ADVISORY: Maca Root and Root Extract Bulletin: undeclared addition of flour from corn, wheat, or yam to maca root products

Node Smith, ND

ABC-AHP-NCNPR Botanical Adulterants Prevention Program

AUSTIN, Texas (September 17, 2018) — The ABC-AHP-NCNPR Botanical Adulterants Prevention Program (BAPP) has released a Botanical Adulterants Prevention Bulletin on maca (Lepidium meyenii, syn. L. peruvianum, Brassicaceae) root* and root extract. Maca roots have been cultivated in the Peruvian Andes for thousands of years as a nutritious food, and have a history of use as medicine to enhance fertility, to provide energy, and for their effects on mood and well-being.

Use of maca as a dietary supplement is relatively recent

The use of maca as a dietary supplement is relatively recent; it was a little-known ingredient in the United States market prior to 2000. Maca retail sales have started to increase over the last decade, holding steady in the US since 2015. US retail sales exceeded $15 million in the natural and mainstream channels combined in 2017, according to the American Botanical Council’s annual “Herb Market Report” that was recently published in HerbalGram issue 119. Maca ranked 8th in the natural channel and 36th in the mainstream channel.

Reports have been published indicating the undeclared dilution of maca root powders with flour from corn, wheat, or yam

While maca is originally an Andean crop, its popularity in the past few years, especially in Asian countries as a means to enhance sexual stamina, has led to large amounts being grown in China from roots smuggled out of Peru, leading to much uncertainty about supply volume and pricing. At the same time, reports have been published indicating the undeclared dilution of maca root powders with flour from corn, wheat, or yam. As with other herbal ingredients marketed to boost sexual stamina, there is also evidence of the illegal sale of conventional sexual enhancement drugs (e.g., sildenafil) masquerading as maca dietary supplements.

The maca bulletin was authored by Jeremy Stewart, PhD, vice-president of scientific affairs at herbal products manufacturer Gaia Herbs (Brevard, NC), and Bill Chioffi, former vice-president of global sourcing and sustainability at Gaia. It summarizes the published data on maca adulteration, details supply chain issues and their consequences for the maca market, and discusses maca’s market importance. It also includes a short section on analytical methods to detect adulteration. Fifteen experts in quality control of medicinal plants from academia and the herb industry in the U.S. and Europe have provided input on the bulletin during the peer-review process.

“Maca is an example of a formerly obscure herb that has enjoyed recent popularity, and with this increased demand, unscrupulous suppliers have tried to take advantage of consumers by offering maca material adulterated with undisclosed lower-cost ingredients,” said Mark Blumenthal, founder and executive director of ABC and the director of BAPP. “We are deeply grateful to our friends at Gaia Herbs for their compilation of published data and technical information for the maca bulletin.”

Stefan Gafner, PhD, chief science officer of ABC and technical director of BAPP, commented: “The adulteration of maca root ingredients, or any botanical ingredient adulteration, with undisclosed lower-cost material, is unacceptable. It is our hope that these issues will altogether disappear once the supply chain has stabilized. Nevertheless, maca dietary supplement manufacturers should be aware of the potential authenticity issues that can occur.”

The maca bulletin

The maca bulletin is the 16th publication in the series of Botanical Adulterants Prevention Bulletins and the 44th peer-reviewed publication published by BAPP. As with all publications of the program, the bulletins are freely accessible to all ABC members, registered users of the ABC website, and all members of the public on the Program’s website (registration required).

The goal of the Botanical Adulterant Prevention Bulletins is to provide accounts of ongoing issues related to botanical identity and adulteration, thus allowing quality control personnel and lab technicians in the herbal medicine, botanical ingredient, dietary supplement, cosmetic, herbal tea, conventional food, and other industries where botanical ingredients are used to be informed on adulteration problems that are apparently widespread and/or imply safety concerns.

About the ABC-AHP-NCNPR Botanical Adulterants Prevention Program

The ABC-American Herbal Pharmacopoeia (AHP)-National Center for Natural Products Research (NCNPR) Botanical Adulterants Prevention Program is an international consortium of nonprofit professional organizations, analytical laboratories, research centers, industry trade associations, industry members, and other parties with interest in herbs and medicinal plants. The program advises industry members, researchers, health professionals, government agencies, the media, and the public about the various challenges related to adulterated botanical ingredients sold in commerce. To date, more than 200 US and international parties have financially supported or otherwise endorsed the program.

Program has published 44 peer-reviewed articles

The program has published 44 peer-reviewed articles, including Botanical Adulterants Prevention Bulletins, Laboratory Guidance Documents, and Botanical Adulterants Monitor e-newsletters. All of the program’s publications are freely available on the program’s website.

* Technically, in the case of maca, the plant part used is a tuber consisting of the root and the hypocotyl, the stem of a germinating seed just above the root.


Node Smith, ND, is a naturopathic physician in Portland, OR and associate editor for NDNR. He has been instrumental in maintaining a firm connection to the philosophy and heritage of naturopathic medicine among the next generation of docs. He helped found the first multi-generational experiential retreat, which brings elders, alumni, and students together for a weekend camp-out where naturopathic medicine and medical philosophy are experienced in nature. Four years ago he helped found the non-profit, Association for Naturopathic ReVitalization (ANR), for which he serves as the board chairman. ANR has a mission to inspire health practitioners to embody the naturopathic principles through experiential education. Node also has a firm belief that the next era of naturopathic medicine will see a resurgence of in-patient facilities which use fasting, earthing, hydrotherapy and homeopathy to bring people back from chronic diseases of modern living; he is involved in numerous conversations and projects to bring about this vision.

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