Nutritional supplements do not replace a high-quality diet. | The Horse StaffNutritional supplements dont replace a high-quality diet and appropriate feeding program, yet many owners use multiple products daily. During his presentation at the 2026 EquiSUMMIT Equine Nutrition & Health Conference, hosted by Kemin Industries, Randel Raub, PhD, of Kent Nutrition, raised several important questions for owners to consider when choosing nutritional supplements.Who Regulates Equine Nutritional Supplements?Unlike drugs used to treat or prevent specific health conditions, the industry defines dietary supplements as substances for oral consumption intended for specific benefits other than provision of nutrients beyond normal nutritional needs.Nutraceutical supplements, however, are sold under the premise of being a dietary supplement, but for the expressed intent of preventing or treating disease but that definition now makes them sound like drugs, but unlike drugs these products are not regulated by the FDA, explained Raub.In humans the Dietary Supplement Health and Education Act (DSHEA) regulates manufacturing operations such as quality control and manufacturing standards. The DSHEA does not apply to animal dietary supplements. Instead, the National Animal Supplement Council (NASC), an industry organization, provides some guidelines to animal supplement manufacturers regarding safety and efficacy; however it has no regulatory authority over the manufacturers. Companies that meet NASC standards can use its quality seal on product packaging and advertising.NASC is essentially trying to improve the quality and integrity of nutritional supplements and work with government officials that try to create an environment that is fair, reasonable, responsible, and nationally consistent, Raub said.How Many Supplements Does Your Horse Need?There is no lack of supplements available to consumers, and they are marketed under a lot of different premises and promises, said Raub. Oftentimes owners oversupplement, resulting in the most expensive urine and manure on the planet.In 2008, researchers looked at feeding management practices of top-level eventing horses. They found owners were oversupplementing to the detriment of performance.There is a bell curve ranging from deficient to optimal to toxic, said Raub. Each supplement typically has a laundry list of other ingredients, and when you start stacking supplements you can get a toxic situation.Electrolytes, for example, can be important, especially for horses exercising in hot, humid environments. Some of these products, however, contain excessive added sugars. If the electrolyte supplement you use does not utilize slow-release technology, the horse might respond to a sudden increase in electrolytes by excreting some of them. Repeated electrolyte use over time can exacerbate gastric ulcers, so the form and timing of administration are also important factors to consider, said Raub. Talk to your veterinarian or an equine nutritionist about which electrolyte supplement is appropriate for your horse.Is Your Supplement Cost-Effective?Using biotin as an example, Raub presented three distinct products:Product A, which costs $95.99 for 11 pounds; Product B, costing $64.99 for 9.3 pounds; and Product C costing $140 for 1 pound.Raub recommended considering cost per day per active ingredient when selecting a product. In looking at these options, he found the cost per day per active ingredient was $2.35, $1.09, and $0.75, respectively. So even though the third supplement is expensive for a small amount, it only contains seven ingredients and is only given at small amounts, he said. The initial price doesnt tell you anything.He also warned that some water-based supplements contain mostly water with only small amounts of active ingredients and recommended choosing non-water-based alternatives when possible. Take-Home MessageRegulatory oversight of equine nutritional supplements remains limited. When buying a supplement for your horse, look for a guaranteed analysis, which is different than label claims, said Raub. For example, if it is a biotin supplement, make sure it has biotin on the ingredient list, not just claims or advertising about biotin.Avoid excessive supplementation, which can be detrimental to your horse, Raub said. The better the quality and management of the feeding program, the less reliant owners need to be on supplements.