Regulation of Equine Supplements

The following is an in-depth explanation of the supplement regulation issue. For a condensed version, visit

For nearly six years, the Food and Drug Administration (FDA) has looked at many animal nutritional supplements as illegal. In April 1996, the Center for Veterinary Medicine (CVM) published a notice in the Federal Register outlining the reasons why the FDA believes Congress did not intend for a law that allows human supplements to be manufactured and marketed legally to do the same for supplemental products used for animals. There now is a groundswell of state regulators who want to crack down on illegal ingredients in animal products, and equine products will not be immune.

The Federal Food, Drug, and Cosmetic Act (hereafter called the Act) defines a drug as an article intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease or an article intended to affect the structure or function of the body other than food. The Act defines a food as something that provides nutrition, taste, or aroma. But, if a product affects the structure or function of the body apart from its nutritive value, such as improvement in joint function, it can be considered a drug.

According to Sharon Benz, PhD, PAS, a member of the United States Department of Agriculture’s (USDA) Nutrition and Labeling Team in the Division of Animal Feeds, Center for Veterinary Medicine (CVM), “Structure/function effects extending beyond the ‘food’ umbrella also include claims for improved or increased production and performance, or alteration or improvement in function.”

The CVM has primary responsibility for enforcing the Act to ensure that animal foods, including pet and horse foods, are safe and labeled appropriately and animal drugs are safe and effective. Ingredients which have not been approved for use in these specific animals are not allowed to be sold and can be pulled from the shelves by state regulators.

When substances (including those considered food) are intended to be used for the “treatment or prevention of disease or ‘non-food’ structure/function effects, they ‘become’ drugs, according to Benz. Under the law, a new animal drug must be shown to be safe and effective for its intended use by adequate data from controlled scientific studies as part of a New Animal Drug Application.

“If a product on the market is not approved, it may be deemed an adulterated drug and subject to regulatory action.”

Some substances are considered “generally recognized as safe” (GRAS) under the conditions of their intended use and are not “food additives.” As such, they are exempt from having to be approved by FDA, said Benz. The CVM can use regulatory discretion and not require specialized paperwork called a Food Additive Petition for substances that do not raise any safety concerns. In those cases, the CVM asks the company to submit the information needed to list the ingredient in the official publication of the Association of American Feed Control Officials (AAFCO).

The FDA cooperates with AAFCO for the implementation of uniform policies for regulating the use of animal feed products. AAFCO is a non-profit organization made up of state animal feed regulators and federal representatives. The group has no regulatory authority, but because its members are state and federal regulators, most of its recommendations are adopted verbatim by states.

According to the association’s web site, “A basic goal of AAFCO is to provide a mechanism for developing and implementing uniform and equitable laws, regulations, standards, and enforcement policies for regulating the manufacture, distribution, and sale of animal feeds; resulting in safe, effective, and useful feeds.”
Sharon Senesac, assistant-secretary/treasurer of the AAFCO, said regulators are targeting ingredients, not an industry. She noted that each state has laws governing animal feed, including those for horses, pets, and livestock. Supplements are covered by laws requiring products be approved before they can be sold. States have regulatory authority, she explained, but the CVM/FDA could supercede that authority. AAFCO also publishes a uniform label suggestion.

Senesac said the goal of AAFCO is to develop model regulations that ensure a level playing field for all products based on their ingredients, and to ensure that products contain legal ingredients that are manufactured and labeled properly.

State regulators have the right, under their state laws, to inspect manufacturing plants, run analyses on products and feeds, and regulate all of those products within their jurisdiction. They also help educate companies on how to get ingredients through the “ingredient definition” process that allows them to be legally sold.

One state regulator said that there has been a marked increase over the last 15 years in the number of companies selling supplements, and that more “fringe” companies might be producing unsafe products. While efficacy (does it work) is important, safety is the paramount concern. And that means safety not only for the animal, but for humans and the environment.

To address the current situation, FDA and AAFCO are working to establish procedures to evaluate the use of “novel” ingredients in animal foods, said Benz. In 1999, AAFCO created the Novel ingredient Task Force to develop a regulatory scheme for these ingredients.

“Botanicals and herbs are part of a group of substances recognized by AAFCO as ‘novel ingredients’,” said Benz. The Novel Ingredient Task Force recommended a standing committee be formed to specifically address botanical and herbal ingredients.

The Botanical and Herbs Committee met for the first time at the AAFCO’s meeting in January 2000 and again in July of that year. It surveyed the animal feed industry to determine which ingredients were on the market or used by animal health care professionals. The survey showed that there were about 180 botanical species being marketed or used by animal health care professionals in the United States. The Botanical and Herbs Committee has since disbanded from lack of industry (manufacturer) interest and cooperation, according to one AAFCO member.

Cause for Concern?

“California investigators in 1998 found that nearly one-third of 260 imported Asian herbal remedies were either spiked with drugs not listed on the label or contained potentially hazardous levels of lead, arsenic, or mercury,” noted Benz. “The potential for diversion of such hazardous products or their by-products for use in food-producing animals is a matter of serious safety concern.

“Use of herbal products in lieu of veterinary care is also a concern,” she continued. “For example, in one country, comfrey is purported as a drench for swine to treat ‘fevers.’ It also is recommended as a treatment for dogs after hip dysplasia surgery. Some other oral uses of comfrey in dogs include treating rickets, arthritis, and rheumatism. For livestock, it is recommended as a treatment for ulcers, arthritis, and rheumatism. In the U.S., comfrey has been marketed in horse products as an anti-inflammatory and to promote wound healing. No published studies could be found to support these medicinal claims.

“Moreover, there are several dangers associated with the use of comfrey. Comfrey contains at least eight pyrrolizidine alkaloids (PA). PAs are hepatoxins and can cause irreversible liver damage. Since the alkaloid effects are cumulative, it may be difficult to associate the damage to the liver with alkaloids in comfrey. Sometimes toxicity signs will not be present until an animal is stressed by something that requires greater liver function (e.g., lactation). Also, the leaves and roots of comfrey have been shown to be carcinogenic (cancer causing).”

How to Get Legal

There are several ways to have an ingredient approved, according to Benz. A Food Additive Petition contains a description of the chemical identity, manufacturing process and controls, analytical methods, utility data, human food safety data, target animal safety data, product labeling, and in some cases an environmental assessment. The CVM reviews the data to ensure the ingredient has utility and can be manufactured consistently to meet product specifications.

Regulatory discretion offers the manufacturer the opportunity to present its case to the FDA, and not have officials approve an ingredient’s use, but agree not to regulate it.

“Although ingredients used under ‘regulatory discretion’ are still unapproved food additives, we agree we will not take regulatory action as long as the labeling is consistent with the accepted intended use, the labeling or advertising does not make drug claims, and new data are not received that raise questions concerning safety or suitability,” said Benz.

She noted that a GRAS substance “is GRAS only for an intended purpose. For example, sodium aluminosilicate is GRAS as an anti-caking agent. It has been purported to bind mycotoxins and prevent absorption from the intestinal tract, but would not be GRAS for this use. (This brings up the question of whether mycotoxin binders being used in horse feeds during the mare reproductive loss syndrome last year are, in fact, legal. More on that in an upcoming article.)

“A food substance also cannot be GRAS for the prevention, treatment, or mitigation of a disease, noted Benz. So, chondroitin sulfates cannot be GRAS to prevent or treat arthritis. For this use, it would be a drug.”
However, states can allow, under their laws, the sale of that ingredient under the proper labeling.

Benz pointed out that general recognition of safety of a substance for an intended use can only be based on the views of experts qualified by scientific training and experience to evaluate the safety of the substance. As interpreted by the FDA and the courts, she said there are two requirements that must be satisfied before a substance can be GRAS; general recognition and safety.

“1. For general recognition, there must be an expert consensus that the substance is safe for use as a component of food, and;

“2. This expert consensus of safety must be based on either (a) generally available data and information to show common use of the substance in animal feed prior to 1958, or (b) scientific procedures, which require the same quantity and quality of scientific data for FDA approval of the substance as a food additive. In addition, this information must be published in the scientific literature.

“Both of these requirements must be met for a substance to be considered as GRAS.”

Dietary Supplement Act

In 1994, the Dietary Supplement Health Education Act (DSHEA) amended the Act to define a dietary supplement as a product intended to supplement the diet and that contains at least one or more of the following--a vitamin; a mineral; an herb or other botanical; an amino acid; a dietary substance for use to supplement the diet by increasing intake; or a concentrate, metabolite, constituent, extract, or combination of any of the previously mentioned ingredients. Benz said the main effect of DSHEA was to remove certain dietary ingredients from regulation as food additives, which requires pre-market approval.

“Thus, products marketed as dietary supplements for humans still fall under the pre-DSHEA regulatory scheme when marketed for animals; that is, they are considered food, food additives, new animal drugs, or GRAS depending on the intended use,” explained Benz. “For most of these types of products on the market, they would be considered unapproved and unsafe food additives or new animal drugs based on current intended use.”
Benz added that, “With regard to claims, we emphasize that an animal food label must not state and/or imply that the introduction of the product in the animal’s body results in a physiological or therapeutic effect. Under the Act, claims in or on animal feed products that establish the intended use to cure, treat, prevent, or mitigate disease identify the intent to offer the product as a ‘drug.’

“In addition, claims that establish the intended use or affect the structure/function of the body in a manner other than food (nutrition, aroma, or taste), identify the intent to offer the product as a ‘drug.’ However, statements associating the nutrients in the product with their ‘known’ functions may be acceptable provided they are truthful and not otherwise misleading.

“On a case-by-case basis, CVM has allowed references to ‘nutritional support’ for specific organs or body functions. For example, we would not object to a claim that an animal food product contains vitamin E for prevention of fat oxidation in the feed or serves as an antioxidant in the body.”

Circulating e-mails from concerned horse owners and veterinarians encourage horse owners to contact the FDA and oppose the crackdown on animal nutritional supplements. However, Benz says that the FDA’s role is clear—it is charged with enforcement of laws, not creation or interpretation of laws. If horse/pet owners want the same exemptions as humans got with DSHEA, then they need to write their Congressmen to have a law or amendment passed telling the FDA to leave nutritional supplements alone. For a listing of congressional contact information see

Following is a list from Dr. Benz of unapproved herbs currently marketed for use in animals. The herbal plant common name is followed by its scientific name in parenthesis. “It is noted that most of these plants are also known by other common and scientific names.”

Herb Claims
Arnica (Arnica spp.) Anti-inflammatory and stimulant
Boneset (Eupatorium perfoliatum) Vasodilator and antispasmodic
Burdock (Arctium spp.) Digestive aid; improve liver and kidney function
Clivers (Galium aparine) Diuretic; treatment of urinary problems
Comfrey (Symphytum officinale) Anti-inflammatory; promote wound healing
Devil’s Claw (Harpagophytum procumbens) Anti-inflammatory; alternative to Bute
Echinacea (Echinacea angustifolia) Improve function of the immune system
Ginseng (Panax ginseng) Enhance immune system; promote lung function
Horsetail (Equisetum arvense) Promote healing of connective tissue; acts as a diuretic
Ignatia amara Sedative
Nettles (Urtica dioica) Diuretic; treat anemia
Uva-Ursi (Arctostaphylos uva-ursi) Diuretic; urinary antiseptic
Valerian (Valeriana officinalis) Sedative
White willow bark (genus Salix) Arthritis; anti-inflammatory
Yucca (Yucca schidigera) Arthritis


About the Author

Kimberly S. Brown

Kimberly S. Brown was the Publisher/Editor of The Horse: Your Guide To Equine Health Care from June 2008 to March 2010, and she served in various positions at Blood-Horse Publications since 1980.

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