Maca root is a Peruvian plant most commonly used to boost libido, support energy and mood, and ease menopause symptoms. It grows at high altitudes in the Andes and has been consumed as food and medicine for centuries. What makes maca unusual among herbal supplements is that its benefits appear to work without directly changing hormone levels, a finding that has intrigued researchers for over two decades.
Sexual Desire and Function
The best-studied benefit of maca is its effect on sexual desire. In a randomized, double-blind trial published in the World Journal of Men’s Health, men who took roughly 5 grams of gelatinized maca daily for 12 weeks showed significant improvements in sexual function scores compared to placebo. At the four-week mark, 70.7% of participants screened positive for symptoms of low testosterone. By the end of the study, that number had dropped. The placebo group, by contrast, showed no sustained improvement after 12 weeks.
Women also appear to benefit. A study of 45 women experiencing sexual dysfunction as a side effect of antidepressants found that 3 grams of maca daily for 12 weeks led to higher rates of symptom remission compared to placebo. This is notable because antidepressant-related sexual side effects are notoriously difficult to treat without switching medications.
How Quickly You Can Expect Results
The timeline depends on the form of maca and what you’re hoping to improve. In one study of athletes, self-reported sexual desire improved after just two weeks of taking maca extract. A separate study using gelatinized maca (a processed, more digestible form) took eight weeks before participants noticed a change. Most clinical trials showing broad benefits in mood, energy, or sexual function run for 12 weeks, so that’s a reasonable timeframe to judge whether maca is working for you.
It Doesn’t Change Your Hormone Levels
One of the most consistent findings across maca research is that it does not alter levels of testosterone, estrogen, or other reproductive hormones in the blood. A study published in the Journal of Endocrinology tracked men taking 1.5 to 3 grams of maca daily for 12 weeks and measured luteinizing hormone, follicle-stimulating hormone, prolactin, testosterone, and estradiol at multiple time points. None of these hormones changed compared to placebo.
This raises an interesting question: if maca doesn’t raise testosterone, how does it improve sexual desire? Researchers believe maca may act directly on target tissues, essentially mimicking some effects of hormones at the cellular level without increasing the hormones circulating in your blood. The plant contains unique compounds called macamides and macaenes that aren’t found in other plants, and these are thought to play a role, though the precise mechanism isn’t fully mapped out.
Mood and Energy
A 2016 study of 175 people found that 3 grams of red or black maca daily for 12 weeks improved both mood and energy scores compared to placebo. The study included people living at low and high altitudes, and the benefits held in both groups. This suggests the effect isn’t tied to altitude adaptation, which had been an earlier theory about why Andean populations prized the root.
Maca has also shown modest benefits for anxiety and depressive symptoms in smaller studies, particularly in postmenopausal women. These effects are generally milder than what you’d expect from pharmaceutical treatment, but for people looking for a nutritional approach to low-grade mood issues, maca is one of the few supplements with any clinical data behind it.
Menopause Symptoms
Several randomized controlled trials have tested maca for hot flashes, night sweats, and other menopause-related complaints. Using standard menopause scoring tools like the Kupperman Menopausal Index and the Greene Climacteric Score, all of the trials showed favorable effects. A systematic review of the evidence confirmed these positive signals but noted that the total number of trials and participants was still too small to draw firm conclusions. In practical terms, maca is promising for menopause symptoms but not yet proven at the level of, say, hormone replacement therapy.
Because maca doesn’t appear to raise estrogen levels in the blood, it may be an option worth discussing with a healthcare provider if you’re in a situation where estrogen-based therapies aren’t appropriate. That said, some studies in women have shown inconsistent results on whether maca modulates certain hormone levels, so this is still an evolving area.
Nutritional Content
Maca is more nutrient-dense than most people realize. By weight, it contains 10 to 16% protein and 8.5% fiber. A 100-gram serving provides about 2,050 milligrams of potassium (roughly half of your daily needs), 150 milligrams of copper, and 8 milligrams of vitamin C. It also supplies iron, though in amounts that vary by variety and growing conditions. Most people take maca as a powder or capsule in doses of 1.5 to 5 grams per day, so you won’t get dramatic nutritional value from supplemental doses alone, but it adds up if you’re blending it into smoothies or oatmeal regularly.
Yellow, Red, and Black Varieties
Maca comes in three color varieties, and they aren’t interchangeable. Yellow maca is the most common, the least expensive, and the mildest in its effects. It’s a reasonable starting point if you’ve never tried maca before. Red maca is rarer and contains higher levels of phytonutrients. It tends to be more stimulating and has been studied specifically for its effects on mood and prostate health. Black maca is the rarest and most expensive variety, with research focusing on its potential benefits for memory, learning, and sperm production.
The 2016 mood and energy study used red and black varieties specifically, so if those benefits are your primary goal, choosing one of those over yellow maca may be worthwhile.
Dosage and What to Look For
Clinical studies have used doses ranging from 1.5 grams to 5 grams per day, with most positive results coming from the 3 to 5 gram range taken consistently for at least 8 to 12 weeks. Gelatinized maca, which has had its starch removed through heating, is easier to digest and was used in several of the major trials. Raw maca powder is also available and tends to be cheaper, but some people find it harder on the stomach.
Maca is generally well-tolerated in studies lasting up to 12 weeks. People with thyroid conditions should be aware that maca contains compounds called glucosinolates, which in large amounts can affect thyroid function. If you have a thyroid condition, it’s worth checking with your provider before adding maca to your routine. The safety data for pregnant or breastfeeding women is limited, so most experts recommend avoiding it during those times.