Change of some oxidative stress parameters after supplementation with whey protein isolate in patients with type 2 diabetes.

OBJECTIVES

The aim of this study was to evaluate the effects of undenatured whey protein isolate (WPI; ≥92.5%) with a high content of native cysteine (2.7%) and a standardized content of lactoferrin (≥0.7%) on parameters related to oxidative stress and inflammation in individuals with type 2 diabetes mellitus.

METHODS

We assigned 120 white patients with type 2 diabetes and glycated hemoglobin ≥6.5% to two groups. The patients were supplemented daily with WPI or placebo for 3 mo. After 3 mo, the markers of oxidation (superoxide dismutase, glutathione peroxidase, glutathione, and reduced glutathione-to-oxidized glutathione ratio) and inflammation (high sensitivity C-reactive protein, interleukin-6, tumor necrosis factor -α, malondialdehyde) were significantly lower in the WPI group than in the placebo group (P < 0.05). The WPI group obtained a significant improvement in the lipid profile and a reduction in fasting plasma glucose compared with baseline and placebo (P < 0.05). No variations of body weight, body mass index or circumferences and metalloproteinase-2 and -9, or soluble receptor for advanced glycation end product were recorded in either groups.

CONCLUSION

Supplementation with WPI may be useful in patients with diabetes to control fasting glycemia. Moreover, it can help to improve inflammatory and oxidative stress, which play a crucial role in the development of diabetes complications and also in the progression of other chronic diseases.