Are Lectins Bad For You? Pros and Cons of Foods with Lectins

They have an essential function in our body, providing benefits or counter effects.

Although lectins are found in many highly nutritious foods, they have come under fire as a hidden source of health problems and inflammation, placing them among the list of antinutrients in foods.

Some nutrition experts claim that these seemingly harmless proteins could have damaging effects, throwing your immune system out of control and increasing your risk of chronic disease.

On the other hand, some argue that the benefits of lectin-rich foods outweigh the potential adverse health effects, noting that simple steps can be taken to minimize the lectin content in the foods you eat daily.

So what foods contain lectins? Are lectins harmful to you, or is it just an exaggeration?

What are lectins?

Lectins are a large family of proteins found throughout the food supply, but they are ubiquitous in grains and legumes.

Lectins in food bind to carbohydrates, forming glycoproteins. These glycoproteins perform many bodily functions, from regulating the immune system to keeping protein levels in the blood under control.


However, consuming too many lectins can also have adverse health effects, with some research showing that they can cause adverse symptoms, such as vomiting and diarrhea, contribute to leaky gut, and cause impaired immune function.

Fortunately, there are many ways to reduce the lectin content of your food without following a lectin-free diet or severely restricting your intake.

Some of these methods include cooking, sprouting, soaking, and fermenting foods to minimize the concentration of lectin to help promote better health.

Are all lectins harmful to you? Pros and cons

So are lectins harmful for you? While it is true that eating too many foods with lectins can cause adverse health effects, lectins also perform many vital functions within the body.

  • They regulate cell adhesion.
  • They are involved in immune function and glycoprotein synthesis.

Lectins are also involved in immune regulation, and some research indicates that they may also have antimicrobial properties. They are effective against several types of bacteria, including the strain that causes staph and E. coli infections.

Lectins can also help fight fungus and viral infections, with in vitro tests suggesting that they can help block the growth of the specific fungus responsible for fungal infections.

Not only that, but some studies also show that specific lectins might even possess anti-cancer properties.

According to a 2015 review study, plant lectins can modify the expression of specific immune cells and alter signaling pathways to help kill cancer cells and block tumor growth.

With that said, there are some definite downsides associated with consuming lectin, particularly when it comes to the connection between lectins and inflammation.

Lectins are challenging to digest, and consuming large amounts can damage the intestinal wall and lead to the leaky gut syndrome, a condition characterized by increased permeability in the gut.

This results in the leakage of substances from the intestines into the bloodstream, causing widespread inflammation throughout the body.

Lectins also act as an antinutrient, which can interfere with digestion and absorption of food, increasing the risk of nutritional deficiencies.

Furthermore, because lectins are also involved in regulating the immune system, some show that they could also play a role in autoimmune conditions, such as rheumatoid arthritis.

Autoimmune conditions result from the immune system attacking healthy cells in the body, causing symptoms such as inflammation, fatigue, and chronic pain.

Additionally, consuming too many lectins can cause more immediate adverse side effects, including digestive problems. Eating uncooked beans, for example, can cause lectin poisoning and gastroenteritis, a condition that causes symptoms such as:

Ten foods high in lectins

Healthy Lectin Foods vs. unhealthy lectin foods

So what foods are rich in lectins?

Although they are found in abundance throughout the food supply, they are ubiquitous in many types of grains and legumes. However, that does not mean you should eliminate all foods containing lectins from your diet.

Practicing proper preparation with these lectin-containing foods can lower the lectin content, allowing you to take advantage of the unique health benefits they have to offer.

10 of the best lectin foods:

  • Papas.
  • Eggplant.
  • Soy.
  • Lentils.
  • Peppers.
  • Wheat germ.
  • Red beans.
  • Peas.
  • Tomatoes.
  • Peanuts

Many lectin-rich foods, such as grains and legumes, are well suited to the Ayurvedic diet and have been used in other forms of holistic medicine, such as traditional Chinese medicine.

According to Ayurveda, legumes are considered astringent in taste, which means they are drying out. They promote elimination and regularity, suppress appetite, and satisfy the stomach.

In general, it is recommended to soak legumes before consumption, not only to reduce lectins but also to improve their nutritional value and reduce antinutrient content.

Meanwhile, in traditional Chinese medicine, most beans are believed to have a neutral effect on the balance of the body. They are also believed to decrease bloating and act as a natural diuretic to remove toxins and waste products from the body more efficiently.

Other high-lectin foods, such as tomatoes, are considered refreshing and are said to improve digestion and detoxification.

Signs of consuming too many lectins

Consuming high amounts of lectins can cause a wide range of adverse side effects and can even be linked to problems like leaky gut syndrome and certain autoimmune conditions.

Here are some of the more common symptoms that can occur with excessive lectin intake:

  • Swelling.
  • Fatigue.
  • Joint pain
  • Gases.
  • Stomach ache.
  • Vomiting
  • Diarrhea.
  • Constipation .
  • Changes in the skin

Autoimmune conditions can also be related to a high intake of lectins. If you suffer from conditions such as rheumatoid arthritis, lupus, or inflammatory bowel disorder, reducing your lectin intake by thoroughly cooking your food can help improve symptoms.

Lectins vs. Leptinas

Although only one letter differentiates lectins from leptins, there are other differences between the two. While lectins are a type of protein that binds to carbohydrates, leptin is a hormone found in your body.

Leptin is often called the “starvation hormone” because it is produced by fat cells and sends a signal to your brain when you have had enough to eat.

It is believed to play a role in energy balance and weight management, and research on this topic shows that leptin resistance may alter the function of this hormone and may be linked to obesity and weight gain.

How to Eliminate or Limit Lectins from Food

Although lectins have been associated with several adverse side effects, there is no need to eliminate lectin-rich foods from your diet.

With proper preparation, you can quickly reduce the lectin content of your foods, making it easy to incorporate a large number of foods high in polyphenols and low in lectins in your diet.

Cooking the legumes

In this particular way, almost all lectins can be removed.

A major study by the Division of Nutritional Sciences of the Research Institute in Scotland shows that soybeans can virtually eliminate all of the lectin action when boiled for as little as five minutes.

Because legumes are generally cooked and not raw, most legumes in your diet have very few lectins.

Soak and germinate grains and seeds

Soaking and sprouting grains and seeds can also be an effective method of reducing lectin content.

Sprouting, also known as germination, is a process that involves soaking the seeds for up to 24 hours and then repeatedly rinsing and draining them every several hours for several days at a time.

Sprouting not only lowers the lectin content of grains and legumes but can also improve the nutritional profile of foods and reduce the number of other antinutrients that interfere with digestion.

Fermenting your food

The fermentation technique can also help reduce the amount of lectin content. Fermentation allows beneficial bacteria to digest lectins and other antinutrients in food to improve the overall nutritional profile.

This is demonstrated in research published in Food Science and Nutrition (FSN, Food, Science & Nutrition). Additionally, fermentation also provides valuable probiotics to your diet to give a vigorous boost to gut health.

Using the pressure cooker may be your best option when it comes to removing lectins from tomatoes or potatoes. Add water, cover the utensil carefully and correctly, and start cooking.


Lectins were first discovered in plants more than 100 years ago. Microbiologist Peter Hermann Stillmark is credited with establishing the description of the oldest lectins in 1888.

For his doctoral thesis at Dorpat University, he presented his findings from an experiment in which he isolated ricin, a type of toxic lectin found in beans.

In the years that followed, scientists began understanding the role lectins play in diet and nature.

They also began to attract more attention as some health professionals began to point to them as contributors to hidden health problems.

Dr. Steven Gundry, for example, is a cardiac surgeon and a well-known proponent of the plant-based diet.

In 2017, Gundry published a book entitled “The Plant Paradox: The Hidden Dangers in Healthy Foods That Cause Disease and Weight Gain”; This study explored the health effects of lectins and explained which foods to avoid in your diet.

While it is true that consuming too many lectins can have some negative consequences, most health experts agree that most lectin-rich foods are also rich in essential nutrients.

However, they should be of little concern when appropriately cooked and combined with a healthy diet.


Although lectins have been associated with several negative effects and adverse symptoms, they are generally found in nutrient-dense foods that provide essential vitamins and minerals to promote better health.

Rather than eliminate lectin-rich foods from your diet, it is best to work to reduce lectin content by cooking, sprouting, or fermenting foods to take advantage of the health-promoting properties of these nutritious ingredients.

Final thoughts

Lectins are a family of proteins that bind to carbohydrates and play an integral role in everything from immune function to glycoprotein synthesis.

Some research shows that they may have antimicrobial properties and help prevent cancer.

However, consuming large amounts can irritate the digestive tract and contribute to inflammation and nutrient malabsorption.

So what foods have them? They are present throughout the food supply, but grains, legumes, and nightshade vegetables such as tomatoes, potatoes, and eggplants are especially rich in lectins.

However, instead of completely separating lectin foods from your diet, focus on practicing proper preparation techniques to decrease lectin content and include a host of essential nutrients in your diet from foods containing healthy lectins.

You are cooking your food before eating. Removes lectins almost entirely from food. Soaking, sprouting, and fermenting your food can lower the lectin content. You can also try pressure cooking which is another option for cutting them down into potatoes and tomatoes.