What Are Lectins and Should I Be Worried About Them?

Lectins are a type of protein, known as a “glycoprotein,” that can bind to carbohydrates and are found in plants. They are particularly high in foods like raw lentils, kidney beans, soybeans, and certain grains. Lectins are often referred to as “anti-nutrients” due to their ability to interfere with the absorption of certain nutrients. 

The main concern surrounding lectins stems from their resistance to digestive enzymes in the gut, which makes them difficult for the body to break down. When consumed in significant amounts, active lectins can cause gastrointestinal side effects, such as nausea, vomiting, diarrhea, and abdominal pain. In their active state, lectins can also interact with intestinal cells, potentially affecting intestinal permeability.

Should I Be Worried About Consuming Lectin Foods?

It’s important to note that consuming foods high in lectins is quite rare, as lectins in their active state are primarily found in uncooked legumes and grains,—foods we typically don’t eat raw. Cooking these foods renders lectins inactive, which makes them safe to consume. In fact, when legumes are boiled for one hour, 93.8-99.8% of lectins are deactivated. Studies have shown that boiling red and white kidney beans, for example, completely eliminates lectins (known as phytohaemagglutinin. Other methods, such as autoclaving, fermenting, soaking, and sprouting, also significantly reduce lectin content. As long as your food is properly cooked, there’s no need to worry about lectins. (And yes, canned beans are cooked!)

Do Lectins Have Any Benefits?

Some people avoid “lectin foods” out of concern, but it’s important to remember that foods containing high lectins, such as beans, are also packed with essential nutrients. These foods are rich in vitamins, minerals, fiber, essential amino acids, and antioxidants. The health benefits from these nutrients far outweigh any concern about lectins—especially since properly cooking legumes renders lectins inactive. 

Researchers are also exploring how lectins could be used in pharmaceuticals. Some clinical studies have examined their potential as anti-tumor, anti-diabetic, anti-microbial, and anti-viral agents. For instance, a study on lectins from legumes showed antifungal activity against Candida albicans, a fungus found in the body that can cause infection when it overgrows.

TL;DR

Lectins are anti-nutrients found mainly in raw legumes. While they can cause gastrointestinal side effects in their active state, lectins are easily deactivated by cooking, fermenting, soaking, and sprouting. Unless you’re consuming raw legumes or grains, there’s no need to worry about lectins in your diet.