Arizona physician Gary Gordon, M.D., former president of the American College for Advancement in Medicine, is also a maca supporter. "We all hear rumors about various products like maca. But using this Peruvian root myself, I personally experienced a significant improvement in erectile tissue response. I call it nature's answer to Viagra.

What I see in maca is a means of normalizing our steroid hormones like testosterone, progesterone and estrogen. Therefore it has the facility to forestall the hormonal changes of aging. It acts on men to restore them to a healthy functional status in which they experience a more active libido."

How Much Maca Should You Take?
Keep in mind that maca is a food, and is not used in tiny quantities. Most supplement companies that are selling maca are putting about 500 milligrams of ground, dried maca in each capsule. Some recommend three capsules daily, some six.

I believe that many people think of herbs like drugs, and assume that small amounts will do some good. In most cases, that's not true. As a rule, consumers take too little of most herbs to derive the benefits those herbs can impart. Rare is the herb that works in small doses. And many herbal product labels offer dosage recommendations based not on efficacy, but on price.

To be consistent with Peruvian use you'd take a minimum of six to ten 500-milligram capsules of powdered maca daily, equal to 3,000 to 5,000 milligrams of maca. You can certainly take more. You can also obtain powdered maca root under some brands. With those products, you can toss a tablespoon full into a blender drink every day and enjoy maca the way the Peruvians do.

MacaPure, which is a standardized, concentrated extract of maca, is a different story. Companies selling MacaPure are recommending one 450-milligram capsule of MacaPure extract twice daily, equal to 900 milligrams of MacaPure extract. I personally think that four to five capsules (between 1,800 and 2,250 milligrams) daily is the right range.

The more maca or maca extract you consume, the more benefit you are likely to get. In toxicity studies conducted in the U.S., maca showed absolutely no toxicity and no adverse pharmacologic effects. In animal studies, the more maca animals consume, the stronger and more sexually active they become. You can be generous with the amounts of maca products you take. With maca, you have a safe, effective, nontoxic way to significantly boost your sexual function, without the hazards of prescription drugs.

[Editor's note: While natural herbs can have many positive effects on your health, including restoring or improving your sex drive, you should discuss the use of specific herbs with your doctor. Most herbs are safe on their own but your doctor can help you know if they can have potential adverse interactions with other medications you may be taking or other health conditions you have.]