Could Plant Lectins Be Hurting Your Gut? A Doctor Explains

You might not hear much about lectins these days. There is limited research on how these plant proteins affect people, but those with digestive issues might want to pay close attention. (To read more about the lectin-free diet, check out our full explainer here.)

Of course, humans have been eating plants since the dawn of time (less so with seeds, however). As a result, humans have developed a natural protection against lectins. The lining of the gut is coated with a protective barrier of carbohydrate molecules, or mucus. These molecules act like decoys that neutralize the plant lectins. Even so, high concentrations of lectins can still cause a lot of damage to people with food sensitivities

Both lectin proteins and gluten proteins have the potential to damage the gut lining, but they're not the same. Lectin proteins are found in the outer protective covering of the seed, called bran. Whole-grain products are actually high in lectins.

Gluten is a plant storage protein found in the seed's endosperm; it stores amino acids necessary for the seed to sprout. Because plant storage proteins are structured differently from animal proteins, they can be hard to digest and can irritate the intestinal tract of animals. While all seeds contain storage proteins, gluten proteins can be the most irritating.

While lectins and gluten are distinct, our approach to them is somewhat similar. Just as how you would avoid gluten if you're gluten intolerant, you might want to avoid lectins if you think you might have a sensitivity. On the other hand, if you can tolerate lectins just fine, there's no reason to steer clear—just as someone who isn't gluten intolerant might incorporate gluten into their lifestyle.

Fish, eggs, and poultry don't contain lectins, so they're the best source of protein for a lectin-free lifestyle (red meat is a bit harder to digest).

Lectins can be reduced (but not eliminated) in grains by sprouting and boiling. Baking, however, doesn't significantly reduce the amount of lectins or gluten in wheat products.

Lectins can be reduced in beans by extended soaking, fermenting, or prolonged boiling (raw and/or sprouted kidney beans are actually poisonous because of their high lectin content). Fermented soybean products, such as tempeh, are lower in lectins than other soy products.

Fortunately, there is an exception to every rule: white rice. The lectins and storage proteins in white rice have a lower potential for harm. The carbohydrates in rice are broken down completely and typically don't contribute to bacterial overgrowth in the gut.