Whey Protein Supplementation Improves Body Composition and Cardiovascular Risk Factors in Overweight and Obese Patients: A Systematic Review and Meta-Analysis

BACKGROUND: Previous literature shows possible benefits of whey protein supplementation in promoting weight loss. However, most studies do not have enough power to show beneficial effects on body composition and cardiovascular disease (CVD) risk factors. This meta-analysis evaluated effects of whey protein in individuals who are overweight and obese. METHODS: We comprehensively searched the databases of MEDLINE, Embase, and Cochrane databases. The inclusion criteria were published randomized control trials (RCTs) comparing whey protein supplementation to placebo or controls in individuals who are overweight or obese. The primary outcome was the differences in the change in body composition (body weight, waist circumference, total fat mass, body lean mass). We also examined the changes in CVD risk factors as secondary outcomes. We calculated pooled mean difference (MD) with 95% confidence intervals (CIs) using a random effects model. RESULTS: Nine RCTs were included in the meta-analysis. There was a significant reduction of body weight (MD = 0.56, 95% CI: 0.30-0.81), lean mass (MD = 0.77, 95% CI: 0.59-0.96), and fat mass (MD = 1.12, 95% CI: 0.77-1.47) favoring the whey protein group. There were improvements in multiple CVD risk factors including levels of systolic blood pressure, diastolic blood pressure, glucose, high-density lipoprotein, and total cholesterol (all p values <0.05). CONCLUSIONS: Whey protein supplementation seems to improve body weight, total fat mass, and some CVD risk factors in overweight and obese patients. Further studies regarding optimal dosage and duration of whey protein supplementation would be helpful to assess potential favorable effects in individuals who are overweight or obese.