They’ve become the dietary demon du jour: Lectins — a type of protein found in many foods but especially prominent in grains and beans — are being blamed for a variety of health problems, from digestive distress and skin irritations to brain fog, chronic fatigue and inflammation. In his recent book “The Plant Paradox,” Dr. Steven Gundry refers to lectins as “edible enemies,” partly because they help plants defend themselves from insects and other animals, but also because lectins bind to carbohydrates (especially sugars) in the body, “which means they can interrupt messaging between cells or otherwise cause toxic or inflammatory reactions.”
That’s an alarming statement, indeed. But when it comes to human health, are lectins really as harmful as Gundry and some other experts make them out to be? The answer is: Not necessarily, but the issue is complicated. Lectins are “often considered antinutrients because of their ability to bind to sugar and other carbohydrate molecules, [and because] lectins are resistant to human digestion, it’s believed that they interfere with the proper absorption of vitamins, minerals and some key proteins,” says Dr. Frank Lipman, founder of the Eleven Eleven Wellness Center in New York City and author of “The New Health Rules.” “The concern is that when we eat foods that are high in lectins, we’re not getting the full benefit of the nutrients we eat.”
[See: What All Plant-Based Eaters Need to Know About Vitamin B12.]
There’s another potential concern: Because lectins tend to be clingy in the gastrointestinal tract and can attach to the intestinal wall, problems can arise if the lining of your intestines isn’t healthy. Simply put, the lining can become more permeable, allowing food particles such as lectins to slip into the bloodstream, which can trigger an inflammatory response and/or the production of antibodies to lectin. “For those who eat a lot of raw, lectin-rich foods — vegetarians or those following a plant-rich diet, for example — the higher lectin intake and the resulting gastrointestinal distress like nausea, diarrhea and bloating can weaken the delicate gut lining, triggering leaky gut syndrome, system-wide inflammation and autoimmune or allergic reactions,” Lipman says.
Sorting Through the Risk-Benefit Ratio
For many people, however, some health experts believe the hullabaloo over lectins is overblown. “Lectins are far more active in binding to our cells when they’re consumed in high concentrations and in isolation, as they are in experiments, than when they are consumed in food, as they generally are by actual humans,” notes Dr. David Katz, director of the Yale University Prevention Research Center at Griffin Hospital and founder of the True Health Initiative.
Plus, cooking vastly reduces the lectin content of many foods, which matters significantly because “no one is eating raw lentils or kidney beans,” says registered dietitian Kristin Kirkpatrick, manager of Wellness Nutrition Services at the Cleveland Clinic Wellness Institute. Besides, lectins may have some health benefits, and “they happen to be in foods that are healthy for us that we don’t eat enough of anyway,” Kirkpatrick says.
In fact, lectins in legumes have antimicrobial features and anticancer activities, according to research in a 2017 issue of the International Journal of Molecular Sciences. A study in a 2015 issue of the journal Oncotarget found that orally administering a particular plant lectin called MASL (from the seeds of the Maackia amurensis tree) may be helpful in combating oral squamous cell carcinoma, which is the most common form of oral cancer. What’s more, consuming pulses (beans, peas and lentils), which contain lectins, improves blood lipid levels, blood pressure and inflammatory markers, according to a review in a 2014 issue of Applied Physiology, Nutrition, and Metabolism; also, because pulses are high in fiber and have a low glycemic index, they may be especially helpful in regulating blood sugar levels in people who have diabetes.
[See: 7 Traditional Chinese and Indian Eating Principles That Can Help You Lose Weight.]
Should You Avoid Lectins?
While there are undoubtedly people who are sensitive to lectins, just as some people are sensitive to gluten, “saying that means lectins are toxic is like saying that peanuts or seafood are toxic because some people are allergic to them,” says Katz, who is a former U.S. News contributor. “Food sensitivities and allergies are by their very nature idiosyncratic and say nothing about the toxicity of a given compound, let alone a vast swath of the entire food supply.”
So think twice before you jump on the antilectin bandwagon. If you have chronic digestion problems (such as irritable bowel syndrome), or you’ve been diagnosed with an autoimmune condition (such as rheumatoid arthritis), talk to your physician about whether you should remove lectin-rich foods from your diet. Some people may be born with a genetic predisposition to lectin-sensitivity, “in which case they would have a more immediate allergic reaction,” Lipman says. But “usually we see lectin sensitivities develop when a patient’s gut has been compromised and is out of balance.”
If you are basically healthy and don’t have digestion woes or allergy problems but wonder if you might be sensitive to certain lectins, you could try a short-term elimination diet: Cut out legumes, beans, grains and nightshades such as eggplant, tomatoes and potatoes for four weeks, Kirkpatrick explains, “then slowly reintroduce these foods [one at a time] to see if the symptoms come back.” If they do, there’s your answer. If they don’t, you’re in the clear.
For those who can comfortably tolerate lectin-rich foods, it’s best to cook beans and legumes thoroughly before you consume them. Also, the sprouting process — for grains, beans, legumes and seeds — releases enzymes that reduce the total amount of lectins in a given food, Kirkpatrick says. “Soaking raw beans before cooking them does, too, and getting fermented bread, like sourdough, can help.”
[See: Your Plant-Based Diet Needs These 10 Foods.]
For most people, Katz says, there’s no good reason to avoid nutritious plant-based foods that are good for your health just because they contain lectins. That’s the dietary equivalent of throwing the baby out with the bathwater. “Following this advice will decimate the quality of your diet,” he says, and if you stick with it over time, it could quite possibly compromise your health.
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The Trouble With Lectins originally appeared on usnews.com
