Potatoes Increase Intestinal Permeability in Inflammatory Bowel Disorders

Evidence suggests that inflammatory bowel disorders such as Crohn's disease and Ulcerative colitis may be aggravated by the consumption of potatoes. These inflammatory disorders cause ulceration and inflammation in the intestines, as well as a host of potential systemic and extraintestinal symptoms. In addition, individuals with Crohn's disease and Ulcerative colitis are known to have increased intestinal permeability.

The increased intestinal permeability of people with IBD occurs as a result of a particular genetic predisposition and is involved in both initiating and perpetuating the chronic inflammation of these disorders. In addition, research is beginning to elucidate other factors that worsen the intestinal permeability in IBD. A study published in Digestive Diseases and Sciences confirms the results of a previous study published in the journal Inflammatory Bowel Disorders: potato glycoalkaloids adversely affect intestinal permeability.

Glycoalkaloids, such as solanine and chaconine, are natural compounds found in all potatoes. These glycoalkaloids are poisons that the potato plant produces in self-defense. Glycoalkaloids protect the potato from certain pathogens such as fungi, bacteria, and parasites. The glycoalkaloid poisons of potato are concentrated in the leaves, stems, potato skin, and approximately 1.5mm of potato flesh beneath the potato skin.

Glycoalkaloids create the bitter taste of raw potatoes and are commonly found in other members of the deadly nightshade family. Specifically, these potato poisons appear to affect the integrity of the mucosal barrier of the intestinal lumen. The glycoalkaloids accomplish this by permeabilizing cholesterol-containing membranes.

The concentration in most strains of potatoes that are consumed through out the world is below a predetermined limit at which glycoalkaloid produce severe toxicity symptoms. At high levels, glycoalkaloids can actually cause systemic toxic effects such as injury to the gastrointestinal tract resulting in vomiting and diarrhea, tachycardia, hemolysis, headache, and potentially even neurotoxicity with subsequent death.

It appears that the method used to prepare potatoes for eating can affect the concentration of toxic glycoalkaloids in the potato. Studies have determined that frying potatoes will concentrate the glycoalkaloids. In support of this interesting information on fried potatoes, epidemiological studies have shown that the prevalence of IBD is highest in countries where the consumption of fried potatoes is highest. Additionally, the glycoalkaloid content within the potato increases with exposure to light, physical damage, a high temperature storage, and with age.

Inflammatory bowel disorders, such as Crohn's disease and Ulcerative colitis, are associated with altered intestinal permeability and significant inflammation. Evidence is accumulating to show that dietary factors, such as glycoalkaloids in potatoes, may negatively affect intestinal permeability and worsen IBD.

Sources:

Iablokov V, et al.

Naturally Occurring Glycoalkaloids in Potatoes Aggravate Intestinal Inflammation in Two Mouse Models of Inflammatory Bowel Disease. Dig Dis Sci. 2010 Mar 3.

Patel B, et al. Potato glycoalkaloids adversely affect intestinal permeability and aggravate inflammatory bowel disease. Inflamm Bowel Dis. 2002 Sep;8(5):340-6.