Testosterone is an essential hormone for both men and women, but its role is more significant in men, who have higher levels. It contributes to male sexual health and development, fertility, muscle growth, fat loss, and other aspects of health. Testosterone levels fall in men as they age. There’s also concern about an overall drop in testosterone levels in the United States. Lifestyle habits and health factors appear to play a role. Tribulus Terrestris, Magnesium and Zinc are the staple to any good natural test booster. In Ultra Test those ingredients top the list.