So much for those carnivore’s favorites. Yet vegetarians and vegans need to watch their choices as well. When it comes to plant-based protein sources, some doctors and nutritionists believe that soy products may decrease men’s libido. In 2011, the journal Nutrition published a case study of a 19-year-old vegan man who reported sudden-onset libido loss and erectile dysfunction after consuming a diet rich in soy products for several months. Researchers monitored him and found that “full sexual function was regained one year after cessation of the vegan diet” and that at this point, his blood levels of “total and free testosterone,” which had decreased while he was on the diet, had also returned to normal levels. They therefore concluded that the estrogenic properties (that is, those that emulate the female sex hormone estrogen) of soy’s isoflavones caused his testosterone levels—along with his sexual desire—to drop. Of course, eating an occasional tofu stir-fry isn’t going to cause guys to suddenly lose interest in sex. “But if you are vegan or vegetarian, it’s probably best not to lean on soy products for your nutritional needs, and instead drink almond milk rather than soy milk and mix in lots of vegetables, whole grains, legumes, and fruits,” says Berman.
Like soy, certain herbs are also thought to have estrogenic properties; ironically, some guys even take these herbs as natural alternatives to Viagra to prolong the length of intercourse. Marjoram, for example, has been used for centuries as a sleep aid, headache cure, and general relaxant, and though it has been used to treat painful menstruation in women, it is also thought to have anaphrodisiac properties for both men and women, says Reiley. And a 1999 study at the University of Padua (reported in the New England Journal of Medicine) looked at licorice root, which is found not only in candy but also breath fresheners and flavoring agents, and its affect on male libido. The authors determined that eating even just a quarter-ounce of licorice root daily (according to the study, this amount is “eaten by many people”) could reduce testosterone levels. (Simply put, glycyrrhizic acid, which is the active ingredient in licorice, blocks the enzyme that is responsible for making testosterone.)
Although diet is certainly a factor in stimulating or suppressing sex drive, it’s widely accepted that one of the strongest anaphrodisiacs isn’t edible but potable: alcohol. Reiley likes to quote Shakespeare, who wrote in Macbeth that drinking “provokes the desire, but it takes away the performance.” One or two glasses of wine can encourage relaxation, but overindulging can dull your senses and suppress libido. “It’s true that alcohol lowers inhibitions, but it also acts as a depressant, so it can lower erectile function and the ability to reach orgasm,” explains Berman. In Reiley’s view, beer—even when consumed in moderation—behaves as an anaphrodisiac, for two reasons: It contains hops (another herb with estrogenic properties), and its effervescence tends to cause bloating. “I know that many beer lovers will disagree with me, but the theory about hops began when it was discovered that many hops pickers became infertile in the early days of the Western beer industry, and it’s still considered an anaphrodisiac today,” she says.
Drinking in moderation, eating a varied diet in sensible portions, and steering clear of heavy, greasy foods: This prescription for sexual success isn’t too different from what nutritionists and doctors have been advising patients to do to improve their overall health for years. “There’s an argument in favor of eating well to feel sexy,” Reiley agrees, “because if you’re eating meals that have fewer calories and saturated fats, you’ll have more energy, better skin, and less bloating, all of which prime you to want to engage in a sexual situation.”
Brooklyn-based Lexi Dwyer is a former editor at Epicurious and Brides magazine. Her writing has appeared on BonAppetit.com, iVillage, and NYMag.com. Her previous contribution to Gourmet Live chronicled the history of the California roll.