Do dietary lectins in Wheat cause disease? | BMJ

Lectins stimulate class II HLA antigens on cells that do not normally display them, such as pancreatic islet and thyroid cells.9 The islet cell determinant to which cytotoxic autoantibodies bind in insulin dependent diabetes mellitus is the disaccharide N-acetyl lactosamine,10 which must bind tomato lectin if present and probably also the lectins of wheat, potato, and peanuts. This would result in islet cells expressing both class II HLA antigens and foreign antigen together—a sitting duck for autoimmune attack. Certain foods (wheat, soya) are indeed diabetogenic in genetically susceptible mice.11 Insulin dependent diabetes therefore is another potential lectin disease and could possibly be prevented by prophylactic oligosaccharides.

Another suspect lectin disease is rheumatoid arthritis. The normal human IgG molecule possesses carbohydrate side chains, which terminate with galactose. In rheumatoid arthritis much of the galactose is missing, so that the subterminal sugar—N-acetyl glucosamine—is exposed instead. These deficient IgG molecules feature strongly in the circulating immune complexes that cause fever and symptoms.12 In diet responsive rheumatoid arthritis one of the commonest trigger foods is wheat, and wheat lectin is specific for N-acetyl glucosamine—the sugar that is normally hidden but exposed in rheumatoid arthritis. This suggests that N-acetyl glucosamine oligomers such as chitotetraose (derived from the chitin that forms crustacean shells) might be an effective treatment for diet associated rheumatoid arthritis. Interestingly, the health food trade has already siezed on N-acetyl glucosamine as an antiarthritic supplement.

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.14 Lectins also cause discharge of histamine from gastric mast cells,15 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. 

More reasons to avoid wheat & gluten

gluten is composed of gliadin and glutenin. It has long been believed that only the gliadin portion is responsible for gluten sensitivity. According to a study published in the European Journal of Gastroenterology and Hepatology (2006), “it is highly probable that the glutenin proteins are toxic.” In other words, laboratories are only testing for half of the potentially immune-reactive components of gluten. And for the half that they do test (gliadin), only one-quarter of it is being measured (alpha gliadin).

Gluteomorphins: Are You an Addict?

Many people who go gluten-free claim that the diet actually makes them feel worse. This can be quite baffling if one is unfamiliar with gluteomorphins. Common in autistic children, gluteomorphins are opiod peptides formed during the digestion of the gliadin component of the gluten protein (3). For these folks, getting off of gluten can be like kicking a cocaine habit!

The discontinuance of any addictive substance will result in a period of withdrawal lasting a few days to several weeks. In the case of gluteomorphin withdrawal, symptoms can include neurochemical imbalances, altered mood, and gastrointestinal distress. Yes, gluten can be a drug.

An individual whose immune system is making antibodies to gluteomorphins will have a much tougher time in the early phases of a gluten-free diet.

Traditional gluten testing does not look for gluteomorphin antibodies.

Can Eating Wheat Cause Psychiatric Problems?

Wheat contains high amounts of wheat germ agglutinin (WGA); a glycoprotein classified as a lectin, which is largely responsible for many of wheat’s ill effects. Other grains high in lectins include rice, spelt, and rye.

“WGA can pass through the blood brain barrier (BBB) through a process called ‘adsorptive endocytosis’ … WGA may attach to the protective coating on the nerves known as the myelin sheathand is capable of inhibiting nerve growth factor which is important for the growth, maintenance, and survival of certain target neurons. WGA binds to N-Acetylglucosamine which is believed to function as an atypical neurotransmitter functioning in nocioceptive (pain) pathways.”

The traditional ways of addressing many of these anti-nutrients is by sprouting, fermenting and cooking. However, lectins are designed to withstand degradation through a wide range of pH and temperatures. WGA lectin is particularly tough because it’s actually formed by the same disulfide bonds that give strength and resilience to vulcanized rubber and human hair.

Furthermore, because lectins are so small, and hard to digest, they tend to bioaccumulate in your body, where they can interfere with biological processes. WGA is particularly troublesome in this regard. Studies indicate it has a number of health-harming characteristics and activities:

Pro-inflammatory—WGA stimulates the synthesis of pro-inflammatory chemical messengers (cytokines) in intestinal and immune cells, and has been shown to play a causative role in chronic thin gut inflammation.

Immunotoxicity—WGA induces thymus atrophy in rats , and anti-WGA antibodies in human blood have been shown to cross-react with other proteins, indicating that they may contribute to autoimmunity . In fact, WGA appears to play a role in celiac disease (CD) that is entirely distinct from that of gluten, due to significantly higher levels of IgG and IgA antibodies against WGA found in patients with CD, when compared with patients with other intestinal disorders.

Neurotoxicity— WGA can cross your blood brain barrier through a process called “adsorptive endocytosis,” pulling other substances with it. WGA may attach to your myelin sheath and is capable of inhibiting nerve growth factor, which is important for the growth, maintenance, and survival of certain target neurons.

Excitotoxicity— Wheat, dairy, and soy contain exceptionally high levels of glutamic and aspartic acid, which makes them all potentially excitotoxic. Excitotoxicity is a pathological process where glutamic and aspartic acid cause an over-activation of your nerve cell receptors, which can lead to calcium-induced nerve and brain injury. These two amino acids may contribute to neurodegenerative conditions such as multiple sclerosis, Alzhemier’s, Huntington’s disease, and other nervous system disorders such as epilepsy, ADD/ADHD and migraines.

Cytotoxicity—WGA has been demonstrated to be cytotoxic to both normal and cancerous cell lines, capable of inducing either cell cycle arrest or programmed cell death (apoptosis).

Disrupts Endocrine Function—WGA may contribute to weight gain, insulin resistance, and leptin resistance by blocking the leptin receptor in your hypothalamus. It also binds to both benign and malignant thyroid nodules , and interferes with the production of secretin from your pancreas, which can lead to digestive problems and pancreatic hypertrophy.

Cardiotoxicity—WGA has a potent, disruptive effect on platelet endothelial cell adhesion molecule-1, which plays a key role in tissue regeneration and safely removing neutrophils from your blood vessels.

Adversely effects gastrointestinal function by causing increased shedding of the intestinal brush border membrane, reducing the surface area, and accelerating cell loss and shortening of villi. It also causes cytoskeleton degradation in intestinal cells, contributing to cell death and increased turnover, and decreases levels of heat shock proteins in gut epithelial cells, leaving them more vulnerable to damage.

Aside from high amounts of WGA, wheat also contains a number of other potentially health-harming components, including:

  • Gliadin (an alcohol soluble protein component)
  • Gliadomorpin (exorphins, or group of opioid peptides that form during digestion of the gluten protein)
  • Enzyme inhibitors

One recent study, published in the Scandinavian Journal of Gastroenterology last year, found that even those who do not present symptoms of celiac disease may have antigliadin antibodies, which was found to increase the risk of depression in elderly individuals.

“Individuals with recent-onset psychosis and with multi-episode schizophrenia who have increased antibodies to gliadin may share some immunologic features of celiac disease, but their immune response to gliadin differs from that of celiac disease.”

 

A bit more on Gliadorphin
Gliadorphin (also known as gluteomorphin) is an opioid peptide that is formed during digestion of the gliadin component of the gluten protein. It is usually broken down into amino acids by digestion enzymes. It has been hypothesized that children with autism have abnormal leakage from the gut of this compound, which then passes into the brain and disrupts brain function. This is partly the basis for the gluten-free, casein-free diet. Studies of this diet have had important methodological flaws, and the scientific evidence is not adequate to make treatment recommendations.

Wheat and gluten can hurt you even if you don’t realize it and don’t test positive for celiac….

It’s interesting that Celiac can strike at any time, and that even if you don’t test positive, you could still have an allergy….and that your symptoms could be mild or severe…and that you may never know the damage gluten is - or is not causing you.

Celiac disease, an autoimmune disorder that can appear at any age and is caused by an intolerance to gluten.

Cooper tested negative for celiac disease, but the doctor advised her to try a gluten-free diet anyway.

“Within a week of eliminating [gluten], I started to feel markedly better,” says Cooper, now 36, from Melbourne, Australia. “It wasn’t a gradual feeling better; it was almost a crossing-the-street kind of thing.”

In fact, experts now believe that celiac disease represents just one extreme of a broad spectrum of gluten intolerance that includes millions of people like Cooper with less severe — but nevertheless problematic — reactions to the protein.

While celiac disease affects about 1 percent of the U.S. population, experts estimate that as many as 10 percent have a related and poorly understood condition known as non-celiac gluten intolerance (NCGI), or gluten sensitivity.

“Gluten is fairly indigestable in all people,” Leffler says. “There’s probably some kind of gluten intolerance in all of us.”

Experts now think of gluten intolerance as a spectrum of conditions, with celiac disease on one end and, on the other, what’s been called a “no man’s land” of gluten-related gastrointestinal problems that may or may not overlap.

Celiac patients can also develop headaches, tingling, fatigue, muscle pain, skin rashes, joint pain, and other symptoms, because the autoimmune attack at the root of the disease gradually erodes the wall of the intestine, leading to poor absorption of iron, folate, and other nutrients that affect everything from energy to brain function.

People with gluten sensitivity sometimes experience these far-reaching symptoms as well, though it’s less clear why.

More Ways Gluten and Wheat Can Hurt You - Beyond Celiac

Celiac disease is hardly the beginning and end of this story. Dermatitis herpetiformis is a rash that results when gluten induces an autoimmune response in the skin rather than the gut, and there is evidence that gluten can provoke a similar autoimmune response in the brain as well.

Gluten sensitivity or intolerance …. might be mediated by the innate, rather than the adaptive, immune system, meaning that T and B cells are not involved.

Gluten “intolerance” is simply when people report that the feel a lot better when they stop eating gluten. It reportedly affects about 10% of the population, but that’s only the 10% we currently estimate, and the effects could be more far reaching than we currently understand - the skin problems and brain issues are likely only the beginning. We’re not used to eating wheat or gluten and my guess is that future research likely uncovers more issues.