The final supplement category we will consider here are testosterone boosters – herbal products promoted to increase testosterone levels and in doing so improve wellbeing, sexual potency and body composition.
Much like Nootropics this is a huge category with numerous different available products, but the overall message is that non-drug testosterone boosting supplements may increase your total, free or bound testosterone (around 95-99% of testosterone in your blood is bound to proteins to render it inert) by less than 10%. Even the lowest dose of injectable steroids typically used will increase testosterone by over 200-300%, and therefore it should be self-evident that testosterone boosters are unlikely to increase muscle mass or meaningfully reduce bodyfat levels (two effects of supraphysiological testosterone levels).
With that said, maca, tribulus terrestris and fenugreek supplementation can increase feelings of wellbeing and libido, which are two things often sought from testosterone boosters, and so these could be considered, even though they do not actually affect hormone levels.