Ginseng and saffron are sexual performance boosters, according to a new scientific review of natural aphrodisiacs, but while the more obscure Spanish fly and Bufo toad are purported to be sexually enhancing, they produced the opposite result and can even be toxic.  
 
Wine and chocolate are okay, though it's all in your head, say the findings by Massimo Marcone, a professor in Guelph's Department of Food Science, and master's student John Melnyk in Food Research International.

"Aphrodisiacs have been used for thousands of years all around the world, but the science behind the claims has never been well understood or clearly reported," Marcone said.   "Ours is the most thorough scientific review to date. Nothing has been done on this level of detail before now."

Well, a review is not a study so to do a thorough one just means a lot of other people have to do actual studies.  A much harder task.

Currently, conditions such as erectile dysfunction are treated with synthetic drugs, including sildenafil  and tadalafil but natural products that enhance sex without negative side effects would be welcome for many.

"But these drugs can produce headache, muscle pain and blurred vision, and can have dangerous interactions with other medications. They also do not increase libido, so it doesn't help people experiencing low sex drive," said Marcone.

The researchers examined hundreds of studies on commonly used consumable aphrodisiacs to investigate claims of sexual enhancement — psychological and physiological - and say they  included only studies meeting the most stringent controls.    The results said panax ginseng, saffron and yohimbine, a natural chemical from yohimbe trees in West Africa, improved human sexual function.

People in studies reported increased sexual desire after eating muira puama, a flowering plant found in Brazil; maca root, a mustard plant in the Andes; and chocolate. Despite its purported aphrodisiac effect, chocolate was not linked to sexual arousal or satisfaction, the study said.

"It may be that some people feel an effect from certain ingredients in chocolate, mainly phenylethylamine, which can affect serotonin and endorphin levels in the brain," Marcone said.

Alcohol was found to increase sexual arousal but to impede sexual performance.

Nutmeg, cloves, garlic, ginger, and ambergris, formed in the intestinal tract of the sperm whale, are among substances linked to increased sexual behavior in animals.

While their findings support the use of foods and plants for sexual enhancement, the authors urge caution. "Currently, there is not enough evidence to support the widespread use of these substances as effective aphrodisiacs," Marcone said. "More clinical studies are needed to better understand the effects on humans."