obesity/overweight 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:
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:
Genistein (4',5,7-trihydroxyisoflavone) is a phytoestrogen with potential health benefits in the prevention of cardiovascular disease. However, the evidence regarding its effects on hypertension has not been conclusive. Therefore, this review article has been conducted.

Do genistein supplements reduce blood pressure?

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

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

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

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

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

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

Additional information of El Mondo:
Find more information/studies on genistein and overweight 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:
The relationship between serum copper (Cu) level and overweight/obesity remains controversial. Therefore, this review article (meta-analysis) has been conducted.

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

Study design:
This review article included 21 articles.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Study design:
This review article included 5 RCTs.

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

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

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

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

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

Objectives:
Maternal folic acid supplementation is considered mandatory in almost every country in the world to prevent congenital malformations. However, little is known about the association of maternal folic acid intake with the occurrence of childhood cancer. Therefore, this review article has been conducted.

Does maternal folic acid supplementation during pregnancy reduce risk of childhood cancer?

Study design:
This review article included 17 case-control studies.

Results and conclusions:
The investigators found in random-effects model, maternal folic acid supplementation during pregnancy significantly reduced risk of childhood acute lymphoblastic leukaemia with 25% [OR = 0.75, 95% CI = 0.66 to 0.86].
Significantly because OR of 1 was not found in the 95% CI of 0.66 to 0.86. OR of 1 means no risk/association.

The investigators found in random-effects model, there was no significant association between maternal folic acid supplementation during pregnancy and acute myeloid leukaemia [OR = 0.70, 95% CI = 0.46 to 1.06] or childhood brain tumours [OR = 1.02, 95% CI = 0.88 to 1.19].
No significant because OR of 1 was found in the 95% CI of 0.88 to 1.19. OR of 1 means no risk/association.

The investigators concluded maternal folic acid supplementation during pregnancy reduces risk of childhood acute lymphoblastic leukaemia. Thus, healthcare professionals are recommended to provide regular health education and health promotion to the community on the benefits of folic acid supplementation during pregnancy.

Original title:
The Protective Effect of Maternal Folic Acid Supplementation on Childhood Cancer: A Systematic Review and Meta-analysis of Case-control Studies by Wan Ismail WR, Abdul Rahman R, […],Nawi AM.

Link:
https://www.jpmph.org/journal/view.php?doi=10.3961/jpmph.19.020

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

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

Does L-carnitine supplementation reduce blood pressure?

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

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

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

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

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

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

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

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

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

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

Does dietary calcium intake reduce risk of metabolic syndrome?

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

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

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

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

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

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

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

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

Objectives:
Does calcium supplement with or without other drugs reduce risk of preeclampsia and gestational hypertension?

Study design:
This review article included 27 RCTs, with 28,492 pregnant women.

Results and conclusions:
The investigators found calcium supplement significantly reduced risk of preeclampsia with 49% [RR = 0.51, 95% CI = 0.40 to 0.64].

The investigators found calcium supplement significantly reduced risk of gestational hypertension with 30% [RR = 0.70, 95% CI = 0.60 to 0.82].

The investigators found sub-analyses revealed high-dose (1.2-2 g/day), moderate-dose (0.6-1.2 g/day) and low-dose (0.6 g/day) of calcium supplement significantly reduced risk of preeclampsia.

The investigators found sub-analyses revealed high-dose (1.2-2 g/day) and moderate-dose (0.6-1.2 g/day) of calcium supplement significantly reduced risk of gestational hypertension.

The investigators concluded high-dose (1.2-2 g/day) and moderate-dose (0.6-1.2 g/day) of calcium supplement reduced both risk of preeclampsia and gestational hypertension. However, further studies with direct comparison of different dose of calcium supplementation are needed to explore the ideal dose of calcium supplementation to prevent preeclampsia and gestational hypertension.

Original title:
The association between calcium supplement and preeclampsia and gestational hypertension: a systematic review and meta-analysis of randomized trials by Sun X, Li H, [...], Zhang X.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30935246

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

 

Objectives:
The role of chromium as a weight loss agent remains questionable and although previous meta-analyses findings have reported small reductions in body weight in individuals with overweight/obesity following chromium supplementation, there have been significant limitations with these findings. Therefore, this review article has been conducted.

Do individuals with overweight/obesity benefit from chromium supplementation?

Study design:
This review article included 21 RCTs with a total of 1,316 participants.

Results and conclusions:
The investigators found pooled analysis showed significant reductions in anthropometric indices associated with body composition for:
-weight loss [WMD = -0.75 kg, 95% CI = -1.04 to -0.45, p  0.001];
-body mass index (BMI) [WMD = -0.40, 95% CI = -0.66 to -0.13, p = 0.003] and;
-body fat percentage [WMD = -0.68%, 95% CI = -1.32 to -0.03, p = 0.04] in individuals with overweight/obesity following chromium supplementation. No changes were detected in controls.

The investigators found subgroup analysis showed significant improvements in weight loss and body fat percentage, particularly for study durations ≤12 weeks and doses ≤400 μg/d chromium.

The investigators concluded ≤400 μg/d chromium supplementation during ≤12 weeks is associated with some improvements in body composition in subjects with obesity/overweight. The effect size was medium and the clinical relevance of chromium as a weight loss aid remains uncertain. Therefore, further investigation from larger and well-designed randomized controlled studies, especially in patients with diabetes, is warranted.

Original title:
A meta-analysis of the effect of chromium supplementation on anthropometric indices of subjects with overweight or obesity by Tsang C, Taghizadeh M, […], Jafarnejad S.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31115179

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Objectives:
The threshold for population-level optimal red blood cell (RBC) folate concentration among women of reproductive age for the prevention of neural tube defects has been estimated at 906 nmol/L. However, the dose-response relationship between folic acid intake and blood folate concentrations is uncharacterized. Therefore, this review article has been conducted.

Is there dose-response relationship between folic acid intake and blood folate concentrations?

Study design:
This review article included 23 articles for red blood cell folate and by 97 articles for serum/plasma folate.

Results and conclusions:
The investigators found in 17 studies red blood cell (RBC) folate concentration increased 1.78 fold [95% CI = 1.66 to 1.93] from baseline to steady-state at 375-570 µg folic acid/day and it took a median of 36 weeks of folic acid intake [95% CI = 27 to 52] to achieve steady-state red blood cell folate concentrations.

The investigators found for every 100 µg/day folic acid intake, serum/plasma folate concentrations increased 11.6% [95% CI = 8.4 to 14.9] from baseline to steady-state, over a median of 13 weeks [95% CI = 10 to 16].

The investigators concluded that there is a dose-response relationship between folic acid intake and changes in blood folate concentrations. At 375-570 µg folic acid/day, red blood cell folate concentrations increase 1.78 fold from baseline to steady-state, over a median of 36 weeks. For every 100 µg/day folic acid intake, serum/plasma folate concentrations increase 11.6% from baseline to steady-state, over a median of 13 weeks. These results can inform how much additional folic acid intake is needed among populations of women whose red blood cell folate concentrations are below the optimal threshold.

Original title:
Systematic Review and Bayesian Meta-analysis of the Dose-response Relationship between Folic Acid Intake and Changes in Blood Folate Concentrations by Crider KS, Devine O, […], Berry RJ.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6356991/

Additional information of El Mondo:
Find here more information/studies about pregnancy and folaat (also called folic acid).
 

Objectives:
Diverse studies have investigated the impact of prenatal exposure to vitamin D levels on brain development. However, evidence in humans has never been systematically reviewed. Therefore, this meta-analysis (systematic review) has been conducted.

Has a high prenatal vitamin D level positive effect on brain development of the born child?

Study design:
This review article included 25 studies.

Results and conclusions:
The investigators found comparing with the lowest category of prenatal 25(OH)D levels (vitamin D level in blood), the highest prenatal 25(OH)D levels had no significant effects on cognition [pooled beta coefficients = 0.95, 95% CI = -0.03 to 1.93, p = 0.05].

The investigators found comparing with the lowest category of prenatal 25(OH)D levels (vitamin D level in blood), the highest prenatal 25(OH)D levels had no significant effects on psychomotor development [pooled beta coefficients = 0.88, 95% CI = -0.18 to 1.93, p = 0.10].

The investigators found comparing with the lowest category of prenatal 25(OH)D levels (vitamin D level in blood), the highest prenatal 25(OH)D levels significantly reduced risk of ADHD of the born child with 28% [pooled relative risk = 0.72, 95% CI = 0.59 to  0.89, p = 0.002].

The investigators found comparing with the lowest category of prenatal 25(OH)D levels (vitamin D level in blood), the highest prenatal 25(OH)D levels significantly reduced risk of autism-related traits of the born child with 58% [pooled odds ratio = 0.42, 95% CI = 0.25 to 0.71, p = 0.001].

The investigators found there was little evidence for protective effects of high prenatal 25(OH)D for language development and behaviour difficulties of the born child.

The investigators concluded this meta-analysis provides supporting evidence that increased prenatal exposure to 25(OH)D levels is associated with reduced risk of ADHD and autism-related traits of the born child later in life. Associations represent a potentially high public health burden given the current prevalence of vitamin D deficiency and insufficiency among childbearing aging and pregnant women.

Original title:
Neurodevelopmental effects of prenatal vitamin D in humans: systematic review and meta-analysis by García-Serna AM and Morales E.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30696940

Additional information of El Mondo:
Find more information/studies on vitamin D and pregnancy 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:
Probiotic supplementation in early life may be effective in preventing atopic dermatitis (AD); however, results regarding efficacy have been controversial. Therefore, this meta-analysis (systematic review) has been conducted.

Does probiotic supplementation in early life prevent atopic dermatitis in infants and children?

Study design:
This review article included 28 RCTs.

Results and conclusions:
The investigators found compared with controls, probiotic supplementation of mother was associated with a significantly reduced risk of 31% for atopic dermatitis in infants and children [OR = 0.69, 95% CI = 0.58-0.82, p  0.0001].

The investigators found compared with controls, the use of probiotics of mother during both the prenatal and the postnatal period significantly reduced the incidence of atopic dermatitis in infants and children with 33% [OR = 0.67, 95% CI = 0.54-0.82].
However, analysis of studies of probiotics given prenatally only or postnatally only did not reach statistical significance.

The investigators concluded that probiotic supplementation of mother during both the prenatal and the postnatal period reduces the incidence of atopic dermatitis in infants and children. These findings suggest that starting probiotic treatment during gestation and continuing through the first 6 months of the infant's life may be of benefit in the prevention of atopic dermatitis.

Original title:
Probiotic Supplementation for Prevention of Atopic Dermatitis in Infants and Children: A Systematic Review and Meta-analysis by Li L, Han Z, […], He C.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30465329

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

Objectives:
Inositol (ISL) embraces a family of simple carbohydrates with insulin-sensitizing properties, whose most common isoforms are Myo-inositol (MYO) and D-chiro inositol (DCI). Therefore, this meta-analysis (systematic review) has been conducted.

Does inositol supplementation reduce gestational diabetes (GDM)?

Study design:
This review article included 5 RCTs with a total of  965 participants.
The primary outcome was the preventive effect on gestational diabetes, defined as the rate of gestational diabetes in women without a prior diagnosis of gestational diabetes.
Pooled results were expressed as odds ratio (OR) with a 95% confidence interval (95% CI).
No adverse effects were reported for inositol supplementation.

Results and conclusions:
The investigators found inositol supplementation significantly reduced risk of gestational diabetes with 51% [OR = 0.49, p = 0.01]. However, this reduced risk was only significant in patients receiving 2g inositol twice daily.

The investigators found inositol supplementation significantly reduced risk of preterm delivery with 65% [OR = 0.35, 95% CI = 0.17-0.74, p = 0.006]. However, this reduced risk was only significant in patients receiving 2g inositol twice daily.

The investigators concluded double administration of inositol 2g per day reduces gestational diabetes rate and preterm delivery rate. Therefore, inositol supplementation may represent a novel strategy for gestational diabetes prevention.

Original title:
Inositol for the prevention of gestational diabetes: a systematic review and meta-analysis of randomized controlled trials by Vitagliano A, Saccone G, […], Berghella V.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30564926

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