HEALTH & WELLNESS
What are Lectins? Is a Lectin-Free Diet Good or Bad?
BY SMARTERCHOICES - OCTOBER 8, 2021 - 5 MINS READ
Some things are inevitable. Every year it seems like there is a new “must-have” and “must-avoid” food. Recently, there has been a lot of talk about avoiding lectins. But, what even are lectins? Is there any truth to the recent fad of avoiding them, or is it all just hype?
Could vegetables and healthy grain actually be bad for you?
A 2017 book by Dr. Steven Gundry, titled The Plant Paradox (Harper Wave) has been credited with popularizing the “lectin-free” diet. With support from celebrities, like American Idol winner, Kelly Clarkson, the lectin-free diet benefited from free advertising and some mainstream attention.
In the now controversial book, Grundy claims lectins (a broad group of plant proteins) are the cause of most modern illnesses. He blames this plant protein on obesity, gastrointestinal issues, autoimmune disorders, and even allergies.

To anyone with even a little bit of health/nutritional education, this sounds fishy. This diet goes directly against everything you learned in high school health class, and the dietary recommendations of the American Cancer Society, American Heart Association, American Diabetes Association, and every other health organization out there.

Gundry claims his findings are based on research and data from his own patients as evidence. Gundry even conducted his own “study”, but this was not peer-reviewed, and even lacked a control group. Meaning his findings are more observation than fact. If you look for other legitimate studies on lectins, you will see there is little information out there. Most studies are inconsistent and are not conducted on human subjects. So, you have to take everything Gundry says with a healthy serving of salt.


In this article, we will explore the topic of the lectin-free diet, in hopes of uncovering the truth.

What are Lectins?

Lectins can be found in a variety of foods.

Lectins are a type of plant protein that can be found in nearly all foods. It is believed that foods with the highest level of lectins are whole grains, legumes, and nightshade vegetables.


There are many different types of lectins, and these have many different effects on the body. Some lectins can make plant foods difficult to digest. The most infamous and extreme of this is phytohaemagglutinin (the lectin that causes raw kidney beans to be toxic to humans). Remember, by simply cooking kidney beans and other foods containing lectins, you are basically removing them and any negative effects associated with lectins.


If you are asking yourself, “why would I risk eating lectins?” Keep in mind that lectin-containing foods contain many of the essential nutrients that are critical to your health.

The Downsides of a Lectin-Free Diet

Tomatoes contain the lectin – lycopene.

There are several pieces of evidence that we need some lectins in our diet.
Lectin bind to sugar and this sugar-binding activity means lectins could be needed for normal digestion. So keep in mind that adhering to a lectin-elimination diet could negatively affect your ability to absorb nutrients, and could result in nutrient deficiencies.

Another concern with a lectin-free diet is whether or not it can provide you with all the essential nutrients you need. Lectins are found in fruits and vegetables – and many of these have disease-preventing characteristics. Like tomatoes, for example, have a lectin called lycopene, which has been shown to have positive effects on the cardiovascular system.

Also, keep in mind, there are many studies and documentation of the importance of plants and plant-heavy diets for living a long and healthy life. If lectins were so bad for us, these findings would not exist. Plant-based diets are also crucial for getting anti-toxins and a variety of nutrients and fibers that are important for the gut microbiome.
Health Benefits of Eating Lectins

Tomatoes contain the lectin – lycopene.

As we mentioned, cutting foods that contain lectins from your diet would mean you’re also cutting out important nutrients. Take squash and pumpkin, for an example. Gords and other vegetables in this family contain a range of phytonutrients that possess serious antioxidant activity. They also appear to be beneficial for healthy intestines, and a healthy gut ecosystem.

Legumes, are also a no-no if you are following a lectin-free diet. Legumes contain a wide variety of healthy phytochemicals, and if we look at nations that consume legumes at a high rate, they have low rates of colon cancer. There are also studies that support the gut-protective properties of legumes!


Another study showed that when adding fully cooked black and navy beans to an omnivorous diet, there are positive effects on the gut microbiome, and can even increase the production of important short-chain fatty acids, and even help to protect against intestinal permeability.


In conclusion: Lectin-containing foods have clear research supporting their positive health benefits, while the research on a lectin-free diet is not even close. So, we should include them in our diet.


The lectin-free diet may have worked out for Kelly Clarkson, but for the average American who has to balance family, work, and more – the data and research are not there to warrant an extreme elimination diet like this. But, are you aware of these bad habits that are ruining your eating plan? Or read up on how gut health is important for the aging process.