If you’re here, you’re probably wondering – should you avoid lectins? This is a complicated question. Perhaps you have heard about the benefits of avoiding lectins, or maybe you are just wondering what the heck a lectin is. Either way, you are in the right place!
Recently I saw a post on Instagram post discussing how current dietary recommendations recommend low fat diets for heart disease and how this is bad advice.
Feeling a moral duty to say something, I commented on the post, saying how the Academy of Nutrition and Dietetics actually recommends replacing saturated fats with unsaturated fats, which is not a low fat diet. (source) I then briefly mentioned that the Mediterranean diet is the most researched diet for heart health.
Innocent enough right? Anyways, I got a lovely response from a lady claiming that the Mediterranean diet is actually not the best diet. She recommended that I should educate myself by reading the “Plant Paradox”. This later led to some nice back and forth where I explained the current research on nutrition and heart health. I mentioned that maybe doctors (a doctor wrote the book, by the way) are not qualified to give nutrition advice. Surprisingly, I did not convince her.
Despite it not being the most pleasant interaction, the conversation did inspire me to read more on this topic. The Plant Paradox’s main premise is that eliminating lectins from your diet will lower inflammation and treat autoimmune disease, diabetes, heart disease, etc.
And here is the killer. Lectins are basically in everything! Dr. Gundry (the author) recommends peeling your vegetables, eating your fruit ripe, avoiding grains with the exception of rice. He even recommends replacing brown rice with white rice. (source)
I didn’t like the diet for a few reasons. First off, you are eliminating so many nutrient dense foods. Secondly, any restrictive diet like this one is not sustainable. It is likely to cause relapse for those with histories of disordered eating, creates fear around food, and removes a lot of enjoyment out of life, especially in social situations.
Despite this, I still wanted to be open-minded and look into the research because, of course, if this was something that could cause a plethora of health problems, I wanted to know!
The evolution of the low lectin diet
I had first heard about lectins from the one and only Tom Brady. My brother purchased his TB12 book which outlined his workout and diet. He said he avoids certain foods, including peppers, eggplant, and tomatoes, because they lead to inflammation.
This was so foreign to me. I mean, these were health foods! So, I did a little bit of digging, and found out the reason he thought this way was because they contained lectins. I tried doing a little research into them, but, quite honestly, didn’t find much at all.
Since then, the anti-lectin craze has become more and more popular. Because of this, I was able to find more research and articles on the nutrient. But, unfortunately, the current research on lectins has been misinterpreted by those who are not experts in the nutrition field.
Due to this, it has become a common belief that lectins inhibit the absorption of certain minerals and worsen certain diseases, including autoimmune conditions and heart disease.
There have been a few reputable sources that have come out and said “please, don’t avoid foods high in lectins!”, but in case you haven’t read those articles, I’ve outlined why high lectin foods aren’t so evil in this article.
What are lectins? The Pros and The Cons
I think the best place to start off is just discussing what a lectin is and where it can be found.
Lectins are carbohydrate binding proteins that recognize and bind simple or complex carbohydrates. They are found pretty much everywhere – fungi, animals, bacteria, viruses and plants. They are found in the highest quantities in legumes, seeds, and grains.
Plant lectins specifically play a huge role in protecting the plant from insects and can help treat diseases caused by bacteria, viruses, and fungi. They also have been shown to reduce tumor growth in humans. (source)
One huge downside of lectins is that some forms are toxic – such as haemagglutinin, found in the red kidney bean. When not cooked properly, they can cause symptoms such as nausea, vomiting and diarrhea.
But good news! Haemagglutinin can be inactivated by cooking well soaked beans. In fact, all lectins can be largely eliminated through cooking. (source)
What lectins are more known for is their “anti-nutrient” properties. This means that high consumption of lectins will reduce absorption of some minerals, including calcium and iron.
But, as mentioned before, cooking typically is enough to reduce these lectins to a point where their harmful effects and miniscule. Methods such as soaking, sprouting, and fermenting are also shown to reduce lectin content. In addition, plant foods that contain lectins typically have high concentrations of other beneficial nutrients that protect against a variety of chronic diseases. (source)
But why are people having great results on a low-lectin diet?
It’s the same reason that people experience great results on low carb, keto, paleo, vegan, high carb (you name it). Well, I shouldn’t say one reason since there are a few.
Weight loss
Number one: weight loss. The people who you are hearing the success stories from, more often than not, have experienced weight loss (though the weight loss and benefits are often short-lived).
It goes a little something like this: “I have been eating a low lectin diet for a year now and I haven’t had any rheumatoid arthritis flare-ups! Plus, I’ve lost 25 lbs which is awesome!”. Hearing this, most people would think, wow, this low lectin diet really is legit! Plus, she lost some weight and I’d like to lose some weight so this may be the diet for me.
If you don’t have a strong research background, then this makes sense. In fact I have fallen for this many times in the past. But, more often than not, weight loss and exercise lead to improved outcomes. So was it the weight loss or the low lectin diet that caused the improvement?
The reason why there are so many controls in a good study is to prove that one variable leads to improved outcomes. The study should only change one variable to ensure this is the variable leading to positive outcomes.
For example, let’s say two studies are both examining the effect of a vegetarian diet on blood cholesterol (these 100% made up, by the way). One study tells all the participants to follow a vegetarian diet and to exercise 5 days a week for 30 minutes. All the participants experience weight loss and lower LDL levels (aka bad cholesterol).
The other study tells the participants to follow a vegetarian diet, but they are also advised to weigh themselves daily to ensure they do not lose or gain more than 2 lbs over the next 3 months. They are also told not to change their exercise habits. They experience a reduction of LDL levels.
Now, granted there needs to be more controls to make this a good study. But, the point I am trying to emphasize is that the first study not only changed the participants to a vegetarian diet, they also changed their weight and exercise.
So, what caused the lowering in LDL cholesterol? A vegetarian diet? Weight loss? Exercise? There is no way of knowing because they were not controlled. For the second diet, we know that the vegetarian diet was the likely cause of lowered LDL cholesterol because there was no weight loss or change in exercise for the patient.
This being said, there are plenty of other factors that may cause reduction of LDL, but we can at least agree that the second study is much more convincing.
So, to prove that a low lectin diet can reduce rheumatoid arthritis flare-ups, several studies need to be conducted comparing a normal diet with a low lectin diet. Participants need to be asked not to lose weight, change their exercise habits, start any new medications/supplements, initiate anything stressful in their life, etc. This may seem over the top, but this is how you build solid evidence, not through case studies!
Placebo effect
Number two: placebo effect. If you aren’t familiar with the term, a placebo is basically a fake treatment. For example, the first group will get the new pill for blood pressure and the next group will get a pill made of purely sugar – the placebo.
The mind is our greatest healer and our greatest enemy! If you believe in all your heart that a certain diet or pill or supplement will cure you, there is a good chance you start feeling a lot better.
You can even see this in clinical studies. One group is given a placebo and one group is given the treatment. Though the treatment group typically experiences stronger effects, the placebo group also tends to experience a change, just typically in a lesser amount.
But this doesn’t discount their experience. Their experience is just as real as the treatment group – but the cause wasn’t the treatment – it was their mind!
So, in this case, if someone is raving about the low lectin diet, even if their weight and exercise is stable, we also need to consider the placebo effect.
So, should you avoid lectins?
I won’t say I’m 100% convinced the low lectin diet does nothing for health. I’m just saying that there isn’t nearly enough evidence to support it.
Considering that highly restrictive diets rarely lead to anything but nutrient deficiency, stress, social isolation, and relapse, I just can’t ethically recommend the low lectin diet.
But, that being said, if, in the future, more high quality studies come out showing the low lectin diet is an effective treatment for a variety of chronic diseases, I wouldn’t mind revisiting it. But for now, no, I would not recommend a low lectin diet, for anyone