Dietitian Dish: Lectins: The New Bad Guy in Your Diet?

December 05, 2018

By Saba Zahid, RD
Patient Experience Manager, Unidine Corporation

Gather around folks – it’s time for another mythical big bad food/ingredient/fad diet story. If you haven’t already heard, there is supposedly a new bad guy in the world of food, diets, and weight – lectins. Singer Kelly Clarkson has propelled lectins into the limelight with her claims that a lectin-free diet was responsible for her weight loss as well as curing her thyroid issue. So let’s give lectins a closer look and explore the science behind the claims.

In an interview earlier this year with NBC’s Today Show, Kelly Clarkson referred to a book she read, leading her to a lectin-free diet. The book Clarkson refers to is “The Plant Paradox,” written by Dr. Steven Gundry. In his book, Gundry claims that lectins- a broad group of plant proteins found in grains; beans and legumes; nuts; fruits; dairy; and nightshade vegetables such as eggplant, tomatoes, and potatoes - are making us sick. According to Gundry, lectins are supposed to act as a defense mechanism to protect the plants that they originate in and when we ingest these lectin containing plants, the lectins “incite a kind of chemical warfare in our body,” resulting in many of today’s illnesses from obesity, digestive issues, autoimmune disorders to arthritis, adult acne, and brain fog.

So the obvious conclusion from the information Dr. Gundry provides-lectin-free is the way to go. But many doctors and dietitians disagree with the recommendation. Eliminating lectin-containing foods flies in the face of nutrition recommendations by reliable organizations such as the American Heart Association and the American Cancer Society. Additionally, some of the healthiest populations around the world have diets rich in lectin-containing beans, legumes, and whole grains. Furthermore, there have been only a limited number of studies on lectins since the 1970s with inconsistent results. Most of these studies were conducted in test tubes or on animals, so translating the results of those studies to humans can be complicated and confusing.

One critical thing to point out in addition to the arguments mentioned above - lectins become deactivated during cooking, fermenting, or the sprouting processes. This is great news because people don't generally eat raw grains or lentils. There is a possible risk that not all the lectins in raw beans are broken down in the cooking process when making a casserole or using a slow cooker because the temperature may not get high enough. This particular situation may lead to lectin toxicity, causing nausea, vomiting, and diarrhea that can last for a few hours.

To be safe, be sure to soak dry beans and lentils in water for several hours. When you are ready to cook your beans/lentils, pour off the water and boil the beans/lentils in fresh water for about 10 minutes. Finish preparing the beans or lentils on the stove or the slow cooker based on your recipe. Canned beans do not present a concern because they are already cooked.

As long as you remember, no one secret food, ingredient, or compound is the answer to all of our health and weight issues. It all comes down to a lifestyle of healthy eating that includes a variety of different foods.

Need help navigating a healthy eating plan or have other diet related questions? Why not try working with one of Shore Medical Center’s Outpatient Nutrition Counseling dietitians. We would love to help you improve your health through diet. To schedule an appointment, contact us at 609-653-4600, option 5. To learn more, visit our website at