RESUMO
BACKGROUND: Acne vulgaris (AV) exacerbation after whey protein (WP) consumption remains inconclusive among experts. OBJECTIVES: To investigate the association between WP consumption and acne severity in men with acne. METHODS: A noninferiority trial was conducted in men with mild to moderate facial and/or truncal acne. After randomization, participants in an intervention group took daily WP 30 g with a non-WP nutritional supplement 18 g (WP group, n = 25), while the control group took a non-WP nutritional supplement 46 g (non-WP group, n = 24). At each follow-up appointment, investigators evaluated acne count (total acne lesions, comedonal lesions, and inflammatory lesions) and severity. RESULTS: Forty-nine participants had a mean age of 19.7 years (standard deviation [SD], 0.9) and 20.3 years (SD, 1.4) in the WP and non-WP groups, respectively. The mean differences in the facial and truncal total acne lesions for the WP and non-WP group were -5.99 (95% confidence interval [CI], -13.18 to 1.19, p = 0.09) and -2.18 (95% CI, -11.83 to 7.48, p = 0.65), respectively. For severity changes, only one (4.3%) participant in the non-WP group reported an increase in the Investigator Global Assessment scale of at least two levels. CONCLUSIONS: In this 6-month trial, men with acne who undertook WP supplementation showed a noninferior difference in the changes in total acne lesions and severity of facial and truncal acne compared with the non-WP group.