What You ACTUALLY Need to Know About Lectins (What RESEARCH Shows)

Dr. Stengler: In this video, you're going to learn about the controversial plant compounds called lectins, the concerns they raise, how to safely prepare lectin-containing foods, and their surprising potential health benefits. I'm Dr. Mark Stengler, and I've researched and written 20 books on nutrition and functional medicine.

What are lectins? We're all encouraged to eat more plant foods, as plant-based diets have been shown to reduce the risk of several chronic diseases. But in recent years, there's been some discussion about the so-called anti-nutrients in plants, and one of the most controversial groups is lectins. As defined in the journal Nutrients, lectins are carbohydrate-binding proteins found in both plants and animals. In plants, their job is to provide protection against invaders like insects, molds, and fungi. You'll find the highest concentration of lectins in raw legumes and whole grains, with smaller amounts in nuts, seeds, fruits, and vegetables.

So the question is, are lectins harmful? There are a few theoretical concerns about eating plant lectins, discussed in another journal called the Journal of Functional Foods. First, lectins are highly resistant to being broken down by our digestive enzymes. This could potentially disrupt the intestinal lining, leading to increased gut permeability, also known as leaky gut — and I've had many videos on this topic — and activation of the immune system. It's important to note, however, that research showing this kind of harm has been done in animal models using high doses of isolated lectins. Second, lectins can cause the clumping of red blood cells and may also block nutrient absorption. There's some concern about a potential link to autoimmunity: a study in the Journal of Immunology Research looked at 500 healthy adults and found lectin-specific antibodies in up to 15% of blood samples, which suggests lectins can pass through the intestinal wall. The study found a correlation between certain anti-lectin antibodies and rheumatoid factor. This suggests lectins may play a role in autoimmunity, but more research is needed before we make any definite conclusions, because it's so preliminary.

The good news is that lectins are denatured and deactivated through common cooking methods. There have been cases of food poisoning from eating raw or inadequately cooked legumes like kidney beans, which is why proper preparation is so important. Effective methods for deactivating lectins include soaking, fermentation, autoclaving, and boiling. Interestingly, as reported in the journal Foods, recommendations for cooking beans aren't uniform. For example, the World Health Organization recommends soaking beans for at least 12 hours followed by 10 minutes of vigorous boiling; the FDA recommends soaking for 5 hours followed by 30 minutes of cooking; and Danish authorities, who are experts in this area, recommend 10 to 12 hours of soaking followed by 30 to 60 minutes of boiling. So if you tend to have problems with legumes, I would go with the higher cooking time to deactivate those lectins.

But there are surprising benefits of lectins a lot of researchers won't tell you. While they protect plants, research reported in the Journal of Functional Foods suggests that lectins may also have human health benefits, including cancer protection due to an anti-tumor effect. Additionally, lectins from legumes have been shown to have antimicrobial activity against Candida albicans, bacteria, and viruses. However, more human research is needed in this area. So while lectins are a valid concern in raw or undercooked foods, proper cooking methods effectively neutralize them, and far from being just an anti-nutrient, they may even offer some unique health benefits. I hope this video cleared up the controversy around lectins. If you found it helpful, please hit the like button and subscribe. Thanks for watching.

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