What is Lectin?

Lectins are a family of proteins found in almost all foods but found in the highest concentrations in legumes and grains.  Humans have problems digesting lectins and are highly resistant to your body’s digestive enzymes. These foods are some of the highest sources of lectins in the American diet:

1.     Legumes – peanuts, garbanzo beans, kidney beans, lima beans, peas

2.     Wheat germ – contains 300 mcg of wheat lectin/gram (about ¼ teaspoon)

3.     Soybeans/soy-based products– inhibit the absorption of nutrients, especially iron

4.     Nightshade family of vegetables — white potato, peppers, tomato, eggplant  

In most cases, cooking these foods with “wet” heat, such as stewing, boiling, or cooking in sauce, breaks down lectins to minimal levels.

Some Conditions Linked to Lectins

Celiac disease: Wheat gliadin contains a lectin-like substance that binds to human intestinal mucosa. This has been debated for over 20 years as the “celiac disease toxin.” But because celiac disease is already managed by gluten avoidance, little would change if the wheat-lectin hypothesis proved to be correct.

Kidney nephropathy: Wheat lectin binds to glomerular capillary walls and tubules in human kidneys, resulting in the formation of the autoimmune antibody (IgA), which, in turn, induces fibrous deposits. This suggests nephropathy (renal disease) may be caused or aggravated by wheat.

Peptic ulcer: Lectins cause a release of histamine from stomach mast cells, which in turn stimulates acid secretion. The three main pathogenic causes for an ulcer— 1) acid stimulation, 2) breakdown of the mucous defense layer, and 3) abnormal bacterial overgrowth (Helicobacter pylori) can all be linked to various lectins. 

Inflammatory bowel disease: This incorporates two intestinal conditions: Crohn’s disease and ulcerative colitis. These conditions are thought to be made worse by gooey food lectins and genetically modified foods, including corn, canola, soy, and sugar beets. The inflammation may actually be due to traces of glyphosate remaining in the food.

Leaky gut, also known as intestinal permeability, is sometimes included as part of the inflammatory bowel disease profile. Leaky gut can be caused by undigested lectins, causing the tight junctions between the cells of the GI tract to separate, allowing the entrance of larger food particles, bacteria, and bacterial components into the systemic circulation. The result can be food allergies and a variety of autoimmune responses.