The effect of a high-protein, low glycemic–load diet versus a conventional, high glycemic–load diet on biochemical parameters associated with acne vulgaris: A randomized, investigator-masked, controlled trial

BackgroundNo previous study has sought to examine the influence of dietary composition on acne vulgaris.ObjectiveWe sought to compare the effect of an experimental low glycemic–load diet with a conventional high glycemic–load diet on clinical and endocrine aspects of acne vulgaris.MethodsA total of 43 male patients with acne completed a 12-week, parallel, dietary intervention study with investigator-masked dermatology assessments. Primary outcomes measures were changes in lesion counts, sex hormone binding globulin, free androgen index, insulin-like growth factor-I, and insulin-like growth factor binding proteins.ResultsAt 12 weeks, total lesion counts had decreased more in the experimental group (−21.9 [95% confidence interval, −26.8 to −19.0]) compared with the control group (−13.8 [−19.1 to −8.5], P = .01). The experimental diet also reduced weight (P = .001), reduced the free androgen index (P = .04), and increased insulin-like growth factor binding protein-1 (P = .001) when compared with a high glycemic–load diet.LimitationsWe could not preclude the role of weight loss in the overall treatment effect.ConclusionThis suggests nutrition-related lifestyle factors play a role in acne pathogenesis. However, these preliminary findings should be confirmed by similar studies.