I've read descriptions by Wolf and Cordain of what lectins do in the gut, but the devil's advocate in me is just wondering whether this is "fact" or just a highly controversial theory (given that many people disagree with the no-grains thing.) Has the impact of lectins on the gut actually been scientifically proven? And if not, why not?
asked byRenee_2 (11698)
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on October 22, 2011
at 11:03 AM
A little overview:
Essential sugars are sugars that have specific biological functions within the body. Different types of sugars coat the surfaces of cells and help them to communicate with each other (...) Plant lectins are poisonous proteins. Ricin is a lectin made from castor beans, and a well-known poison that has been used by the KGB and terrorists in the USA that causes massive blood clotting. Lectins have a wide variety of different structures and are grouped together under the term "lectin" based on their effects on human blood. Lectins are carbohydrate-binding proteins that attach themselves to essential sugars in the human body. They are glycoproteins just like their protective counterparts. Essential sugars typically coat the surfaces of cells and help them to communicate. **Lectins bind to the essential sugars and disrupt cellular communication. When they do this, they can cause agglutination ??? that is, the blood may clump together. It is thought that plant lectins exist as defence mechanisms. Many have lethal effects on various insects and cause stomach upsets in foraging animals ??? and humans.
Here's an interesting paper:
Among the effects observed in the small intestine of lectin fed rodents is stripping away of the mucous coat to expose naked mucosa and overgrowth of the mucosa by abnormal bacteria and protozoa.Lectins also cause discharge of histamine from gastric mast cells, which stimulates acid secretion. So the three main pathogenic factors for peptic ulcer???acid stimulation, failure of the mucous defence layer, and abnormal bacterial proliferation (Helicobacter pylori) are all theoretically linked to lectins.
The mucus stripping effect of lectins also offers an explanation for the anecdotal finding of many allergists that a ???stone age diet,??? which eliminates most starchy foods and therefore most lectins, protects against common upper respiratory viral infections: without lectins in the throat the nasopharyngeal mucus lining would be more effective as a barrier to viruses.
on October 21, 2011
at 03:03 AM
Most doctors cannot make money unless they drug you or cut you (surgery). Think: lifetime customer value - a person that's sick the rest of their life - autoimmune, diabetes, arthritis - most modern diseases - that's an industry for so many people. Don't expect them to cure you or put you in remission unless they are Paleo-friendly! When they do give give nutritional advice (it's usually conventional wisdom or worse)!
on February 26, 2013
at 02:17 AM
I too want to know more about the SCIENCE behind these claims. I am very intrigued by the lectin debate and I know we ALL want the truth. I just find it hard to believe that more reserchers have not tried apply normal trails to this....very frustrating.
on October 23, 2011
at 01:23 PM
I'm so glad you posed this question -- I was wondering the SAME THING. This is an underestimated factor I believe in epidemic levels of food allergies (GMO peanut/soy/corn), ADHD, ASD, autoimmune disorders and cancer...because all are associated if not caused by intestinal permeability. I used to think it was gluten dominant phenomenon but lectins do it too if not worse (esp if genetically engineered for high expression of lectins and multiple gene copies, to attempt to prevent resistance patterns in native pests/beetles).
What do you think of sources of lectins (from GMO crops) impervious to cooking and that may even be propagated by horizontal gene transfer to our gut microbiome...?
(1) http://www.organicconsumers.org/articles/article_11361.cfm [Spilling the Beans: Unintended GMO Health Risks]
[Maternal and fetal exposure to Bt Lectin/toxin and pesticides associated to genetically modified foods in Eastern Townships of Quebec,Canada]
Abstract: Pesticides associated to genetically modified foods(PAGMF), are engineered totolerate herbicides such as glyphosate (GLYP) and gluphosinate(GLUF) o rinsecticides such as the bacterial toxin bacillus thuringiensis (Bt). The aim of this study was to evaluate thecorrelation between maternal and fetal exposure, and to determine exposure levels of GLYP and its metabolite aminomethylphosphoricacid(AMPA), GLUF and its metabolite 3-methylphosphinicopropionicacid(3-MPPA) and Cry1Ab protein(a Bt toxin) [MICROBIAL LECTIN] in East- ern Townships of Quebec, Canada. Blood of thirtyp regnantwomen(PW) and thirty-nine nonpregnant women (NPW) were studied.Serum GLYPand GLUF were detected in NPW and not detected in PW. Serum 3-MPPA and CryAb1 toxin [Bt LECTIN] were detected in PW, their fetuses and NPW. This is the first study to reveal the presence of circulating PAGMF inwomen with and without pregnancy, paving the way fora new field in reproductive toxicology including nutrition and utero-placental toxicities.