Skeptics have dismissed the purported aphrodisiac benefits of eating oysters as purely psychological, based on their suggestive shape and slippery texture. But Gloria Tsang, a Vancouver registered dietitian, says there may be something to the belief. “A lot of shellfish—including oysters, clams, crabs, lobsters and mussels—are high in zinc, which can trigger a surge in the production of sex hormones.”
Tsang adds that these bivalve mollusks also contain two rare amino acids: D-aspartic acid and N-methyl-D-aspartate. Joint American-Italian research in 2005 at Barry University in Miami and the Laboratory of Neurobiology in Naples, Italy, found that giving these amino acids to rats increased testosterone in the males and progesterone in the females—both are hormones associated with greater sexual activity.