Scientific evidence that supports or counters claims to beneficial effects from nutraceuticals is vital to veterinarians. Documenting that evidence and funding those studies is never simple.
“Controlled efficacy studies are difficult to document,” says Robert J. Van Saun, DVM, MS, Ph.D., a professor in the Department of Veterinary and Biological Sciences at Pennsylvania State University. “The reality is that finding two horses the same age, in the same physical condition, with exactly the same lameness issues creates its own difficulties. Then you give one a supplement and one a placebo. How can you be certain that the results are sound?”
Determining which nutraceuticals benefit the horse’s health and which do not has long been an academic challenge, Van Saun says.
Which Do As Promised?
Products are marketed around specialized ingredients, specific horse activities, forage program and a plethora of other factors and anthropomorphized concepts, Van Saun says. An equine practitioner’s biggest challenge can be clarifying which nutraceuticals do what manufacturers say they will.
“Most of these products have none to limited research validating their effect,” he says. “This is why they are marketed as ‘nutraceutical’ nutritional supplements. The manufacturer wants to sell the product, but not pay for the research required by the Food and Drug Administration to validate any ‘health or medicinal’ effects that are promoted on the label.”
Not many of the supplements available today actually fall into the category of feed additives, which the FDA regulates.
Drug or Supplement?
“Under the current laws and interpretations by the FDA, any substance incorporated into food with the intent to alter animal health, structure or function is considered a drug,” Van Saun says. “It is this claim that brings about the controversy surrounding ‘nutritional supplements’ and ‘nutraceuticals.’”
Under the legal definition of a drug, a substance must undergo extensive evaluation for efficacy and safety, funded by the interested party, before it is permitted for use as a food additive.
Van Saun says marketed feed additives for horses include products like antioxidant mixtures, direct-fed microbials (probiotics and yeast extracts), sea kelp, herbs and botanicals, single-cell protein supplements, various joint supplements (glucosamine, yucca, chondroitin), fatty acid supplements and others.
“For the most part,” he says, “these are not products supplying some essential nutrient, but they are being marketed as products that may facilitate or improve animal performance, health or other facet.”
But most of these products are marketed as nutritional supplements, or nutraceuticals, so are not classified as drugs.
“Beyond safety, a primary concerns in the lack of regulation of nutritional supplements is the tremendous variation in quality control and content of active ingredient,” Van Saun says. He cites studies that have shown many nutritional supplements do not contain as much active ingredient as listed on their labels.
Kathleen Crandell, Ph.D., an equine nutritionist with Kentucky Equine Research Inc. in Versailles, Ky., agrees. KER is a consultant to feed manufacturers formulating top-quality feeds to complement a horse’s typical forage.
“Many nutraceuticals are being used as alternatives for both nutrition and medicine,” Crandell says, adding that some manufacturers make illegal drug claims without proper data to support their safety and efficacy.
“Unfortunately, consumers become the victim because they purchase a product in good faith, not knowing whether the claims have been substantiated,” she adds.
First, Do No Harm
“Above anything else, nutraceuticals should be safe,” Crandell says.
Safety of a nutraceutical product is often easier to establish than efficacy. Studies that test doses of nutraceutical several-fold greater than the recommended dose help to establish toxicity data.
“However, to have any validity, these studies must test animal reaction to the product both short- and long-term,” she says. “By and large, these studies have not been done.”
Do nutraceuticals do what they say they can do?
“Evidence of efficacy is generally provided by studies that document the pharmaceutical, pharmacokinetic and pharmacodynamic characteristics of a compound,” Crandell says.
Published and peer-reviewed studies contribute to nutraceuticals’ scientific integrity for safety and efficacy. Many niche manufacturers conduct their own research, as well as team up with universities and veterinarians.
Gayle W. Trotter, DVM, Dipl. AVCS, was a former joint-health researcher and professor at Colorado State University. While at CSU, Dr. Trotter’s research interests were in equine joint disease.
Referring veterinarians and clients often asked for his opinion on joint-health products, ultimately leading to his developing a joint-health nutraceutical, Myristol, that addresses the soft tissue inflammation that accompanies joint disease. Myristol is now manufactured and sold by MyristolEnterprises of Weatherford, Texas.
Trotter says an independent clinical study documented the efficacy of Myristol in horses that already suffer from joint-related issues, and he says it can also be considered for prophylactic use in equine athletes that may not yet have developed joint disease issues.
Quality Is Good
“Some products rely on anecdoctal evidence, but as a veterinarian, my training encourages me to make the ultimate goal a safe, efficacious, quality supplement,” he says.
Like other supplements on the market, Trotter’s carries the National Animal Supplement Council seal, which means the manufacturer has agreed to implement certain quality standards. The NASC is a non-profit industry group dedicated to protecting and enhancing the health of companion animals and horses throughout the U.S.
Wendy Pearson, Ph.D., has been researching the efficacy of equine nutraceuticals for several years.
She is a research and development consultant for Nutraceutical Alliance Inc., which designs research programs that may help manufacturers achieve regulation for their products. She is also an instructor at the University of Guelph’s Department of Plant Agriculture in Ontario, Canada.
Pearson has presented results from a major four-year research project that studied an anti-inflammatory nutraceutical to the British Equine Veterinarian Association Conference in England and to the American Association of Equine Practitioners in California.
The study was funded by Interpath, a company based in Australia that specializes in research, development and marketing of nutraceutical products for the treatment of inflammatory joint disease.
Pearson’s paper, “Induction of articular inflammation in horses using Intra-articular IL-1, and modulation of response to IL-1 by Sashas EQ, a dietary nutraceutical,” focused on a new equine joint health product. The patented formulation of marine ingredients is coupled with a newly discovered botanical active, Epitalis.
Her second paper on this project’s clinical field study is due to be printed in a special edition of Equine Veterinary Journal, which will publish papers presented at the December 2012 AAEP conference.
Pearson used advanced in-vitro laboratory techniques and in-vivo studies to prove the product’s safety and efficacy. She says her findings demonstrated the product’s anti-inflammatory and chondroprotective properties. Controlled studies have shown significant inhibition of PGE2 and nitric oxide levels, increased viability of chondrocytes, and suppression of the loss of GAGs from cartilage matrix.
Veterinarians who follow nutraceutical development and research are the horse owners’ best ally in choosing the right product to enhance their horse’s health and provide balanced nutrition.
“With so many different choices and marketing propaganda,” Van Saun says, “the horse owner often becomes disillusioned and uncertain about what should be fed. Oftentimes products are fed more in line with the owner’s perception of feeding practices rather than product-based feeding directions. This approach can lead to nutritional problems.”
Plus, Van Saun says, “The efficacy is not always as clear cut as the manufacturers say. As veterinarians, we try to do no harm. So it’s worth having a conversation with the client about different products.”
In evaluating nutritional supplements, he suggests using “the 4 R’s” criteria:
• Response: What effect is expected from this product?
• Research: Is the product backed by nonbiased studies?
• Results: What are the results with your animal?
• Returns: Is it economically beneficial to use this product?
“Ask questions and request information pertaining to the product,” Van Saun says. “Do good comparison shopping with supplements. The reason there are so many supplements available is the fact that money can be made from their sale.”