Gundry makes a lot of claims about what his diet can do for your health, including reducing gas and bloating, boosting energy, improving mood, reducing your chances of getting sick, healing your gut, and helping with weight loss.
However, there is very limited research in humans on the amount of active lectins consumed in their diet and the long-term health effects.Studies have also shown that lectins play important cellular and biological functions, and could have potential benefits in the treatment or prevention of viruses like the flu.
Specifically, Derocha says that there’s no evidence that eliminating a certain food can clean your gut, though avoiding lectins has the potential to benefit certain people.
“Lectins are proteins that can stick to cell membranes in the digestive tract, so people with gastrointestinal issues or chronic conditions like colitis or Crohn’s disease may benefit from avoiding them,” says Derocha. “When eaten in large quantities, lectins can disrupt the digestive process, due to the sticky nature of the proteins and their impact.”
Remember though, there are many caveats.
First, some experts point out that there’s little hard evidence supporting the notion that lectins are toxic or harmful to eat, especially when cooked. Not to mention, people rarely eat many of the foods potent in lectins (beans, lentils) raw, when lectin levels are highest.
Many foods that contain lectins are also packed with prebiotics, a type of fiber that can feed healthy gut flora. Therefore, avoiding these can lead to constipation and poor gut health, says Derocha.
In reality, many unknowns about lectins exist, and Gundry’s book doesn’t present an open-and-shut case.
“While there is not enough research to fully show the pros or cons of a lectin-free diet or the amount of lectin that could make a difference, there is some concern about lectins due to the potential impact of how it affects absorption of some nutrients,” says Derocha. “[High levels of] lectins are known to cluster red blood cells, which carry oxygen throughout the body. If red blood cells cluster due to excess lectin — again, the amount of lectin that’s considered harmful is unknown — we may be at risk of organs and muscles not getting enough oxygen to work as efficiently as they could.”
Lectins may specifically affect how your body absorbs minerals like calcium, iron, phosphorus, and zinc, Derocha says. This means that lectins are considered “anti-nutrients,” she says, though this may be more of a concern for people at risk of diseases related to mineral deficiencies, such as osteoporosis with calcium deficiency or anemia with iron deficiency.