Supplements and hormones
Maca Root What the Evidence Shows
Reviewed by a qualified clinician · analysed at UKAS-accredited UK labs (ISO 15189)
Last reviewed September 20265 min read
Every Helvy guide is written by our health editors, then checked by a qualified clinician before it goes live and re-checked as the science moves. We name clinical roles, not individuals, until each reviewer has agreed to be credited publicly. This is wellness guidance to help you understand your own data, not a diagnosis.
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Maca is a root vegetable from the Peruvian Andes, sold as a powder or a capsule. A systematic review of four randomised trials found only limited evidence on sexual function, and said the trials were too small to draw firm conclusions. In one of them, testosterone did not change.
Not sure which markers you need? Build your test →Maca gets talked about like a hormone in a jar. Flat drive, flat energy, and a root from Peru is the answer.
The research is more modest than the marketing. Here is what has actually been tested, and what it does not tell you.
1. What is maca?
A root vegetable. It grows high in the Peruvian Andes and it is a relative of radish and broccoli, which is why the raw powder tastes faintly of cabbage.
You will see it sold in three ways. Raw powder, gelatinised powder, which has been heat-treated to make it easier on the stomach, and capsules of dried extract. Labels often quote a big number such as 5000 mg, which is the raw-root equivalent rather than the weight in the capsule.
It is a food, not a medicine. That matters for what anyone selling it is allowed to tell you.
2. What do the trials actually show?
Not much, and the reviewers said so themselves. A team searched 17 databases and found four randomised placebo-controlled trials of maca and sexual function. Two suggested an effect, one found none in healthy cyclists, and one looked at erectile dysfunction.
“The total number of trials, the total sample size, and the average methodological quality of the primary studies were too limited to draw firm conclusions.”
The same review added that current knowledge of the risks of taking maca is insufficient. So the honest summary is thin evidence either way, not proof that it works and not proof that it does nothing.
3. Does maca raise testosterone?
Not in the trial built to ask that question.
A 12-week randomised trial gave healthy men aged 21 to 56 either 1,500 mg of maca, 3,000 mg, or placebo. The researchers reported that serum testosterone and oestradiol levels were no different between the maca and placebo groups. Any change in how the men rated their sexual desire was independent of those hormones.
The title of that paper says it out loud: sexual desire and its absent relationship with serum testosterone levels. Whatever maca is doing, moving your testosterone is not the reported mechanism.
4. So what should you do with that?
Work out what you are actually trying to fix, and in what order.
Most people reach for maca because drive or energy has dropped. That is a symptom with a long list behind it. Low testosterone is on the list. So are thyroid problems, low iron, poor sleep, low mood and alcohol.
A powder cannot tell you which one you have. A blood test can at least narrow it. Our guide to low libido blood tests sets out the markers behind that symptom, and testosterone booster supplements reviews what else in this category has been tested.
If you do try maca, give it a fixed run and a number to judge it by. Measure before, keep everything else steady, measure again after three months.
5. What dose was used, and who should be careful?
The trials above used 1,500 mg to 3,000 mg of maca a day, taken for 8 to 12 weeks. Shop labels vary wildly, so read the small print rather than the front of the tub.
- Pregnancy and breastfeeding. Not studied properly. Leave it.
- Thyroid medicine. Maca is a brassica, the same family as cabbage and broccoli. Ask your GP or pharmacist before adding a daily dose.
- Hormone-sensitive conditions. The safety data is thin, as the review said. That is a conversation with a qualified clinician, not a comment thread.
Food supplements are not a substitute for a varied diet or for medical advice.
6. Which blood test gives you the before and after?
Helvy’s Complete Male Hormones panel (£119) reports total testosterone with free testosterone, SHBG, LH, FSH, prolactin, DHEA-S and albumin. That is the set a clinician reads together rather than one figure on its own.
Two honest limits. Testosterone peaks early in the morning, so sample then or the number reads low for reasons that have nothing to do with any supplement. And one reading settles nothing by itself, which is why our testosterone blood test guide explains when a repeat is worth doing.
Not sure which panel fits? The build-my-test tool walks you through it, and the men’s hormones hub collects the rest.
READY TO TEST?
Measure first, then decide
Helvy’s home blood tests report your hormones as a set, so you can tell whether a supplement changed anything or whether the problem was somewhere else. Samples are processed by UKAS-accredited UK labs.
Frequently asked questions
Does maca raise testosterone?
In a 12-week randomised trial of healthy men, serum testosterone and oestradiol were no different between the maca and placebo groups. That trial reported no hormonal change.
How strong is the evidence for maca?
Weak. A 2010 systematic review found four randomised trials and concluded the number of trials, the sample sizes and the methodological quality were too limited to draw firm conclusions.
What dose did the trials use?
Between 1,500 mg and 3,000 mg a day, taken for 8 to 12 weeks. Shop labels often quote a raw-root equivalent instead, so the figure on the front is not always the dose inside.
What is the difference between raw and gelatinised maca?
Gelatinised maca has been heat-treated to remove starch, which many people find easier to digest. It is a processing difference, not a different plant.
Is maca safe?
It is eaten as a food in Peru, but the 2010 review said current knowledge of the risks of taking it is insufficient. Avoid it in pregnancy, and ask a clinician first if you take thyroid medicine.
How would I know if it was working?
Pick a marker and a timeframe before you start. Measure your hormones, keep sleep and training steady, then measure again after about three months and compare.
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