Nutrition is a science which incorporates physiology, biochemistry, organic chemistry and biology. Nutrition is also as much a specialty as Orthopedics, Pharmacology, etc.. Nutrition can be studied at the Masters degree or Ph.D. level.
Veterinarians are not taught much nutrition in school. Neither are M.D.s. Farriers/trimmers, chiropractors, body workers, barn owners, trainers, fellow owners, clerks at the feed store and anyone else you can think of that does not have an advanced animal science or nutrition degree know even less.
Does a horse owner know more than a cat owner? They know more about what is fed to horses but not necessarily why. The why is where the true knowledge of nutrition comes in. What are the calorie, protein, vitamin and mineral requirements? What types of foods and supplements are digestible, bioavailable and well tolerated? What things are toxic and at what level? That’s just the beginning.
Like all science, equine nutrition evolves as we learn more. Some people say changing recommendations means science is basically unreliable and worthless because it can change but that change means it is evolving, refining and improving. It still has a core of basic facts that is the foundation.
Despite the fact that nutrition is a complex science there are myriads of unqualified people doling out nutritional advice, either to sell something or because they want to make a “discovery”. The latest claim I heard is that equine metabolic problems, arthritis and navicular can all be significantly improved by removing sulfates from the diet. This seems to refer to supplements in sulfate form, e.g. copper sulfate. The claim is that sulfate is pro-inflammatory and increases iron absorption. Problem is, that’s not true.
The second problem is the vast majority of the sulfate in the horse’s body comes from water, sulfate in foods and sulfate produced from the sulfur-containing amino acids. Stopping supplements in sulfate form would not have any significant effect – which is a good thing because sulfate is absolutely essential for life and health including production of the most widespread detoxifying, antioxidant and antiinflammatory compound in the horse’s body – glutathione. Bottom line is that the whole thing is ridiculous.
Another one trending at the moment is “whole food” feeds and supplements that claim to provide every nutrient the horse needs, with no supplementation of individual nutrients. I’m surprised the FDA and state Ag departments haven’t caught up with some of these feeds yet. Their own analyses show they are not complete and adequate. The supplements don’t measure up either.
The truth is the more of these unsupplemented “whole foods” you give the horse in place of hay or grass, the more likely you are to have protein and mineral deficiencies. The only thing you can be guaranteed this type of feed gives in adequate amounts is calories.
This list goes on and on. Some of it is just wacky, some actually dangerous especially for special needs situations like metabolic syndrome or myopathies and groups with very high needs for growth, lactation, pregnancy or performance. Remember, nutrition is one of the few major contributors to your horse’s health that is completely within your control. There’s no place for unsubstatiated advice.
Eleanor Kellon, VMD