Lectins are proteins that bind to carbohydrates. They are found mainly in legumes and grains. Some lectins are harmless; others, such as those in kidney beans, can cause digestive symptoms if not cooked properly.

Lectins can also negatively affect people who have digestive sensitivities or gastrointestinal distress. The reason for this is that lectins may interfere with both the gut microbiota and the absorption of nutrients.

In addition, lectins may decrease acid secretion and increase inflammation.

They are present in most plant foods but are especially high in:

• Grains such as barley, quinoa, and rice

• Legumes such as beans, lentils, peas, soybeans, and peanuts

• Nightshade vegetables such as tomatoes, eggplant, potatoes, and peppers

For many foods containing harmful lectins — such as kidney beans — cooking greatly reduces their lectin content, making them safe to eat. It’s a good idea to boil beans for 30 minutes to eliminate their lectins. Soaking beans also reduces their lectin content, though perhaps not enough to ensure safety.

Foods that contain lectins are often full of antioxidants, vitamins, and minerals that are good for you.

If you are not lectin-sensitive, these benefits will likely outweigh the negative effects of lectins to the body. If you are allergic or have food sensitivities, however, I recommend reducing the lectins in your diet or eliminating them entirely.