Adults with prediabetes assigned to zinc supplementation are less likely to progress to type 2 diabetes compared with adults not assigned to supplementation, and supplementation may lead to reductions in fasting plasma glucose, 2-hour oral glucose tolerance test and insulin resistance, according to researchers in Sri Lanka.
Priyanga Ranasinghe, MBBS, of the department of pharmacology, faculty of medicine at the University of Colombo in Sri Lanka, and colleagues evaluated data from 200 adults (mean age, 51.8 years; 43% men) with prediabetes randomly assigned to zinc 20 mg per day or placebo to determine the effect of zinc on glycemic control, other cardiometabolic and anthropometric parameters, and progression of disease.
Participants were enrolled between August 2012 and December 2016; the study duration was 12 months. Study visits were conducted at baseline, 1, 3, 6 and 12 months.
Type 2 diabetes developed in more participants in the placebo group compared with the zinc group (25% vs. 11%; OR = 2.7; 95% CI, 1.2-6.5). Reductions in FPG and 2-hour OGTT were observed in the zinc group but not in the placebo group. From baseline, insulin resistance decreased significantly at 6 and 12 months in the zinc group, but the decreases were not observed in the placebo group.
Significant reductions were observed in both groups for systolic and diastolic blood pressure. There were no significant changes in BMI, waist circumference, HDL cholesterol or triglycerides. Significant reductions in total cholesterol and LDL cholesterol were observed in the zinc group, whereas the levels remained unchanged or increased in the placebo group.
“Zinc deficiency was observed in the present study population with prediabetes, which was corrected by supplementation,” the researchers wrote. “Zinc supplementation reduced blood glucose and insulin resistance, while improving beta-cell function. Furthermore, disease progression to diabetes was reduced, and beneficial effects of supplementation were also noted on total and LDL cholesterol. However, these results need to be replicated in larger randomized controlled trials, prior to advocating the use of zinc supplementation for prevention of diabetes and further studies are also required to full elucidate the mechanisms responsible.” – by Amber Cox
Disclosures: The authors report no relevant financial disclosures.