The surprising truth about lectins | Dr. Will Bulsiewicz

What are lectins, and are they dangerous? These “antinutrients” have come under attack and were recently the subject of a dietary fad fueled by a popular book. As always, there’s more to the story.

In today’s episode, Jonathan is joined by Dr. Will Bulsiewicz to dive deep into the world of lectins. They dissect questionable studies, debunk myths, and offer expert advice about how to approach foods containing these misunderstood compounds.

Will is a board-certified gastroenterologist with 14 years of experience. He’s also the New York Times best-selling author of Fiber Fueled and ZOE’s U.S. medical director.

Mentioned in today’s episode:

Lectins as bioactive plant proteins: a potential in cancer treatment from Critical reviews in food science and nutrition

Plant-Derived Lectins as Potential Cancer Therapeutics and Diagnostic Tools from BioMed research international

A legume-based hypocaloric diet reduces proinflammatory status and improves metabolic features in overweight/obese subjects from European journal of nutrition

Dietary legume consumption reduces risk of colorectal cancer: evidence from a meta-analysis of cohort studies from Scientific reports

Intake of legumes and cardiovascular disease: A systematic review and dose-response meta-analysis from Nutrition, metabolism, and cardiovascular diseases : NMCD

Legume consumption is inversely associated with type 2 diabetes incidence in adults: A prospective assessment from the PREDIMED study from Clinical nutrition (Edinburgh, Scotland)

The Effects of Legume Consumption on Markers of Glycaemic Control in Individuals with and without Diabetes Mellitus: A Systematic Literature Review of Randomised Controlled Trials from Nutrients

Effects of dietary pulse consumption on body weight: a systematic review and meta-analysis of randomized controlled trials from The American Journal of Clinical Nutrition

The "white kidney bean incident" in Japan from Methods in Molecular Biology

Fructan, Rather Than Gluten, Induces Symptoms in Patients With Self-Reported Non-Celiac Gluten Sensitivity from Gastroenterology

Books:

[skyyy]

I’m Indian and we’ve been eating red kidney beans forever. They literally cannot be consumed raw or semi cooked unless you are wanting to torment yourself. We always soak them overnight and pressure cook them until they are properly soft and properly delicious with all the spices we add to our beloved ‘rajma’. And we eat them with white rice. It’s about balance and well tested food combinations.

[lynnecameron]

I was told by my grandmother that dried beans need to be soaked in boiling water overnight then boiled for around an hour and a half to ensure they are safe.

[simonearantes]

I was diagnosed with Hashimoto’s thyroiditis in Dec21 with ANTI TPO over 1300 and FAN over 140. So I did included some vit D, B6, B9, Mg and mainly took all lectins rich food from my diet and I was vegetarian! By Dec 22 FAN was negative and Anti TPO below 100. I was still vegetarian and many others did benefit from a almost lectin free diet (taking out the lectin rich foods - not all legumes are lectin rich, there are plenty of legumes to be eaten on a “lectin free” diet. I get more studies should be carried out and again there are plenty of legumes to eaten that are lectin free or very low in lectins. That is my experience and I am so grateful for all the research and discussions that Zoe does.

[leninlau]

I’m from Central America and we eat beans there every day at least twice a day, and never got sick, and I’m still eating black beans, red beans, all kinds of beans, never gotten sick❤

[FawziaTung]

Dr Steven Gundry (obviously the person you did not name) did recommend soaking and pressure cooking for legumes. As a retired medical doctor, I would be reallly interested in looking at the “favorite” study you mentioned. It was probably carried out with “healthy” subjects. I, on the other hand, was so ill that I got my will drawn before I stumbled upon The Plant Paradox. Sorry to rock your boat, but, after going on a low-lectin diet, I’m now healthy and traveling all over the world. I grow my own organic vegetables, and buy organic meat, chicken and eggs from a nearby farmer.
After I saw the video on soaking and pressure cooking legumes, I happily made a pot of lentil soup. Well, I became so ill that I’m not touching legumes anymore with a six-foot pole. By the way, legumes and whole grains are not the only culprits. Fruits produced thousands of miles away and shipped to you to be eaten out of season is another large source of “bad” lectins. Not surprisingly, I have now grown a food forest in my backyard, front yard, and side yard. But I’ll stop here. Obviously, you will label me as an anecdote and not part of a controlled study and brush me off. That’s okay. Just saying that every human is an individual entity, and do not all react the same way to all substances.

[aravindk]

I was told quinoa is superfood and started consuming since 2015. I started seeing eczema on legs since 2016 and in early 2021 i had urticaria on neck. I had sleepless nights. But lately realized quinoa is the issue. I cut the quinoa for last 2 weeks and see lot of difference. It took 7 years to realize the issue. I spent 1000s of dollars in finding allergy tests and skin tests.

[mak]

I am African and beans are a staple in our diet. Beans ( all different types) are consumed 2/3 times per week and has been a staple for centuries. We soak beans overnight and are fully cooked until soft before consuming. It’s crazy how foods we have lived off and enjoyed for decades here in Africa are vilified in the west.

[AntidoteX]

Once I was short of potassium and, as a result, prone to infections and allergies. Every time I ate shop-bought canned beans, my arms itched. However, my own well-soaked and pressure cooked beans didn’t cause any symptoms.

[san.magic]

Growing up in Eastern Europe we ate cocked beans almost every day. In other words, we survived eating beans, potatoes, fruits and very small portions of meat. I can’t understand anyone believing that beans are dangerous food:))

[ionutmiron]

I would like to present you my case:
4 years ago, I practiced bodybuilding and had a diet rich in lectins: red beans, oatmeal, soy, wholemeal bread (I admit, not very well cooked)
After about 2 years of the diet, the problems started, the joint pains in the legs started, two toes swelled, and the doctors' conclusion was reactive arthritis.
After a year and some treatments, I managed to calm the disease (with a gluten-free, no ultra-processed, nseed oil-free, dairy-free diet).
Now, if I exaggerate even with gluten-free bread, adverse reactions begin to appear.

[RhaniYago]

Some weeks ago I watched a video by an MD who really condemmed beans and other foods because they contain lectins. First I was shocked because as someone not eating meat I need my proteins coming from somewhere and I really love my beans. And who on earth would eat kidney beans raw? I later found some information about this MD showing that he was not really very reputable. I am glad I got more indepth information from Zoe. Thanks a lot for this.

[Anita-whvr]

I went to three gastroenterologists (in Switzerland) because of severe gastrointestinal issues, and I thought it was gluten. Non of them told me about fructans, only that there was nothing showing gluten sensitivity! I discovered by myself by doing an elimination diet and the FODMAP App by the Monash University. If gastroenterologist and doctors in general don’t take those things seriously including the patients, no wonder people listen to lonely wolfs. Patients often are by themselves!!!!

[MsCalliopeK]

I love love love Dr. Bulsiewicz's enthusiasm (and his nerdiness)! And how clearly and succinctly he explained the issue. Thank you so much

[biscuit]

These questions are much better than they used to be, interviewer getting out of the way more than before and fewer inane interjections, and less worried about viewers ability to comprehend what’s being said - well done 👍🏾 this is now a channel that’s a bit more tolerable which is good cause the info is superb!

[MM-wufl]

I went on a wfpbdiet for 1 year and I ate legumes every day. I had a lot of diarrea and bloating. I lost weight and started to have thyroid problems and joint pain. I discontinued the diet and started the Mediterranean diet. I don't eat legumes, glutine, pork. I eat fish 4x week, chicken 1x week and have goat/sheep cheese and kefir, eggs 5x week and I eat a lot of vegetables, rice, nuts, fruits and seeds and 2 tblsp evo. I am feeling much better and I don't look or feel sick anymore.

[anahirsch-toth]

I grew up eating veggies, 1 oz of meat a week!! Lots of beans. Post WWII Europe. Yes, beans were were soaked overnight, boiled with some baking soda for 1 hour or so in the morning, and then another 2-3 at the low temp. My brother had 3rd bowl of bean soup and bread...and is still 6"2, all teeth but one at the age of 84. Zero CV issues, no degenerative disorders. Writes books, teaches postdoctoral students, and works in his orchard and vineyard.

[douglasjrhodes]

Really appreciate bringing clarity back to the goodness of beans, other legumes and eliminating my paranoid approach to lectins after reading this cardiologist’s anti-lectin book, watching his videos, etc. I did catch him personally, as I live in Italy of one aspect of eating only tomatoes without the skin and seeds. Crazy stuff! We eat pomodorini or cherry tomatoes in our pasta several times a week, usually with all of the skin and seeds.

[drpathydiotto]

Thank you so much Dr B. It is always a pleasure to hear you. You are such an inspiration! 🥰

[reimaravalk]

Dear gentlemen. Thank you very much for addressing the topic of fodmaps and fractals as opposed to lectins in this podcast. It really provides clarification to people about their food sensitivities, including myself. Many people do not realise that it is actually the fructans that they are sensitive to and not gluten or lectins. I learned this about myself and now I adjust my diet accordingly. Looking forward to the next episode addressing ibs and fodmap. Kind regards Reimara

[jacquelineanderson]

Thank you so much for getting the good science based diet advice out there and making it accessible to non scientists. It’s so badly needed.