It’s also a good idea to check if the supplement contains any ingredients you might be allergic to. And, of course, if you have any health condition or are on medication, please consult with your doctor first before taking any testosterone boosters. In short, natural Ketosium XS Keto Reviews boosters work on the symptoms of low testosterone. In particular, they sometimes develop gynecomastia, or enlarged breast tissue. This effect is believed to occur due to an imbalance between testosterone and estrogen within men. Testosterone plays a role in several body functions, including hair production.