By naturopath Margaret Jasinska

Lectins are a type of protein found in almost all foods. They are especially abundant in grains and legumes. Research suggests in some people lectins can increase intestinal permeability, causing a leaky gut. In this way they can initiate or aggravate autoimmune disease.

Lectins are a way plants protect themselves from attack by pests or predators. They are a plant’s natural defence molecules. In nature, every living thing is just trying to survive. Because plants can’t run away from a predator, they increase their chances of survival by producing toxins. The toxins are usually most concentrated in the seed of the grain, which is the part that people eat. Lectins are present in most foods, but the types of lectins found in grains can be harmful to the intestines. Two particularly problematic lectins are prolamins (gluten is an example) and agglutinins (such as wheat germ agglutinin). Prolamins are very difficult for the human body to digest. Gluten is comprised of gliadins and glutenins. The human body actually cannot digest gluten. We don’t make the enzymes necessary for breaking it apart. This is a problem because it means gluten can cross the intestinal lining intact, or partially digested.

Lectins can either damage and kill the cells that line your intestines (called enterocytes) or cause spaces to open up between your intestinal cells.  The resultant little holes in your intestines allow wastes and toxins to leak into your bloodstream; then you can develop a leaky gut. Recent research is showing that gluten seems to trigger the release of zonulin in people with autoimmune disease. Zonulin causes the gap junctions between intestinal cells to open up, creating a leaky gut. This was once thought to only apply to people with coeliac disease, but research is uncovering the phenomenon in more and more autoimmune and inflammatory conditions. Asthma and rheumatoid arthritis are examples.

Along with peanuts, which are legumes, lectins are also found in nightshade vegetables. These include tomatoes, eggplant, capsicum, potatoes, chilli and paprika. People with autoimmune joint disease may experience an aggravation in their pain from those vegetables. Doing a one month elimination diet is a good way to check if they adversely affect you.