Psyllium: Debunking the Myths

by Amanda Mills

Let’s face it, there’s A LOT of stigma, hype and superstitions surrounding the ingredient psyllium use in horses. Traditionally, it’s been used for sand clearance in seven-day purges but, do you know why you feed it that way? Do you know about the other benefits that psyllium incorporation offers for your horse’s diet? Does it actually pick up sand? Is there any difference between brands and types? Building on last week’s post discussing the amazing benefits of psyllium, this week we will address some of the common myths associated with psyllium use in horses.

Why is our team at Arenus Animal Health discussing psyllium? There are a few reasons. First and foremost, psyllium is one of the ingredients we use in our Assure products. The Assure line is composed of digestive supplements for horses that can help with issues like colic, loose stool, and other common digestive health issues. We've put years of hard work and research into all of our products at Arenus Animal Health. That means, if we've chosen to include psyllium in one of our digestive supplements for horses, it was very intentional and well researched.

Question: Is it true that horses can build up a resistance to psyllium if used daily?

Answer: No. This is a long-standing myth within the veterinary community that has translated to horse owners and the rest of the equine community. Long ago, a well-known equine internist posed this theory when investigating psyllium use in horses, but it was simply speculation. Because of this, the traditional method of feeding psyllium for one week out of each month was born. There has yet to be a research study confirming or denying the development of psyllium resistance in horses who are supplemented daily. In fact, to date, there are more studies supporting its daily use in horses than discouraging it. And after 10 years of daily use in clinical cases using the Assure products no resistance has been detected.

Question: Does psyllium work by actually “picking up” sand and carrying it out of the digestive tract?

Answer: No. Well that is a conditional no as psyllium can pick up small amounts of sand on it’s “tacky” surface. But to achieve sand removal to any large degree other mechanisms must be in play. Psyllium is a mild laxative that supports motility throughout the digestive tract to some degree. Additionally, and most importantly, psyllium in working through the bacterial microflora increases the levels of butyrate in the hindgut. Psyllium is a valuable and essential energy source for the horse, but also critical in enhancing colonocyte repair and regeneration. This vast improvement in health of the colon leads to improved motility of the GI tract. It works by promoting your horse’s GI tract to work as efficiently as possible so it can expel any excess debris on its own.

Question: Are all equine psyllium supplements created equal?

Answer: No. Think about this in terms of Metamucil; if you’ve ever used this product, you know it comes in a flake form that is dissolved in water. Psyllium, in its most basic form, is a flake, but getting your horse to eat a flake (and eat it in enough quantity to do any good) is next to impossible! It’s a little like trying to feed dry beet pulp or bran flakes.

Thus, most equine psyllium horse supplements are highly processed into pellets to make them more palatable and economical by allowing the inclusion of low-grade psyllium. The problem with this is that, during the processing, the original psyllium flake loses much of its water-binding capacity and, therefore, is unable to function as it normally would once in the digestive tract. Essentially, these products form a “hockey puck” within your horse’s gut!

Sure, they will have some beneficial effects, but you won’t truly appreciate the full benefits of supplementing your horse with psyllium when it is low purity psyllium and highly processed through steam and heat in this form. These products form a “hocky puck” type of “glob” when hydrated in your horse’s colon. Arenus Animal Health uses a proprietary pelleting system that uses high pressure processing of high purity psyllium as found in Metamucil. This means that the flakes are simply pressed together to make the pellets used in Assure Plus and Assure Guard Gold, thereby retaining, it’s original “wispy” form when hydrated and the complete benefits of the original high purity psyllium flake and still placing them in a neat, palatable package!

Question: Isn’t psyllium just for sand removal?

Answer: No. Psyllium could be considered an equine superfood. Historically, because of its laxative effects and the tacky nature, it was used mostly for mechanical sand removal and prescribed for incidences of sand colic or accumulation with variable and at times very disappointing results. However, there have been several advancements in our knowledge and published research demonstrating the many health benefits to horses supplemented with a quality psyllium that is processed in the correct form and fed daily. When processed properly psyllium, along with other key ingredients, can heal the GI tract by encouraging repair and regeneration of colonocytes, while reducing acid and encouraging a healthy microflora. Therefore, psyllium can help pave the way to a reduction in GI disease.

Psyllium has the power to prevent and limit the severity of hindgut ulcers [1] by forming a protective barrier to the mucosa. It’s proven beneficial in repairing the mucosal tissues in horses with a history of colitis [2] along with controlling instances of chronic diarrhea and recurrent colic [3]. It’s even been proven to control blood glucose and insulin levels in horses [4] and can be extremely beneficial to those with metabolic diseases like Equine Metabolic Syndrome, Insulin Resistance and Cushings!

Ready to see the powerful benefits of psyllium for your horse? Shop Assure, Assure Guard, Assure Guard Gold, and Assure Plus today! Only, at Arenus Animal Health.


[1] Sahagun AM, Vaquera J, Garcia JJ, Calle AP, Diez M, Fernandez N, Loro JF, Portilla HO, Sierra M. Study of the protective effect on intestinal mucosa of the hydrosoluble fiber Plantago ovata husk. BMC Complement Altern Med. 2015; 15: 298.

[2] Reuss SM. Updates in the Medical Management of Colic: Moving Beyond Mineral Oil. AAEP Proceedings 2014; 60: 213-218.

[3] Brendemuehl JP, Altman J, Kopp K, Blikslager A. A multi-center clinical trial utilizing a combined probiotic, prebiotic and psyllium product for the management of chronic gastrointestinal disorders (diarrhea and colic) in clinically affected horses. 2010; Novus Nutritional Brands, LLC.

[4] Moreaux S, Nichols J, Bowman J, Hatfield P. Psyllium Lowers Blood Glucose and Insulin Concentrations in Horses. J Eq Vet Sci 2011; 31, 4: 160-165.