Omega 3 fatty acids are commonly used in animals and humans as a supplement for various disease conditions. In dogs, they have been shown to be effective for arthritis and skin conditions. The omega 3 fatty acids are commonly fed to horses to help with skin conditions, especially allergies. Fatty acids have been shown to increase the sensitivity of insulin in pigs. Insulin resistance is a major problem in horses because it causes metabolic syndrome, laminitis and founder. Horses that develop equine metabolic syndrome and founder are resistant to the effects of insulin and, if effective, feeding fatty acids would help prevent laminitis in these horses. Veterinarians at Colorado State tested omega 3 fatty acids to see if this supplement would help increase the sensitivity of insulin.

To test this theory, a group of horses were fed both a marine source of omega 3 fatty acids containing fish oil and a plant source of omega 3 fatty acids consisting of flax seeds. Results indicated that insulin-resistant horses had a trend toward increased insulin sensitivity while there was no effect on horses that were not insulin resistant. Overall, there was no consistent effect in feeding fatty acid supplements to increase insulin sensitivity in horses. It is possible the lack of effect in the study could have been related to other factors because horses lost weight during the study, and weight loss also affects insulin sensitivity. The authors indicate that further study of insulin-resistant horses is necessary to determine if larger doses of omega 3 fatty acids may have an effect on increasing insulin sensitivity. However, at this time omega 3 fatty acids should not be considered to make a major difference in insulin sensitivity in horses.