Testosterone deficiency aggravates the MetS in men by bringing forward obesity and hyperinsulinemia, which in turn suppresses testicular androgen production («vicious cycle»)(also discussed in II.G).
The investigators wrote, «After 14 d on this [0 % carbohydrate, 11 % protein, and 89 % fat] diet, 3 h of hyperinsulinemia were not sufficient to suppress fat oxidation and increase glucose oxidation.