When February comes around each year, the media capitalizes on Valentine's Day with articles on romantic gift ideas, outings, pink flowers and candy, you name it. And when it comes to food, one common topic of discussion is aphrodisiacs, foods that stimulate sexual desire.
Oysters have long had the reputation of being an aphrodisiac. They say that Casanova, the French adventurer/womanizer, used to eat fifty oysters a day. Perhaps that's what helped him get all the ladies! So does it work? Are oysters really aphrodisiacs? Or is this all a marketing ploy to generate more oyster sales during February?
Until 2005, no research had really been done on the oyster's stimulating properties. It was generally believed to be a placebo effect. So when a team of American and Italian researchers made their findings public, the news made headlines.
According to the researchers, oysters and other bivalves contain rare amino acids (chemical compounds that form proteins)*, which are not commonly found in nature. These two amino acids -- D-aspartic acid (D-Asp) and N-methyl-D-aspartate (NMDA) -- play a role in hormone synthesis. D-aspartic acid has been found to temporarily increase testosterone levels and improve sperm motility. NMDA is an agonist (a substance that initiates a physiological response) that can increase neural excitability. When the scientists injected rats with these amino acids, they found increased testosterone production in males and increased progesterone production in females, hormones that increase libido.**
“Spring, when the molluscs themselves are breeding, is best. There is the highest concentration of these two amino acids then... Oysters have to be eaten raw to be most effective. Cooking them reduces the quantity of D-Asp and NDMA molecules.”
— Dr. George H. Fisher, Barry University
The results of this study sounded very promising, but other scientists are skeptical, pointing out that animal studies may not be relevant to humans, and until a study is done using human subjects, it's hard to conclude that oysters have a direct correlation in increasing libido.
So yes, there is some scientific proof that oysters and bivalves promote sexual desire, but libido aside, there are other reasons why you should be consuming shellfish this Valentine's Day:
Besides the nutritional benefits, shellfish is also a sustainable protein and seafood source. We won't go into all the details because that can be a post all on its own, but know that by choosing shellfish, you're also doing the planet good!
So this Valentine's Day, order a dozen oysters or some steamed mussels. We will thank you, the planet will thank you, and maybe your special someone will thank you too...
*D'Aniello, et al. A specific enzymatic high-performance liquid chromatography method to determine N-methyl-D-aspartic acid in biological tissues. Analytical Biochemistry. 2002 Sep 1; 308 (1): 42-51.
**D'Aniello, et al. Involvement of D-aspartic acid in the synthesis of testosterone in rat testes. Life Sciences. 1996; 59 (2): 97-104.
Topo E, et al. The role and molecular mechanism of D-aspartic acid in the release and synthesis of LH and testosterone in humans and rats. Reproductive Biology Endocrinology. 2009 Oct 27; 7:120.
Dong, F.M. The Nutritional Value of Shellfish. 2009 University of Washington.