Yellow maca is the most common variety of maca root, traditionally used as a food and vitality tonic in the Peruvian highlands. It’s primarily valued for supporting libido, mood, muscle health, and fertility. Among the three main maca colors (yellow, red, and black), yellow maca has the broadest traditional use and the most research behind it as a general-purpose supplement.
How Yellow Maca Differs From Red and Black
Maca root comes in several colors, and each has a slightly different phytochemical profile that lends itself to different uses. Black maca is best studied for stamina and adrenal support. Red maca shows the strongest evidence for prostate health and hormone receptor activity. Yellow maca stands out for improvements in musculoskeletal markers, fertility, and mood. A review published in Nutrients confirmed that all three colors show antidepressant effects, but yellow maca has unique research backing its role in muscle health and differentiation.
Because yellow maca accounts for the majority of maca harvested in Peru, it’s also the variety used in most general maca supplements and powders unless a product specifically states otherwise.
Libido and Sexual Function
The most consistent human evidence for maca centers on sexual desire. In a 12-week randomized, placebo-controlled trial of 57 healthy men, those taking 1.5 to 3 grams per day of gelatinized maca root reported improved sexual desire compared to placebo. The effect appeared by eight weeks and did not depend on dose. Notably, the improvement occurred without any measurable change in testosterone or estradiol levels, suggesting maca works through a different pathway than simply raising sex hormones.
A separate pilot study looked at people taking antidepressants (SSRIs), which commonly cause sexual side effects. At the higher dose of 3 grams per day, participants experienced significant improvement in sexual function scores, while those on 1.5 grams per day did not see the same benefit. Libido specifically improved across both dose groups. This is one of the few natural supplements with any controlled data in this population.
Fertility Support
Yellow maca has a long history of use for fertility, and modern research supports that reputation. In a study of nine healthy men taking 1.5 to 3 grams per day of gelatinized maca for four months, researchers observed increased semen volume, total sperm count, motile sperm count, and sperm motility. Animal studies dating back to 1961 first documented maca’s ability to increase fertility in rats, and subsequent research in rodents has consistently shown improvements in sperm production and testicular function.
Importantly, these fertility effects appear to happen independently of hormone levels. Multiple human studies have found no changes in luteinizing hormone, follicle-stimulating hormone, prolactin, or testosterone in men taking maca. The mechanism likely involves the root’s unique bioactive compounds rather than direct hormonal stimulation.
Mood and Antidepressant Effects
All three maca colors have documented antidepressant properties, and yellow maca is no exception. Animal research has linked this effect to reductions in cortisol and the stress hormone ACTH, suggesting maca may help calm an overactive stress response rather than acting as a stimulant. In ovariectomized rats (a model for postmenopausal hormonal changes), maca supplementation produced measurable antidepressant behavior alongside lower stress hormone levels.
For postmenopausal women specifically, doses of 3.5 grams daily for six weeks have been used in clinical settings to address mood-related symptoms.
Muscle Health and Physical Vitality
One area where yellow maca specifically outperforms other varieties is muscle support. When researchers applied yellow maca extracts to skeletal muscle cells, they observed beneficial changes in muscle growth, differentiation, and maturation. The extract activated key signaling pathways involved in building and maintaining muscle tissue, pathways that typically decline with age. This suggests yellow maca may help counteract sarcopenia, the gradual loss of muscle mass that accelerates after middle age.
This research is still in the cell-study phase, not yet confirmed in human trials. But it aligns with maca’s traditional reputation as an endurance and vitality food for people living and working at high altitudes.
Cognitive Function
Maca supplementation improved learning, memory, motor coordination, and endurance in middle-aged mice after five weeks of use. In maze tests, maca-treated mice located hidden platforms faster and showed better memory retention than untreated mice. The cognitive benefits were tied to improved mitochondrial function in the brain’s cortex, essentially helping brain cells produce energy more efficiently. Researchers characterized maca as a functional food with potential for slowing age-related cognitive decline, though human studies on cognition are still limited.
Skin Protection
A smaller but growing body of evidence connects maca to skin health. Maca extracts have been shown to help prevent and improve skin damage caused by UV rays and to promote wound healing at high altitudes by modulating immune function. In laboratory studies, both fermented and non-fermented maca root extracts reduced melanin production in skin cells in a dose-dependent manner, with fermented extracts showing stronger effects. At a 10% concentration, fermented maca extract significantly suppressed the genes responsible for melanin synthesis. These findings point toward potential cosmetic applications for evening skin tone, though this research has not yet moved into large human trials.
Nutritional Profile
Beyond its bioactive compounds, yellow maca is a genuinely nutrient-dense food. Dried maca root contains roughly 10% protein, 59% carbohydrates, 8.5% fiber, and just 2.2% fat. It’s rich in essential amino acids, with particularly high levels of glutamic acid, arginine, leucine, and valine per gram of protein. Over half its fatty acids are unsaturated, with linoleic, palmitic, and oleic acids being the most abundant.
The mineral content is notable: 100 grams of dried maca provides about 2,050 mg of potassium, 150 mg of calcium, 16.6 mg of iron, 5.9 mg of copper, and 3.8 mg of zinc. Fresh maca root is over 80% water, making it a low-calorie food in its whole form. Most supplements use dried or gelatinized powder, which concentrates these nutrients.
Dosage and Safety
Most human studies use between 1.5 and 3.5 grams of maca powder per day, taken for 6 to 16 weeks. Doses up to 3 grams daily appear safe for at least four months based on available clinical data. For sexual function specifically, 3 grams per day has shown stronger results than 1.5 grams in some studies, so the higher end of that range may be worth trying if you’re using it for libido support.
Maca is generally well tolerated. It contains compounds called glucosinolates, which are also found in broccoli and other cruciferous vegetables. These can theoretically affect thyroid function in very high amounts, particularly in people with existing thyroid conditions or iodine deficiency. Gelatinized maca, which has been pre-cooked to remove starch, is often recommended as easier to digest than raw maca powder. If you’re adding maca to smoothies, oatmeal, or beverages, gelatinized powder also mixes more smoothly.