This is maca, a root vegetable from the high altitudes of the Peruvian Andes. It has been cultivated and eaten as a food staple in Peru for well over 2,000 years. Children eat it. Pregnant women eat it. The elderly eat it. It is a dietary crop. It is used at therapeutic doses in supplement form across the world for energy, libido, menopausal symptoms, and fertility support.
It is on a European restriction list of 117 dangerous substances.
**The concern **
Maca belongs to the brassica family the same botanical family as broccoli, kale, cabbage, and Brussels sprouts. It contains glucosinolates sulphur-containing compounds that, in excess and particularly in combination with a low-iodine diet, can interfere with thyroid hormone synthesis, potentially contributing to goitre. This is a real biochemical mechanism, not a manufactured concern.
Additionally, maca has demonstrated hormonal activity in clinical and animal studies — effects on sex hormone levels have been reported, though the clinical evidence is inconsistent and the precise mechanism is not fully characterised. The EU's HoA Working Group noted limited long-term safety data and endocrine-related concerns as the basis for flagging maca.
What the clinical evidence actually shows.
Multiple systematic reviews have assessed the safety profile of maca in human studies. A comprehensive 2024 review in PMC concludes that maca is generally safe, with rare adverse effects, supported by preclinical studies revealing low toxicity and good human tolerance. No serious adverse events have been reported in randomised clinical trials. An 8-week clinical trial published in Frontiers in Nutrition in 2022 found maca supplementation well-tolerated with no reports of major adverse effects.
The most important contextual fact about maca safety is the Peruvian food tradition. Maca is consumed as a staple food in the Andes at levels far exceeding what any supplement delivers. Communities in Junín and Pasco have eaten maca as part of their daily diet for generations without the epidemic of thyroid disorders, hormonal disruption, or reproductive harm that the regulatory concern would imply. That is a multi-century human safety study. It is not randomised. It is not blinded. But it is two thousand years of observational safety data, and it has to count for something.
The glucosinolate issue; who is actually at risk.
The goitrogenic concern from glucosinolates is real, but highly population-specific. It requires both high glucosinolate intake and low iodine status. Populations with adequate iodine intake, which in the UK includes the majority of adults who consume dairy products, seafood, or iodised salt, are not at meaningful risk from maca's glucosinolate content at standard supplement doses. People with pre-existing thyroid conditions or those on iodine-restricted diets should be advised to consult a practitioner before using maca. This is appropriate clinical guidance. It is not a general public health emergency.
The same glucosinolate concern applies to cruciferous vegetables. Eating a large quantity of raw kale is associated with a greater glucosinolate exposure than a standard maca supplement dose. Kale is not on the restriction list.
Long-term safety.
I will acknowledge the genuine limitation: controlled randomised trial data on maca beyond six to twelve weeks in humans is limited. The absence of long-term RCT data does not equal demonstrated harm. Two thousand years of food use is relevant context. But it is an honest evidence gap that a proportionate regulatory response would address through requirement for longer-term safety data — not immediate prohibition.
The proportionality argument.
Maca is a food. It has been eaten safely for millennia. The safety signals that exist are population-specific and dose-dependent. The appropriate regulatory response is: thyroid condition labelling guidance, iodine status advisory for specific populations, and a call for longer-term clinical safety data. Prohibition achieves nothing except removing access to a food-based supplement with genuine evidence of benefit for hormonal health, particularly for menopausal women and for male fertility.
A Peruvian root vegetable. Two thousand years of food tradition. No serious adverse events in clinical trials. And it's on a restriction list because of glucosinolates the same compounds in broccoli.
The UK committed to align food supplement law with EU law under the SPS Agreement — without Parliament voting on it. Published at www.gov.uk/government/news/uk-eu-sps-agreement-legislation-in-scope .
Sign the petition.
Respond to the EU consultation. Write to your MP at writetothem.com. This is about your right to access food — not just supplements.
https://www.change.org/p/demand-uk-regain-control-over-food-supplements-regulation?recruiter=1403120945&recruited_by_id=ca366360-0a66-11f1-a119-071922cd5010&share_id=Qv72WrhZDN #RightToHeal #HerbalAccessNI #SaveOurSupplements