Quercetin: A Supplement for IBS?

I belong to a listserv, where dietitians exchange information on how to treat certain illnesses. Recently, quercetin was recommended a few times as a treatment for irritable bowel syndrome (IBS). I’d never heard of this use for quercetin before, so I did some research on it.

I knew that quercetin, a plant-based bioflavonoid with powerful anti-inflammatory properties, is often helpful for inhalant allergies. It inhibits the manufacture and release of histamine and other allergic and inflammatory mediators — the biochemicals that cause a runny nose, watery eyes, hives and swelling. These biochemicals are released from mast cells and basophils, immune cells that guard the mucous membranes of the respiratory system. But what does that have to do with IBS?

Well, it turns out that some IBS sufferers are actually having an allergic reaction in their guts to certain foods. There’s even a name for it: gastric-mediated allergy. And it involves mast cells, which are found in both the small intestines and the colon. When triggered by a food allergy, these intestinal mast cells release histamine into your intestines just like they do into your nose.

Histamine increases the permeability of capillaries. It makes these tiny blood vessels “leaky,” releasing fluids, white blood cells and proteins involved in inflammation. In your intestines, histamine release may be involved in a condition called leaky gut, which has been implicated as a cause of allergies, autoimmune disorders and body-wide inflammation.

More people may have this allergic type of IBS condition than commonly realized. In one study, 34 out of 44 people with IBS had more mast cell infiltration of their colon and histamine release than people without IBS. And people with IBS are about twice as likely to have other allergy symptoms, such as allergic rhinitis or eczema. It’s nice to know there’s something natural that can help all those symptoms — quercetin.

For allergies and general anti-inflammatory benefits, 250 – 600 mg of quercetin a day, in divided doses, has been proven effective. Quercetin can also boost exercise endurance by increasing cellular metabolism. (It helps muscle cells increase their numbers of energy-producing mitochondria!)

The Anti-Aging Bottom Line: An explosion of new research on quercetin has shown that it has a number of previously unknown potential uses. It’s worth consideing adding quercetin to your supplements regimen if you have IBS, or if you feel like you could benefit in any way from its anti-inflammatory, anti-allergenic, immune-strengthening or antioxidant properties.