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lectin rich foods • what you need to know

With the release of Dr. Steven Gundry’s latest book, The Plant Paradox, [and now his newest book, The Longevity Paradox] a new “villain” has emerged on the food scene. Enter, the LECTIN.




Lectins are nothing new. They are a type of protein found in the foods we eat. It is thought that lectins evolved as part of a plant’s natural defense system, helping to discourage animals from eating them. However, lectins aren’t just limited to plants since we find them in animal products as well. In your body, lectins can bind to specific sugar molecules located in our nerves, gut lining and our blood which Dr. Gundry claims causes them to interfere with the ability of our immune system to communicate with cells, wreaking havoc on our health.

Lectins in plants are a defense against microorganisms, pests, and insects. But may also have evolved as a way for seeds to remain intact as they passed through animals’ digestive systems, for later dispersal. Lectins are resistant to human digestion and they enter the blood unchanged.

Foods that are high in lectins include grains, beans, legumes including corn, soy and peanuts, wheat, potatoes, and tomatoes. They are also found in dairy products and other seeded vegetables.

While Dr. Gundry has the propensity to make polarizing statements [and push quite a few products along the way] he has quite a bit of street cred and some science to back up his claims.




Ingesting lectins poses a “challenge” to your digestion and your immune system.

  • Lectins and your digestion: This GI distress happens because lectins can damage the intestinal lining. As lectin rich food passes through the gut, it causes very minor damage to the lining of the GI tract. Normally, the cells repair the damage quickly. However, lectins have the capacity to blunt this speedy reconstruction. Our cells can’t regenerate as fast as they need to in order to keep the intestinal lining secure. Thus, our natural gut defenses are compromised after the damage occurs and over time the gut can become “leaky,” allowing various molecules [including “invaders”] to pass back and forth amid the gut wall. We may also not absorb other important things, such as vitamins and minerals, properly. When enough lectins are consumed, it can signal our body to evacuate the GI’s contents. This means cramping or urgency while exercising or worse… chronic diarrhea. Unfortunately, this will feel confusing to your body since the more plants you eat [lectin-rich of course] the worse your symptoms appear.

  • Lectins and the immune system: When lectins negatively impact the gut wall, it may also cause a broader immune system response since the body’s defenses move in to attack the invaders. Symptoms can include skin rashes, joint pain, and general inflammation. Here’s the good news: the effects of dietary lectins only extend for as long as they are in the body, and the effects can be reduced by eating a variety of fruits, vegetables in moderate amounts as well as by ingesting foods with beneficial bacteria [i.e fermented foods].




While I remain cautious around using the word “never” with food, there are some lectins that no one should ever consume. Ricin, a lectin from the castor oil plant is so toxic, it can actually kill you! Same with phytohaemagglutinin – a lectin in sprouted red kidney beans The poisoning is usually caused by the ingestion of raw, soaked kidney beans. As few as four or five raw beans can trigger symptoms. Raw kidney beans contain from 20,000 to 70,000 lectin units, while fully cooked beans usually contain between 200 and 400 units.




It begins with preparation mechanisms. By sprouting, soaking, cooking and or fermenting lectin-rich foods [with the exception to kidney beans and castor oil] you can deactivate or decrease lectin content.

  • Sprouting- Generally, the longer the duration of sprouting, the more lectins are deactivated. The lectins in some grains and beans are in the seed coat. As it germinates, the coat is metabolized – eliminating lectins.

  • Soaking and cooking- Soak beans and legumes overnight, and change the water often. Drain and rinse again before cooking. Adding a tiny splash of apple cider vinegar to the soaking water may help neutralize the lectins further.

  • Fermenting- Fermentation allows beneficial bacteria to digest and convert many of the harmful substances. No wonder some of the healthiest populations adhere to fermented soy products like miso, tempeh, tamari and natto. Cultures with a history of grain eating traditionally have used some form of fermentation to treat grains. If you’ve had sourdough bread or beer, you’ve had fermented grains.




So clearly we should avoid all lectins like the plague, right? Well Dr. Gundry would answer that with a resounding YES; however, I’m not so sure. Lectins can be neutralized by how you prepare these foods prior to eating. It’s why you can’t eat raw kidney beans, but they’re just fine cooked.

My sage advice is this… invest the time into sprouting, soaking, cooking and fermenting lectin-rich foods. Your great grandmother would be proud. And you just might find some of those sneaky symptoms of digestive distress loosen their grip on you.

Since lectins are so widely distributed in foods commonly consumed [many of which are vegetables] and have have been safely consumed for centuries, there is no reason to remain “fearful” around these foods. Instead take note of which foods contain more lectins than others and do the work necessary to allow your body access to the nutrients within. After all food is just “information” to the body. And by decreasing lectins you increase your body’s utilization of food’s message.

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  • Gundry, S. (2017, May 23). 15 Ways to Reduce Lectins in Your Diet. Retrieved from

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