Boys are more likely to have asthma than girls, but that flips after puberty. Researchers suspect that sex hormones are a factor. Westend61/Getty Images hide caption toggle caption Westend61/Getty Images Shots - Health News Testosterone May Help Protect Men From Asthma November 28, 2017 Women are more likely to have asthma than men. One possible reason? Testosterone could block a protein that helps spark an asthma attack, a study finds, while estrogen may not.