Be Cautious with Iron

From pregnancy to performance, nothing happens without iron.  Iron is essential for all forms of life; a mineral element that has no substitute and powers key life-sustaining reactions in your horse’s body.  Iron also has an insidious dark side.

The most well know role of iron is in red blood cells, where iron forms the active center of hemoglobin, the pigment which carries oxygen in the red cells. It performs a similar function in the muscle pigment myoglobin, which gives muscle its red color. Iron is needed for thyroid hormone production. Iron containing enzymes are also used inside the cell’s nuclear powerhouses, the mitochondria.

Iron has many functions because chemically it is extremely reactive – almost too reactive. Unfettered iron is like molecules in a nuclear reactor. It can do a tremendous amount of damage to the tissues. In a normal horse, there is virtually no free iron. It is all securely bound to carrier and storage proteins until well controlled and sequestered reactions free it up for use.

Because of the important jobs iron performs, and the fact deficiency is common in humans, iron finds its way into  equine vitamin and mineral supplements and fortified feeds. Iron is a common ingredient in “blood builders” and widely recommended for any horse that is anemic.

However, more is not better for iron and the truth is that equine diets contain more than enough (sometimes much more) iron than the horse needs.  There has never  been a documented case of iron deficiency anemia in an adult horse – ever.  Still, since it’s so important it can’t hurt to supplement anyway, just in case – right? Actually, no.

Because free iron is so dangerous to the body, there is an intricate system to keep it under control. Iron can be absorbed through the gaps between intestinal cells, a process that is increased in the presence of products of fermentation of hay/forage. Otherwise, iron is absorbed into intestinal lining cells in the small intestine. From there, its release into the body is controlled by hormones/regulators that can block movement out of the cell and control the electrical charge of the iron, which in turn determines if it can be picked up by its carrier protein, transferrin.

Once iron is in the body, it is basically there to stay. Unlike other minerals, the body has no avenue  for getting rid of iron other than tiny amounts in sweat. This iron accumulates over time. A high enough dose all at once can kill a horse (foals are especially susceptible) but toxicity is more likely to build up over time.

In 2019, Theelen et al published a paper documenting iron overload and liver damage in horses consuming natural water sources with iron contents of 0.72 to 75.2 ppm at the time of testing. Kellon and Gustafson 2020 described abnormal iron indices in two populations of horses with high insulin levels –  an association that is well established in people, multiple other species of animals and even birds.  Less dire consequences may include anemia, muscle pain, copper and zinc deficiency, poor performance and poor coats from the oxidative stress.

Even unsupplemented diets often contain considerably more iron than the horse needs and levels in the body will rise over time. It makes no sense to add to the burden with the horse’s supplements. Look for the words iron and ferrous in both the analysis and the ingredients list.

Uckele Health & Nutrition, maker of CocoSoya®, offers formulas that contain no iron. 

U Balance Foundation is a broad-based amino acid, vitamin, and mineral pellet that provides generous levels of key nutrients that may be deficient or imbalanced in the horse’s diet.

Equi VM is a vitamin and trace mineral formula concentrated source of vitamins, time-released trace minerals, abundant probiotics, and digestive enzymes for horses of all life stages and activity levels. Does not contain any added Calcium, Phosphorus, or Salt to allow for easy feeding program balancing.

Vitamins and Minerals.  Since no hay or pasture is free of nutrient excesses, deficiencies and imbalances, they are perpetuated and can contribute to many common problems. Uckele’s wide range of minerals and vitamin supplements range from individual nutrients, to targeted ingredient combinations, to a variety of full spectrum products with both vitamins and minerals in formulations to match any need. These include the largest selection of no added iron horse minerals you can find anywhere.

About Dr. Kellon

Dr. Eleanor Kellon, staff veterinary specialist for Uckele Health & Nutrition, is an established authority in the field of equine nutrition for over 30 years, and a founding member and leader of the Equine Cushings and Insulin Resistance (ECIR) group, whose mission is to improve the welfare of horses with metabolic disorders via integration of research and real-life clinical experience.  Prevention of laminitis is the ultimate goal.
Uckele Health & Nutrition, maker of CocoSoya, is an innovation-driven health company committed to making people and their animals healthier.  On the leading edge of nutritional science and technology for over 50 years, Uckele formulates and manufactures a full spectrum of quality nutritional supplements incorporating the latest nutritional advances.