Conclusions
Whey protein supplementation in overweight women increased nesfatin concentrations and could promote increase of resting metabolic rate as part of body composition improvement programs compared to collagen supplementation for 8 weeks. Additionally, our findings suggest that collagen may not be an effective supplement for overweight women who are attempting to alter body composition.
Methods
In this randomized double-blind study, 37 women, [mean ± SE, age 40.6 ± 1.7 year; BMI (kg/m2) 30.9 ± 0.6], consumed sachets containing 40 g/day of concentrated whey protein (25 g total protein, 2.4 leucine, 1.0 valine, 1.5 isoleucine, n = 17) or 38 g/day of hydrolysed collagen (26 g total protein, 1.02 leucine, 0.91 valine, 0.53 isoleucine, n = 20) in the afternoon snack. The compliance was set at >70% of the total theoretical doses. The dietary intake was evaluated by a 6-day food record questionnaire. At the beginning and after eight weeks of follow-up, body composition was evaluated by using dual-energy X-ray absorptiometry and lipid profile, insulin resistance, C-reactive protein, adiponectin, leptin and nesfastin plasma concentrations were analyzed.
Results
Supplements were isocaloric and isoproteic. There were no differences in caloric intake (p = 0.103), protein (p = 0.085), carbohydrate (p = 0.797) and lipids (p = 0.109) intakes. The branched chain amino acids (BCAA) (GC: 1.8 ± 0.1 g vs. WG: 5.5 ± 0.3 g, p < 0.001) and leucine intake (CG: 0.1 ± 0.1 g vs. WG: 2.6 ± 0.1 g, p < 0.001) were higher in WG compared to CG. BMI increased in the CG (0.2 ± 1.1 kg/m2, p = 0.044) but did not change in WG. WG decreased the android fat (-0.1 ± 0.3 kg, p = 0.031) and increased nesfatin concentrations (4.9 ± 3.2 ng/mL, p = 0.014) compared to CG. Conclusions: Whey protein supplementation in overweight women increased nesfatin concentrations and could promote increase of resting metabolic rate as part of body composition improvement programs compared to collagen supplementation for 8 weeks. Additionally, our findings suggest that collagen may not be an effective supplement for overweight women who are attempting to alter body composition.