New evidence suggests that low serum Vitamin D may cause nonalcoholic fatty liver disease (NAFLD). Hypovitaminosis D is associated with the severity and incidence of NAFLD. The objective of this study was to conduct a systematic review on randomized controlled trials (RCTs) assessing the effect of Vitamin D on serum metabolic profile among NAFLD patients. Databases including PubMed, Institute for Scientific Information Web of Science, Scopus, and Google Scholar were searched up to November 2016. RCTs which studied Vitamin D effect on metabolic profiles and liver function, and conducted among adults were included. Six articles were eligible to be considered in this systematic review. According to the result, Vitamin D supplementation might improve lipid profile and inflammatory mediators when compared with placebo. No article indicated significant effect of Vitamin D on liver enzymes except one article which revealed that Vitamin D together with calcium carbonate can reduce liver enzymes. Vitamin D supplementation may not improve anthropometric measures and glycemic index variables among patients with NAFLD. Vitamin D supplement might improve NAFLD symptoms, especially inflammatory mediators. More RCTs in different parts of world with different forms and doses of Vitamin D are necessary.

Metabolic syndrome (MetS), a series of symptoms, including abdominal obesity, impaired glucose tolerance and insulin metabolism, hypertension, and dyslipidemia, is considered as the risk of developing cardiovascular disease and diabetes that can predispose a pregnant women to serious health problem, women in the developed as well as the developing countries. This study was aimed to investigate the effects of appropriate interventions on pregnant women with indicators of MetS to further improve the outcome of pregnancy. This systematic review was performed to extract articles of randomized controlled trials (RCT) on pregnant women with indicators of ( MetS) and focusing on physical activity, dietary or lifestyle interventions on maternal health or perinatal outcomes, with searching in the Web of Science, PubMed, CDSR, Scopus, and Google Scholar were investigated. Two researchers independently evaluated the quality of the studies, being presented in all the articles and ranked the studies as high/low quality; the level of evidence was based on the number of high-quality studies and the coordination of the obtained results. Then, 17 articles, which met the inclusion criteria, were selected; among these, 7 articles studied the physical activity, 3 articles reviewed diets, 6 probed the lifestyle interventions, and 1 article was on counseling. In general, evidence suggested how the physical activity and proper diet impacts on proper weight gain during pregnancy, prevents maternal complications, and improves the outcome of pregnancy. According to the results of this systematic review, proper interventions during pregnancy can have a positive effect on maternal weight gain and the general health condition of pregnant women with indicators of MetS.