Do testosterone boosters work?
There is no responsible one-word answer for an entire product category. Products use different ingredients, doses and claims, while studies examine different populations and outcomes.
Ask what “work” means
A change in a laboratory marker, a subjective outcome and a clinically meaningful improvement are different endpoints. Evidence for one does not automatically establish the others.
Match evidence to the claim
FTC guidance emphasizes that health-product claims should have competent and reliable scientific evidence relevant to the claim. Evaluate each finished product and claim rather than assuming the category works as a whole.