Maca root

What is maca?

Maca (Lepidium meyenii) is a root vegetable in the cabbage family that grows at very high altitudes in the Peruvian Andes. It has been eaten as a nutrient-dense food for centuries and has a traditional reputation for boosting energy and fertility. Maca root is sold as a powder, in capsules and in extracts, and it comes in several colors (yellow, red, black and others). A 2024 review in Nutrients points out that color, growing location and processing can change maca’s nutrient and phytochemical profile, and that most studies do not specify which type was used. The authors of that review disclose a commercial interest in a maca supplement company, which is worth keeping in mind.

What the research says

Maca’s best human evidence concerns sexual desire and related outcomes. In a 12-week randomized, double-blind, placebo-controlled trial in men aged 21 to 56, 1,500 mg or 3,000 mg of gelatinized maca per day improved self-reported sexual desire from week eight onward, without changing testosterone or estradiol levels. Other small trials have looked at mood, menopausal symptoms and semen quality, with mixed and generally low-quality evidence.

For blood sugar, the evidence is essentially absent. We did not find human trials showing that maca improves fasting glucose, A1C or insulin sensitivity. In blood sugar formulas it is generally marketed for energy, which is a subjective outcome that has not been tested in the context of glucose control.

How it’s used in supplements

Clinical studies have generally used 1.5 to 3 grams of maca root powder per day. Many multi-ingredient products contain only a small fraction of that, especially when maca is one of many ingredients in a proprietary blend measured in milligrams. At those amounts, effects similar to the trials are unlikely.

Maca is widely eaten as a food in Peru and appears to be well tolerated in short-term studies. Because it is sometimes promoted for hormonal effects, people with hormone-sensitive conditions, and those who are pregnant or breastfeeding, should ask a doctor before using concentrated maca supplements. Raw maca may cause digestive discomfort for some people, which is one reason gelatinized (pre-cooked) maca is common in supplements.

If your goal is steadier blood sugar, maca is not the ingredient to focus on. Its presence in a glucose formula is best seen as an energy-themed extra. People who want to try maca for its traditional uses can buy it as a food powder and use amounts similar to those in trials, which is easier to judge than a few milligrams hidden inside a blend. As with any supplement, tell your doctor what you take, especially if you are managing a chronic condition or take prescription medicines.