Is maca bad for you? What the safety evidence shows

For most healthy people, maca is generally well tolerated at the amounts commonly used in supplements. Recent reviews describe it as a plant with rare adverse effects and good human tolerance, and a toxicological review found no serious causes for concern with its food use. That does not mean it is harmless for everyone, at any dose or in any situation.

The short answer: there is no evidence that maca causes serious harm in healthy people at normal doses, but some groups should be cautious and some signs mean you should stop and seek advice. Below we explain what the studies actually measured, what remains unclear, and how to decide with information.

What safety studies show (and what they do not)

One of the most cited human data points comes from a randomised, placebo-controlled 90-day trial in people with metabolic syndrome. In that study, volunteers who took maca together with silymarin (0.8 g silymarin + 0.2 g maca per day) showed no adverse effects; however, in the group that took maca alone (0.6 g per day), a moderate increase in the liver enzyme AST and in diastolic blood pressure was recorded. It is a signal worth attention, especially because it was observed in a specific population (people with metabolic syndrome) and at a relatively high powder dose — it is not an automatic conclusion for someone taking a gummy with 400 mg per serving.

More recent reviews reinforce this reading: maca is considered generally safe, with rare adverse effects, and most preclinical studies show low toxicity. But there is an important limitation: maca's composition varies greatly with ecotype, growing location and post-harvest processing, which makes it difficult to compare studies with each other. A 2024 review of different maca colours highlights precisely that there are still gaps and conflicts in studies on quality, safety and efficacy.

Which side effects have been described?

The effects most often associated with maca are mild and transient. Reviews mainly describe gastrointestinal discomfort, and most people tolerate the product well. In a 90-day trial in people with metabolic syndrome, the group that took maca alone (0.6 g powder per day) showed a moderate increase in AST and diastolic blood pressure.

There are also reports of psychological and mood changes associated with online-sold products containing maca, although those reports come from a context of products for improving sexual function, often with multiple ingredients and no quality control. This does not prove that maca alone causes those effects, but it shows that the market for these products is poorly regulated and that labelling is not always reliable.

Maca and hormones: what is known about the menstrual cycle

Maca contains no hormones. It is a plant in the brassica family, traditionally used in the Andes, and what studies suggest is a possible indirect influence on hormonal processes, not a direct hormonal action.

A systematic review evaluated four randomised clinical trials that tested maca in healthy perimenopausal and postmenopausal women, and all showed favourable effects on menopausal symptom scales. However, the authors themselves classify the evidence as limited, because the number of trials, sample sizes and methodological quality were insufficient. In other words: there is a positive signal, but it is not strong proof.

If you notice menstrual cycle changes that are significant or persistent, the sensible thing is to speak to a healthcare professional before continuing.

Who should be more careful before taking maca

There are situations where caution should override curiosity:

• Pregnancy and breastfeeding: there is not enough data to guarantee safety at these stages. The recommendation is not to take it without guidance from a healthcare professional.
• Children and adolescents: there are no adequate studies in this population and doses should not be given to children.
• Hormone-sensitive conditions (for example, breast, uterine or ovarian cancer, endometriosis, fibroids): because maca may indirectly influence hormonal balance, it should be discussed with your doctor.
• Liver or kidney disease, or medication for those organs: the 90-day trial recorded AST changes in a group that took maca, so monitoring is prudent.
• High blood pressure or antihypertensive medication: the same trial recorded an increase in diastolic blood pressure in the group that took maca alone.
• Anyone taking regular medication: speak to your doctor or pharmacist before starting. You can explore this topic further in the article on maca and medications.

Interactions with medications: what is known and what is missing

Maca's interactions with medications are not well studied. What exists are indirect signals: the increase in diastolic blood pressure observed in a trial in people with metabolic syndrome raises the possibility of caution in those taking antihypertensives, but there are no controlled studies confirming a clinically relevant interaction.

There is also no solid data on anticoagulants, antidepressants or hormonal therapies. The practical rule is simple: if you take regular medication, tell your doctor or pharmacist before starting maca. If you have scheduled surgery, discuss with the medical team whether you should stop the supplement beforehand.

If you have liver or kidney disease, or take medicines that affect those organs, speak to your doctor before starting any supplement, including maca. The same applies if you have diabetes and take insulin or oral antidiabetics: the data on maca's effect on blood sugar levels are insufficient, so monitor your values more often and speak to your doctor. If you have scheduled surgery, it is prudent to stop maca at least two weeks beforehand, since it is not known how it may interact with anaesthesia or other medicines used during the procedure.

Maca in gummies: what changes compared with other forms

There are no studies directly comparing gummies with maca capsules or powder, so it is not possible to claim that one form is superior to another. What is known is that the pharmaceutical form does not change the nature of the plant; it changes the experience of taking it and the excipients involved.

In Hormonal Balance Gummies, each serving of 2 gummies provides 400 mg of maca (black and yellow), among other ingredients. The directions on the label are to chew 2 gummies per day, preferably after a meal, without exceeding the recommended daily dose. The product contains polyols (maltitol), whose excessive consumption may have laxative effects, and it is not recommended for pregnant or breastfeeding women; in case of illness or use of medication, consult a healthcare professional before consumption.

If you are taking maca in gummies, there are a few practical precautions to keep in mind. Gummies contain sugar or sweeteners, which may be relevant if you have diabetes or are trying to control your weight — check the label to know exactly what you are consuming. Chewing is also different from swallowing a capsule: the sugars in gummies stay in contact with your teeth, so if you chew them often, brush your teeth or drink water afterwards. And, as they are attractive to little ones, keep the bottles out of reach of children: a child who eats several gummies may ingest a dose far above the recommended one. If that happens, contact your doctor or pharmacist, or your country's poisons information centre, and seek medical help if symptoms appear.

To compare with what the studies used: the 90-day trial administered 0.6 g of maca powder per day (600 mg), which is higher than the 400 mg per serving in the gummies. This does not mean the gummies are insufficient or that you should take more — study doses are not dosing instructions. It only serves to put the order of magnitude in context.

If you want to understand the differences between formats better, see maca in gummy or tablet form.

Common myths about maca safety

Warning signs: when to stop and seek help

Most effects are mild, but some signs should not be ignored. If you experience difficulty breathing, swelling of the face, lips or throat, or a widespread skin rash, stop taking it and seek immediate medical attention — it could be an allergic reaction.

If you notice intense abdominal pain, persistent vomiting, liver changes detected in blood tests, rises in blood pressure or sudden and unexplained menstrual changes, stop and speak to a healthcare professional. The same applies if common digestive effects do not improve after a few days of reducing the dose or if they worsen.

If a child accidentally ingests several gummies, contact a doctor, pharmacist or poisons information centre immediately. Keep bottles out of reach of younger children.

How to decide with caution

If you are a healthy person, not pregnant or breastfeeding, do not have hormone-sensitive conditions and do not take relevant medication, you can try maca starting with the dose indicated on the label and observing how you feel. If you belong to any of the higher-caution groups, or if you simply have doubts, speak to a doctor or pharmacist first.

It is worth remembering that maca has been studied in few clinical trials, many with small samples and short durations, and that variability between products is great. The absence of evidence of harm is not the same as proof of safety for everyone. To explore what research has already shown about maca's effects, see the article on maca: benefits and what the science says and the maca ingredient page.

Finally, remember that food supplements are not intended to treat, prevent or cure diseases. If you are looking for relief for a specific symptom, the first step should always be a medical consultation.