Effect of whey supplementation on circulating C-reactive protein: a meta-analysis of randomized controlled trials

Nutrients. 2015 Feb 9;7(2):1131-43. doi: 10.3390/nu7021131.


Whey supplementation is beneficial for human health, possibly by reducing the circulating C-reactive protein (CRP) level, a sensitive marker of inflammation. Thus, a meta-analysis of randomized controlled trials was conducted to evaluate their relationship. A systematic literature search was conducted in July, 2014, to identify eligible studies. Either a fixed-effects model or a random-effects model was used to calculate pooled effects. The meta-analysis results of nine trials showed a slight, but no significant, reduction of 0.42 mg/L (95% CI -0.96, 0.13) in CRP level with the supplementation of whey protein and its derivates. Relatively high heterogeneity across studies was observed. Subgroup analyses showed that whey significantly lowered CRP by 0.72 mg/L (95% CI -0.97, -0.47) among trials with a daily whey dose≥20 g/day and by 0.67 mg/L (95% CI -1.21, -0.14) among trials with baseline CRP≥3 mg/L. Meta-regression analysis revealed that the baseline CRP level was a potential effect modifier of whey supplementation in reducing CRP. In conclusion, our meta-analysis did not find sufficient evidence that whey and its derivates elicited a beneficial effect in reducing circulating CRP. However, they may significantly reduce CRP among participants with highly supplemental doses or increased baseline CRP levels.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adult
  • Biomarkers / blood
  • C-Reactive Protein / analysis*
  • Dietary Supplements*
  • Female
  • Humans
  • Inflammation / diet therapy
  • Male
  • Milk Proteins / administration & dosage*
  • Milk Proteins / pharmacology
  • Randomized Controlled Trials as Topic
  • Whey Proteins
  • Young Adult


  • Biomarkers
  • Milk Proteins
  • Whey Proteins
  • C-Reactive Protein