Lectins — A Little Known Trouble Maker

In All Health Watch, Featured Article, Health Warning by Natural Health Dossier20 Comments

While most of the world seems to be touting the benefits of whole grains these days, a few people are insisting that grains are not as healthy as we think.

One of the reasons grains may be a problem in human nutrition is because they contain lectins, a class of molecules called glycoproteins (molecules that contain a protein and a sugar).

While dietary lectins are known in the scientific and nutritional communities, most lay people and even many medical professionals don’t know about them.

Lectins are involved in food allergies/sensitivities, inflammation and autoimmune disease, just to name a few.  For instance, lectins are linked to celiac disease. Even weight gain and low energy can be linked to lectins.

Whole grains, peanuts, kidney beans, and soybeans are high in lectins. Cow’s milk, nightshade vegetables (like potatoes and tomatoes) and some seafood also contain fairly high amounts of lectin.  In fact, estimates are that about 30% of our foods contain lectins, and about 5% of the lectins we eat will enter our circulation.

Lectins are problematic because they are sticky molecules that can bind to the linings of human tissue, especially intestinal cells.   In so doing, they disable cells in the GI tract, keeping them from repairing and rebuilding.1 Therefore, lectins can contribute to eroding your intestinal barrier (leaky gut).

Because the lectins also circulate throughout the bloodstream they can bind to any tissue in the body ­— thyroid, pancreas, collagen in joints, etc.2 This binding can disrupt the function of that tissue and cause white blood cells to attack the lectin-bound tissue, destroying it. This is an autoimmune response.  The lectins in wheat for example, are specifically known to be involved in rheumatoid arthritis.

But why do only some people react to the lectins in foods while others can eat them with no apparent problems?   There are two answers to this question.  First, many people may be having problems but they just don’t realize it.  For example, autoimmune thyroiditis could be caused by dietary lectins.6

As another example, many of our patients who thought they had no food intolerance at all have experienced much improved energy and weight control when they eliminated wheat and dairy.  They didn’t realize until after they eliminated these foods that they were being affected by them.

But certainly many people tolerate these foods — why?

The answer lies in the balance of gut flora and a person’s immune system.  When you have adequate beneficial flora, it serves as a protective barrier against substances that travel through the intestines, including lectins.  But importantly, beneficial flora are needed to keep the production going in the intestines of two lectin-protective substances, mucin and secretory IgA.3,4

Mucin, like lectin, is a glycoprotein in the mucous lining of the intestines.  When lectins travel through the intestines, they should have mucin to bind to, rather than intestinal cells.  But if mucin is missing, lectins will bind to intestinal cells instead.  Secretory IgA also binds to lectins, preventing them from causing damage.5

If you have any lectin-related health issues like arthritis, allergies or autoimmune disease, our experience shows it is very helpful to reduce your intake of lectins, especially from wheat.  It’s also very important to balance immunity by working on stress management and gut health.

By taking a good quality probiotic you’ll help stimulate adequate mucin and secretory  IgA production.3,4 And controlling your stress response will help prevent the over production of IgA and maintain immune balance in the gut to improve your tolerance to lectins.


  1. Pierini C. Vitamin Research News. Jan 2007. 21(1): 1-4.
  2. http://www.sciencedaily.com/releases/2007/08/070801091240.htm.
  3. Eur J Clin Nutr. 1993 Oct;47(10):691-9.
  4. Deplancke B and  Rex-Gaskins H. AJCN. June 2001. 73(6):1131S-1141S.
  5. Buts JP, et al. Digestive Disease and Sciences. Feb 1990. 35(2): 251-56.
  6. Cordain L et al. British Journal of Nutrition (2000), 83, 207–217.


  1. I have just read an article about lectins in banana’s possibly that can help in HIV prevention. May be Dr. La Valle can substantiate this.

  2. Hi, Nice article. I have been eating this way for over 10 plus years I am blood type A , due to the work of Dr. Peter D’Adamo who has written over 10 books on the role of lectins in health. I have increased health and vitality that many of my peers do not have. Thank you, Andrea

  3. Have blood groups been checked to see if they are tolerant or intolerant to the affect of Lectins ?

  4. Yes it is true that Lectins are found in almost all food and are impossible to avoid, but what we all need to know is that they are blood type (o,a,b,ab) specific. Lectins that are harmful for one blood type can actually be beneficial to another. Every cell in you body has a sugar molecule call antigens and depending on your blood type determines weather or not these food lectins attach themselves to the cell and agglutinate and cause inflammation, that can lead to disease and other health problem…..
    For more information, check out Dr. Peter D’Adomo’s book Eat Right For Your Type (the blood type diet) talks all about it.

    1. Except when a myriad of factors causes the fail-safe mechanism of the immune system to FAIL, causing a shopping list of diseases: heart disease, diabetes,MS, certain cnacers, obesity, etc. That list is too long to include here. Lectins are not the only enemy, but they are certainly a big one. The overall condition of the immune sytem of most north americans is so breathtakingly awful that eating grains, legumes and dairy that are loaded with lectins is an invitation to health disaster. Eat protein, green veggies, flavinoids, fruits (avoiding high sugar varieties). Ditch the processed food and sugar too. Drink water, tea, coffee, and two glasses of red wine a day. Good health will be yours, and you’ll look FANTASTIC regardless of your age!

  5. Thank you for this pertinent information. I have just recently been cofirmed as being celiac although I have been suffering ever since my teen years and just could not find the medical answers from my doctor, or the many dermatologists and allergerists he sent me to see. Even though I am now gluten and wheat free I have had a sudden skin breakout (hives) and have not been able to control it until now after reading your article on lectins I realize my limited tolerance for the nightshade family of tomatoes, potatoes, and eggplant as I have increased my intake since adopting more of a vegetarian diet.

  6. Thank you for your news sheet.

    Your comments – Why do only some people react to the Lectins in food, while others can eat them with no apparent problems?

    My theory is this – I am a Blood type A. The A’s have thick blood, do not sweat and have a sluggish circulation even after exercise, and feel the cold.
    I am aware that the Blood type O, have thin blood, sweat easily even if they havent been exercising, They frequently complain of feeling hot when the temperature is on the cool side.

    The Blood type O eat red meat. Type B and type AB eat lamb. The blood type A, the tribe that travelled out of Africa to South East Asia as my ancesters did, were unable to digest red meat.

    The poor A’s from Asia with their thick blood and poor circulation, I fear suffer the most.

    I hope that my comments might be of some use to you.

    1. I don’t know about the above reply, I am an O blood type and I can’t tolerate any legumes – I can’t even touch them, and have to be careful about eating only a little red meat (couldn’t eat it at all for a while)after a good cleanse and some gut repopulation I can eat some, and only soaked grains or I have digestive troubles.

  7. nice article but one problems is that lectin is not a glycoprotein but a protein that binds sugar.

  8. Why not LIST the seafoods with lectins? I will have to go searching.

  9. Anymore you can’t hardly eat anything!! I guess the old mantra rings true, anything and everything but in moderation and stop being American gluttons feasting at the trough.

  10. have you ever checked into lectins and your blood type, interesting connection, eat right for your blood type

  11. The author states:

    “In fact, estimates are that about 30% of our foods contain lectins, and about 5% of the lectins we eat will enter our circulation.”

    Lectins occur in 100% of all living organisms: plants, animals, fungi, bacteria and viruses. Even humans produce a number of lectins.

    Who came up with the percentage of foods that have lectins? All of them – that is, 100% – are loaded with lectin units. The difference is that some cause anti-nutritional, degenerative reactivity, some are completely benign, or neutral, and some are actually regenerative, or beneficial.

    You’re not sensitive to red meat. You are sensitive to the wheat (or any grain) in the buns (or any baked goods), to the sugar and the vinegar in the condiments.

    @No one has “slow” blood. Only nutrition and hydration (or dehydration) your clotting factors. If you’re a caffeine addict (same as a meth addict, chemically), and if you consume voluminous quantities of sugars (most people do, although they don’t realize it), then you are consistently dehydrated, and when your caffeine (i.e., stimulant supply) is low, then your heart, which is already weakened from the caffeine, will beat much more slowly. Since you are dehydrated (already mentioned), your blood will actually be more viscous and less efficient. But that’s nothing mysterious. You caused your own condition. You could improve it if you like.

  12. This is a great article!

    and @ Eberhardt Kalmar Huhn

    great reply!

  13. Galectins :
    S-type lectins are called galectins. There are 3 subfamilies of galectins based on their structure. One of the most important functions of galectins is the regulation of inflammation. Excessive galectin -3 in the body has been shown to contribute to over expressed inflammatory response and is associated with disease progression in such diseases as arthritis , chrohns disease, cancer and heart disease.
    There is a blood test which can measure galectin -3 levels but you would probably need to ask to have it done.
    There are 3 natural galectin -3 inhibitors which I am aware of: 1. Modified citrus pectin 2. A type of ginseng called Noto Ginseng 3. an extract from an endangered tropical tree which I believe grows in India and parts of S.E. Asia. I forgot the name.
    Numbers 1 and 2 are widely available but number 3 would be much harder to get and I only know of one chemical company in the U.S. which carries it for larger commercial uses only .
    Larch may also be a galectin -3 inhibitor but I’m not sure of this.

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