From the archives: The 2024 Bluff oyster season is underway – it runs until August – meaning the delicacy is making its way to supermarkets, fishmongers and restaurant tables. But is there any truth to the idea, popular for 100 years, that the molluscs are a natural aphrodisiac? This article, from the Listener’s archives, explores the science behind the belief.
Before there were little blue pills, there were oysters. Men have slurped them down for generations, believing they can enhance libido. Renowned 18th century lover Casanova was so convinced that the molluscs helped when it came to his performance with the ladies that he ate 50 of them for breakfast every day.
Ten years ago a team of American and Italian researchers got very excited – no, not that kind of excited – when their combined study appeared to show just why oysters could in fact be aphrodisiacs.
They analysed bivalve molluscs, which include oysters, and found they were rich in rare amino acids that can lead to increased levels of sex hormones.
When the research was presented at a meeting of the American Chemical Society, it generated more interest than any other discovery in the society’s 126-year history, much to the amazement of the scientists.
Their findings did seem to be groundbreaking. It had always been thought that it was the high zinc content in oysters that made men in particular frisky. Being deficient in zinc can lead to lower levels of testosterone, which in turn results in a low sex drive, so it makes sense that upping your zinc intake should be able to boost your libido by producing more testosterone.
But the Italian/American study came up with another possible reason for the potency of oysters when they isolated two unusual amino acids, known as D-Asp and NMDA.
Injecting these acids in male rats increased the production of testosterone, and the higher the levels of these hormones in the blood, the more sexually active you are likely to be. The scientists stressed that the oysters needed to be eaten raw to be the most effective.
However, before people had the chance to get too worked up about the properties of these amino acids, other researchers pointed out that ingesting a substance did not necessarily have the same effect as injecting it.
Since then, the US Food and Drug Administration (FDA) has come out and said aphrodisiacs are folklore. There have been no conclusive scientific studies that show foods with these so-called abilities can work any better than placebos, it says.
While some small studies have found that foods and products considered to be aphrodisiacs do affect sex hormones, there is no evidence to show that they have enough of an impact to boost sex drive and performance.
Still, if you start eating a healthy diet including foods, like oysters, that provide nutrients the body needs, you may notice improvements not only in general health, but also in specific areas, like sex drive.
If your sex drive is low, it could partly be because your overall health is poor. So, the first step is to overhaul your diet so you’re eating lots of fruit and vegetables, lean protein, whole grains and healthy fats, and cutting out processed junk.
It may also be useful to make sure you’re eating enough foods that encourage good circulation and help to get blood to those all-important parts of the body. Avocados, for example, are a good source of vitamin B6, which promotes better blood flow.
Magnesium helps to keep blood vessels dilated so spinach, broccoli and other green vegetables, along with nuts and seeds, fish and beans, can help to get blood to where it is needed. Magnesium also triggers the production of hormones that modulate sex drive, so it’s important get adequate amounts in your diet.
If you want to increase your zinc levels but can’t stomach oysters, beef and lamb are another source, as are spinach, pumpkin and mushrooms.
Vitamin B12 is another goodie because it helps your body produce red cells and boosts energy. Among other results it can have, it may be able to heighten sex drive and enlarge blood vessels throughout the body, including in the genitals. It also stimulates the secretion of histamine, which is needed for orgasm. Again, those multi-talented oysters are a good source of B12, but you’ll also find it in liver, beef, eggs, salmon and tuna.
Foods you might want to steer clear of because they may lower libido include excessive amounts of soy, and fatty foods that can lead to clogged arteries. Generally, food that’s bad for heart health is also bad for libido.
This story was originally published in the NZ Listener’s May 5, 2015 edition.
