No scientific basis for aphrodisiacs actually working has been identified. There may be some placebo effect. (Pease, Barbara and Allan. Why Men Don’t Have a Clue and Women Always Need More Shoes. p 217-218. NY: Broadway Books, 2004.)

Several substances have been tried for supposedly aphrodisiac qualities (e.g., bananas, oysters, sex organs of animals). Eating bulls/ testicles doesn’t work; enzymes in the stomach break down the testosterone before it can reach the blood stream. (Durden-Smith, Jo, and Diane deSimone. Sex and the Brain. p 255-260. NY:Arbor House Publishing, 1983.)