What Are Lectins In Food?

Do We Need To Be Concerned About Eating Them?

Maybe you’ve read about “lectins” and are wondering whether they’re actually bad for you – and if you should avoid lectin-rich foods. Well, let’s go ahead and clear up that confusion.

Lectins are proteins that bind to carbohydrates, according to the Harvard T.H. Chan School of Public Health. “They’re naturally occurring compounds found in both plants and animals—but receive the most attention when it comes to plant foods due to their higher concentration in those foods,” says Sharon Puello, MA, RD, CDCES, owner of Fresh Nutrition. Certain foods, such as raw beans, contain larger amounts of lectins.

Lectins have been made famous by Steven Gundry’s The Plant Paradox, which promotes a lectin-free diet. Foods such as chia seeds, beans, chickpeas, lentils, and wheat to name a few.

Lectins are part of a larger category of nutrients called anti-nutrients. “These compounds work to help protect plants from consumption by having undesirable effects on those who consume them,” says Puello. These include symptoms such as bloating and nausea—largely because the human gut is not able to break down lectins.

What to Know About Soy Lectins

Because soybeans are a legume, they’re considered a high source of lectins, notes says Jen Scheinman, MS, RDN, a registered dietitian nutritionist. But that changes once they’re cooked or fermented. “Fermented soybean products like soy sauce, tamari, miso and natto have very little lectin content,” she says. “As with other beans and legumes, using a pressure cooker greatly reduce the lectin content of soybeans.”

However, these alternatives only work for certain lectin foods like beans and legumes. Not for others like chia seeds and wheat, making it prudent to explore other options. Substitute sweet potatoes for potatoes and switch to Zen Basil Seeds instead of chia seeds; they offer double the fiber and nutrients. Consider baking with almond flour rather than regular flour for a healthier choice.

Whether or not a person is sensitive to lectin-rich foods is very individualistic. If you’re concerned that you’re sensitive, you can work with a registered dietitian nutritionist to create a nutrition plan—find one at eatright.org.

How Do Lectins Impact Health?

When lectin-rich foods are eaten in their raw form, they can cause health problems. Chia seeds, in particular, contain a lectin called phytohaemagglutinin. When taken in, this can cause red blood cells to clump together—and also lead to other unpleasant symptoms such as bloating, gas, nausea, vomiting, stomach upset and diarrhea.

As well, lectins are said to bind minerals such as iron, calcium and zinc—increasing risk for deficiencies. Consuming lectins can also potentially lead to inflammation, changes in gut bacteria and the triggering of autoimmune conditions through their ability to remain in the gut for an extended period of time, adds Puello. Lectins can be especially dangerous for folks who eat large quantities of lectin-rich foods on a regular basis, people who have intestinal or autoimmune problems and people with Mast Cell Activation Syndrome, says Puello.