What it is & who it’s for: One of the most commonly fed horse supplement ingredients, MSM is well-known for its antioxidant and other properties which support healthy joints, skin and coat, hooves, the respiratory tract, and other tissues in horses. It provides a highly usable form of sulfur which plays a critical role the formation of proteins such as enzymes, hormones, and immune cells, as well as connective tissue such as bones, tendons, and ligaments.
Source and bioavailability: According to a study by Pratt, MSM has the highest absorption rate (55%) of all the key equine joint ingredients, making it available for use in tissues throughout the horse's body. Although naturally-occurring in foods such as alfalfa and whole grains, the amount of MSM from the horse's diet is unlikely to be a significant contributor compared to supplementing with the pure ingredient.
Serving size: A group of European researchers studied the effects of MSM on biomarkers of oxidative stress in horses following jumping exercise by giving 4,000 Milligrams to an 1100lb horse. While protective benefits were seen from this amount, typical serving sizes range from 5,000-10,000 mg/day, with some equine veterinary dermatologists recommending as much as 10,000-12,000 milligrams twice a day as a loading dose.
Complementary ingredients: A randomized, double-blind, placebo-controlled study showed that the combination of MSM and glucosamine worked better to maintain equine joint health than either ingredient alone.
Toxicity/Side Effects: MSM is one of the least toxic substances in biology, with no known side effects documented in any species to date. It has an excellent track record of safety in the horse.
Not sure which supplement is right for your horse? We have compiled comparison charts so that you can compare active ingredient amounts in the following categories of Joint Supplements and Comfort Supplements.