Summary
-
What is maca?
Maca root is sold as a starchy powder or gelatinized powder (which may be more digestible), and as extracts (see "What It Is"). Most clinical studies have used the root powder or gelatinized root powder and may, therefore, be preferable to extracts. -
Health benefits of maca supplements:
Maca is commonly used to increase stamina and sexual function and improve mood, based on traditional use and evidence from preliminary clinical studies, but there are no large, well-controlled, long-term studies to support these uses. Maca does not appear to affect sexual hormones in men or women. (See "What It Does") Although different colors of maca, (i.e. red, black and yellow) are sometimes promoted as having different effects, these claims are based on animal studies, there do not appear to be any studies comparing the effects of different colors of maca in people (see ConsumerTips). -
Maca safety and side effects:
Maca root powder has been consumed for centuries as a food source and is considered fairly safe, but reported side-effects include headache, stomach upset, sleep disruption and increased sweating and it may affect liver function and blood pressure. (See "Concerns and Cautions") -
How much maca should I take?
A typical dosage of maca root powder used in clinical studies is 1,500 to 3,000 mg (less than one teaspoonful), which can be as loose powder mixed with water or into a beverage, or as several capsules. Capsules typically contain about 500 mg of powder. (See "ConsumerTips™") 
What did CL's tests of maca find? Testing by ConsumerLab.com of maca supplements found several to appear to be authentic based on DNA and microscopic testing. However, one product could not be Approved by ConsumerLab.com due to contamination with lead. (See "What CL Found")-
Best value for maca:
Among CL Approved products, the lowest cost per gram (1,000 mg) of powder was 10 cents from a loose maca powder or 12 cents from a loose gelatinized maca root powder. Maca in capsules generally cost a bit more than loose maca powders. (See "Top choices")
