Q.I’m looking at supplements designed to support gastric health for my horse that’s recovering from equine gastric ulcer syndrome (EGUS). Several products say they contain pectin and lethicin. What are these and how do they support gastric health?
A.Pectin is a type of water-soluble fiber commonly found in fruits such as apples and is also present in fairly high concentrations in some feed ingredients fed to horses such as beet pulp. What’s special about pectins is that when they come in to contact with acid, such as the acid in the horse’s stomach, they turn into gel. In theory, this gel could help protect the lining of the horse’s stomach from ulceration especially the glandular region (back of the stomach that attaches to the small intestine) where acid is secreted.
Lecithins are mixtures of phospholipids that are abundant in plant cell membranes. Most commonly lecithin is isolated from soybeans. Cell membranes are made up of phospholipids, which are composed of a glycerol head that attracts water (is hydrophilic) and a tail made up of two fatty acids that repel water (are hydrophobic).
Research in other species has shown that surface-active phospholipids exist in the gastric fluid and the glycerol heads can attach to the lining of the stomach. This leaves the water repelling tails pointing in towards the stomach contents, essentially creating a barrier against stomach acid. It’s therefore possible that lecithin could help stabilize the cell membranes of the cells lining the horse’s stomach, making them more resistant to ulceration or potentially helping heal them from existing ulcers by protecting them from further gastric acid assault.
Pectin and lecithin are often complexed together and added to gastric supplements with the goal of reducing ulcer formation or helping to heal already existing areas of ulceration.
Pectin-Lecithin Complex Research in Equids
Researchers have conducted several studies in horses to test the aforementioned hypotheses and found mixed results.
In one study researchers fed a pectin-lecithin complex for five weeks with a period of alternating feed deprivation to induce ulceration during the fifth week. In another study scientists fed ponies a pectin-lecithin complex for a week and then went put the ponies through 72 hours of alternating feed deprivation. In both studies the horses and ponies were gastro-scoped to see whether or not the treatment had reduced incidences or severity of ulcers resulting from the feed deprivation when compared to untreated controls. In both studies the treatment failed to prevent or minimize the risk of gastric ulceration to the squamous mucosa (found in the front of the stomach, an area typically less acidic).
Other studies looking at the ability of a pectin-lecithin complex to treat existing ulcers had more favorable results. Horses with existing squamous and or glandular ulcers were scoped and divided into treatment groups, where they received the pectin-lecithin complex for 11 days or served as untreated controls. On reassessment researchers found the horses that received treatment had a marked reduction in gastric mucosal lesions or disappearance of lesions in both regions while the untreated horses showed no improvement. Similar findings were seen in another study that looked at the ability of a pectin-lecithin complex to treat 10 Standardbreds with gastric ulcers. However, this study had no controls.
Another possible mode of action for pectin-lecithin complexes is as a buffer or to stimulate the naturally occurring production of mucus. Research has shown that this complex can significantly increase pH, but this benefit is short lived with pH returning to original levels after only 15 minutes. However, the stimulation of mucus production was significant and remained elevated for a period of six hours.
Increased mucus production could prove important when administering non-steroidal anti-inflammatory drugs (NSAIDs). These medications can erode the mucus layer in the glandular region of the stomach, increasing the horses’ risks of developing glandular ulcers. Stimulating mucus secretion might offer some added protection when NSAIDs are being used; however, this requires further investigation.
While research in to the protective properties of pectin-lecithin complexes on gastric mucosa is far from conclusive, it does appear that they might help horses with existing ulcers. However, I have a couple of important observations: First, the studies were administering about 250-300 grams of pectin-lecithin complex per day, which is significantly more than the amount found in many commercial supplements. Secondly, it’s important to recognize that in none of the research studies did administration of a pectin-lecithin complex heal all of a horse’s ulcers. Therefore, while these ingredients might provide additional support to your horse’s gastric health, they’re not recommended as substitutes for currently approved treatment protocols.