Even though many people follow a lectin-free diet, few are apprised of the knowledge that a diet including lectins improves cardiovascular health, stimulates weight loss, and lowers the risk of type 2 diabetes. It plays an essential role in strengthening the immune system and protecting the body against invasive microorganisms. 

What are Lectins?


It is a special protein that binds the carbohydrates found in the body. They are also indigestible and cannot be broken down by the digestive system. They are commonly found in raw or undercooked beans, legumes, and whole grains. Even though they’re also found in animals, they are most commonly associated with plants and their defensive nature. [1]

People who consume them go through undesirable outcomes such as bloating or nausea since the digestive system cannot break them down. They’re termed as ‘anti-nutrients’ due to their effects on people.

Foods Rich in Lectins


Since you can find it in both plants and animals, different kinds have various side effects on the body. Not all lectins can be harmful to the body even though they pass through the digestive system unchanged. They are mainly considered bad for the body because they bind themselves to different carbohydrates, posing health risks for people. 

It can easily be found in our daily dietary requirements. Foods highest in this nutrient include: 

1. Raw kidney beans

Kidney beans contain a large amount of protein and are also categorized as a low glycemic-index food. However, they also have many of them present, which can be reduced and broken down if the beans are cooked properly. A high amount of it can lead to health complications as well. 

2. Peanuts

Peanuts are a great source of energy for the body, and it contains lectins that the body can easily absorb. However, no results have come up yet that show peanut lectins being harmful to the body. 

3. Whole grains

Raw whole grains are also a great source of lectins. Moreover, raw wheat germ can contain as much as 300mcg of lectins per gram. Raw whole grains and wheat shouldn’t be consumed if you’re trying to avoid lectins.

4. Raw soybeans

Soybeans are legumes that are rich in them too. They’re eaten after being toasted or heated, which is insufficient to break down the lectins. Raw soybeans should be avoided due to their high lectin concentration. 

5. Raw Potatoes

Potatoes also have a high level of lectins, especially in their skins. If you are avoiding it, you should cook potatoes fully and peel off the skin completely. 

Are Lectins Bad for You?

Lectins are present in many healthy foods that we consume, but certain types, such as those found in red kidney beans, should be avoided. Some are harmless, and some cause trouble in nutrient absorption, digestion, and even inflammation in the body. Rather than removing it from the diet completely, it is better to cook foods containing them fully. 

Lectins are bad for you because they stick to carbohydrates like sugars in the body. It can cause:


Since lectins can stop nutrient absorption in the body, they may lead to malnutrition when the body doesn’t absorb important nutrients like calcium, iron, phosphorus, and zinc. This can develop into a serious problem.


Some lectins don’t just cause nutritional harm but may be poisonous. Castor beans contain a poisonous lectin called ricin in them. 

Damage to the Digestive System

Some lectins can attach themselves to the walls of your gut, causing severe health problems. Phytohemagglutinin is one such lectin that can attach to the digestive system and lead to abdominal pain, vomiting, and nausea. 

Lectins and Inflammation

The link between lectins and inflammation comes down to the body’s digestive system. As it is known that they bind themselves to carbohydrates and stop nutrient absorption in the body, they can also affect the growth of intestinal flora. 

They can also attach themselves to cells for a long time, leading to an autoimmune response in the body, triggering inflammation and conditions such as rheumatoid arthritis and type 1 diabetes. These studies and effects produced by lectin consumption have triggered lectin-free diets, provoking people to stop consuming foods containing lectins.

Lectins to Avoid


Both animals and plants contain it, but they are mostly found in raw legumes, beans, and vegetables. Lectins are found in high amounts in the following:

  • Lentils
  • Soybeans
  • Peas
  • Peanuts
  • Tomatoes
  • Eggplant
  • Milk
  • Barley
  • Quinoa

It shouldn’t be removed entirely from the diet since cutting off lectin-rich foods would mean cutting down on healthy food, which is also important for nutrition. 

Red kidney beans contain lectins which are bad for the digestive tract, so it would be better to cook them thoroughly so they can be broken down easily. However, cooking peanuts may not sufficiently reduce or break down the lectin content. [2]

Benefits of Lectins


While they may sometimes be harmful to our bodies, they also have certain benefits. Since they are found mainly in plants, they have multiple nutritional benefits. Moreover, proteins found in lectin-rich foods improve cell functioning and the body’s immune response to infections. [3]

Research shows that it can treat anxiety and depression in people if more studies are conducted on this in the future. It may also contain anti-cancerous properties and antioxidants, protecting cells from radical damage. Since they slow down digestion, they can control blood sugar levels without a sudden rise in energy in the body. 

Foods with lectins have many more nutritional advantages than disadvantages. To avoid the health issues triggered by it, you can control the intake and make sure they are adequately cooked. 

Side Effects of Lectins

Consuming a large number of them can have many side effects on the body. [5] 

Some of the most common ones are:

  • Bloating
  • Joint pain
  • Fatigue
  • Constipation
  • Diarrhea 
  • Stomach discomfort 
  • Nausea
  • Vomiting 

Bottomline: Health Benefits and Risks of Lectins

When consumed in a large quantity, lectins can lead to many problems in the body. However, if they are eaten in a moderate amount and are cooked fully, then they prove to be more beneficial than harmful. Hence, one shouldn’t opt for a lectin-free diet and cut down important nutrients from the diet but should eat them safely through a moderate intake. 

Disclaimer: This article is only a guide. It does not substitute the advice given by your own healthcare professional. Before making any health-related decision, consult your healthcare professional.

Editorial References And Fact-Checking

  • Harvard T.H. Chan School Of Public Health. (2022, March 2). Lectins. The Nutrition Source. Retrieved August 29, 2022, from https://www.hsph.harvard.edu/nutritionsource/anti-nutrients/lectins/
  • Food and Drug Administration. (2022). Handbook of Foodborne Pathogenic Microorganisms and Natural Toxins. Retrieved August 29, 2022, from https://www.fda.gov/media/83271/download
  • Noah, N. D., Bender, A. E., Reaidi, G. B., & Gilbert, R. J. (1980). Food poisoning from raw red kidney beans. British medical journal281(6234), 236–237.


  • Farah Jassawalla

    Farah is a veteran writer, season journalist, and copywriting expert with over six years of professional experience in the content creation field. Her forte lies in translating medical jargon and complicated health terms into easy-to-understand language for readers who may not have a medical background. LinkedIn


Farah is a veteran writer, season journalist, and copywriting expert with over six years of professional experience in the content creation field. Her forte lies in translating medical jargon and complicated health terms into easy-to-understand language for readers who may not have a medical background. LinkedIn