By Dr. Wendy Pearson

Understanding the connection between fats and inflammation

 There are few scientific stories more widely told than that of the friendly fats. In an age besotted with counting calories and cholesterol, how cheerful it is to learn that ‘fat’ need not be four-letter word. In fact, incorporating essential fatty acids into our horses’ diets is one of the simplest ways for us to take control of his overall health.

Fatty acids are a component of cell membranes, and, while some fatty acids are manufactured by the microbial population of the gut, others cannot be manufactured and must thus come from the diet. These fatty acids are termed “essential fatty acids” because they are essential for robust health but must be provided in the diet. One such essential fatty acid is called “alpha linolenic acid” or ALA. ALA is the parent omega-3 fatty acid from which all other long-chain omega-3 fatty acids are derived. Omega 3 fatty acids have attracted a great deal of attention both scientifically and economically, primarily because when they are provided in higher amounts than is typically seen in the equine diet, they displace other types of fatty acids from cell membranes. Why is this important? Well, in situations where the horse is injured or exposed to infectious organisms, his body produces a complex array of molecules which regulate the immune- or inflammatory response. Many of these compounds are produced from the fatty acids which are released from cell membranes. And the types of compounds that are ultimately produced are dependent on the types of fatty acids that are available for release from the cell membranes. For example, when omega 6 fatty acids (such as linoleic acid, or LA) are liberated from cell membranes, they are transformed into inflammatory prostaglandins such as PGE₂.  PGE₂ is very inflammatory and is partly responsible for the pain that a horse feels during injury – in fact, it is the chemical that you are trying to stop from being produced when you give your horse ‘bute’. But if ALA is liberated instead of LA, it forms slightly different prostaglandins, including PGE₁ and PGE₃. These prostaglandins are far less inflammatory than PGE₂ and can prevent inflammatory reactions from being dramatically upregulated.

So how can we increase the percentage of GLA in our horses’ diets? There are a number of vegetable sources of ALA, including flaxseed or flaxseed oil, and hemp or hemp oil. Some horse owners also add fish oils to their horses’ diets, which are rich in omega 3 fatty acids.  Oils that are poor sources of omega 3 fats are corn oils and canola oils. Discuss incorporation of omega-3 fats into your horses’ diets with your veterinarian, and contact your local manufacturer of equine supplements to find out which products may be best for you and your horse.