Iodine is an essential trace mineral in the diets of our horses and ponies and plays many crucial roles. It is vital as a constituent of the thyroid hormones thyroxine (T4) and triiodothyronine (T3). Every cell in the body depends upon thyroid hormones for regulation of their proper function, making them crucial for everything from metabolic rate and body condition, digestive health, fertility, growth and development. Iodine also plays a role in immune function and the integrity of nerve cells and their ability to communicate signals throughout the nervous system of the body.
Many regions in the world have low iodine levels in the soil. Iodine deficient soils are most common in inland regions, mountainous areas, land that frequently floods, and on occasion, some coastal regions. Unless horse diets are adequately supplemented, horses that graze on pastures in these regions and/or consume hay and feed crops grown in these areas, are likely to fall well short of their minimal iodine requirements. Research has also demonstrated reduced uptake of iodine by pastures which have been grown with high levels of nitrogen fertilisers, even in soils with otherwise reasonable iodine levels.
Like many minerals however, too much iodine can be just as problematic as too little iodine. This can easily occur when our horses are given multiple supplements, and/or feeding inappropriate quantities of fortified feeds. An innocent mistake commonly made in relation to iodine supplementation is the use of seaweed supplements. In many cases, this can result in excessive iodine intake.
Many clinical signs and health consequences of iodine excess often mimic those of iodine deficiency. An important reminder that more is not better, and supplementing without taking specific details into account can be detrimental to horse health, fertility, metabolic function, growth and development.
Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.
As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.
