摘要
The original study by Alessio et al reported that skinny people (SP) serum canpromote the formation of brown adipocytes, but not the differentiation of whiteadipocytes. This finding may explain why SP do not often become obese, despiteconsuming more calories than the body needs. More importantly, theydemonstrated that circulating factors in SP serum can promote the expression ofUCP-1 protein, thereby reducing fat accumulation. In this study, only male serumsamples were evaluated to avoid the interference of sex hormones in experiments,but adult males also synthesize estrogen, which is produced by the cells of thetestes. At the same time, adult females secrete androgens, and females synthesizeandrogens that are mainly produced by the adrenal cortex. We believe that theapproach of excluding sex hormone interference by sex selection alone may beflawed, so we comment on the article and debate the statistical analysis of thearticle.