Saturday, August 1, 2015

Gluten-Free Diet: Myths and Facts

In the past half century (i.e., from 1950 to 2000), we have seen less infectious diseases because of antibiotics. However, in the same period, we have also seen higher incidences of immune-mediated diseases, including Type 1 diabetes, allergies and asthma. Why?

One of the immune disorders is celiac disease. Celiac disease (CD) is an allergy to gluten in grains. Active celiac disease can cause severe health problems, from stunting growth and osteoporosis to miscarriage. It strikes a relatively small number of people — just around 1 percent of the population. However, the statistics could be under-estimated. In [18], scientists have found:
Undiagnosed CD was found in 68 (0.9%) persons with similar age at sampling and 46 (0.8%) persons with similar years of birth.
Scientists has also shown that undiagnosed CD was associated with a nearly 4-fold increased risk of death compared with that in subjects without serologic evidence of CD.

In this article, we will discuss what could be the main causes of immune disorder such as celiac disease.

Could It Be the Food We Eat?


Foods we eat sometimes can make us sick. The stress response in our body created by "foreign" molecules in food is called xenohormesis[4]. They produce a stress response triggering the whole cascade of stress-related cellular signals that makes us sick. In [3], Dr. Rawlings have listed wheat and gluten products as one of such substances.

How come we have seen more immune-mediated diseases such as celiac disease in the past half century. Could it be the food we eat—wheat and gluten products? Here are some results that scientists have found:[5]
  • Could we haven't eaten wheat long enough to adapt to it as a species?
    • Wheat was first domesticated in southeastern Anatolia perhaps 11,000 years ago.
    • An archaeological site in Israel, called Ohalo II, indicates that people have eaten wild grains, like barley and wheat, for much longer — about 23,000 years.
    • Adaptation to a new food stuff such as milk can occur quickly — in a few millenniums in this case. So if it happened with milk, why not with wheat?
  • Could modern wheat varietals contain more gluten than past cultivars, making them more toxic?
    • According to recent analysis by Donald D. Kasarda, a scientist with the United States Department of Agriculture. He analyzed records of protein content in wheat harvests going back nearly a century. It hasn’t changed.
  • Do we eat more wheat these days?
    • Wheat consumption has, in fact, increased since the 1970s, according to the U.S.D.A. But that followed an earlier decline.
      • In the late 19th century, Americans consumed nearly twice as much wheat per capita as we do today.
Based on the above findings, the food we eat —wheat and gluten products—alone cannot answer our question. As Dr. Jabri has said, our default response to gluten , is to treat it as the harmless protein as is (i.e., not to respond).[5]


Could It Be the Genes We Inherit?


Active celiac disease can cause severe health problems. you’d anticipate that the genes associated with celiac would be gradually removed from the gene pool of those eating wheat. But, that didn't happen. Scientists have found that:[5]
  • Not only were celiac-associated genes abundant in the Middle Eastern populations whose ancestors first domesticated wheat; some celiac-linked variants showed evidence of having spread in recent millenniums.
    • Reason: the benefits of having these genes (survival) may have outweighed their costs (autoimmune disease).
Perhaps the best support for this idea (i.e., genes is not the culprit) comes from a place called Karelia. It’s bisected by the Finno-Russian border. Celiac-associated genes are similarly prevalent on both sides of the border; both populations eat similar amounts of wheat. But celiac disease is almost five times as common on the Finnish side compared with the Russian. The same holds for other immune-mediated diseases, including Type 1 diabetes, allergies and asthma. All occur more frequently in Finland than in Russia.

WHAT’S the difference? The Russian side is poorer; fecal-oral infections are more common. Russian Karelia, some Finns say, resembles Finland 50 years ago. Evidently, in that environment, these disease-associated genes don’t carry the same liability.

What Could Be the Answers?


Neither the food we eat nor the genes we inherit alone can explain the prevalence of immune disorders found in the past half century. Scientists now suspect that the real problem is that our immune system has simply become overly sensitive. Why?

Could it be that we have lived in a cleaner environment and have been infected with less parasites, bacteria, or viruses? The answer surprisingly could be yes considering the following evidences:
  1. On the Russian side of Karelia, people are poorer and fecal-oral infections are more common. But, they suffer less immune-mediated diseases.
  2. A group of people named Tsimane live on the edge of the Amazon jungle, whose living is still close to Stone Age living.
    • Anthropologists Michael Gurven and Hillard Kaplan who have studied them find that:
      • The prevalence of autoimmune disease is 1/40th what it is in New York City. And parasites are universal. For example, nearly everyone has hookworm.
  3. In 1990s, a Japanese scientist named Koichiro Fujita worked in Borneo. He had also noticed that Bornean children had exquisite skin and no allergies, but they harbored plenty of parasites.
  4. It was established in a case-control study that patients with anti-HAV (i.e., Hepatitis A Virus) antibodies developed reduced frequency of allergic asthma when compared with HAV antibody–negative subjects.[10]
    • Hepatitis A virus spreads by the fecal-oral route.
      • Hepatitis A is spread when human feces contaminates food or when an infected food handler prepares food without appropriate hand hygiene.
Microorganisms and parasites have shared our body space for eons. They are part of our ecological community which could form commensal, symbiotic or sometimes pathogenic relationships with usNow scientists suspect that allergic disease didn't result from excess exposure to allergens, but could be from limited exposure to microbes—especially the ones affect us via fecal-oral route.

It is now widely appreciated that humans did not evolve as a single species, but rather that humans and the microbiomes associated with us have co-evolved as a "super-organism," and that our evolution as a species and the evolution of our associated microbiomes have always been intertwined,
William Parker, Duke University

Living in a cleaner environment, we have managed to remove most of these commensal microbiomes and parasites that might offer a protective mechanism to the immune-mediated diseases. Many scientific theories have been hypothesized to explain this protective mechanism. They include, but not limited to:
  • Th1 and Th2 responses[8]
  • Hygiene hypothesis[9,12]

Summary


For gluten-free diet, we recap as follows:
  • Gluten—a protein found in wheatbarleyspelt, and kamut—could be a toxic protein to some people, which then should be avoided
    • Doctors at Mayo Clinic in Rochester, MN, were surprised to find so many elderly celiac patients with dementia and cognitive decline. A gluten-free diet has been found to help reverse their memory loss and other cognitive problems.
    • Published in the BMJ on 05/02/2017, a new study found that restricting gluten can have harmful health effects on people who don’t suffer from celiac disease.[22]
      • That’s because, according to researchers from Massachusetts General Hospital and Harvard Medical School, going gluten-free means a person reduces their intake of whole grains, which are known to have cardiovascular-health benefits. So, cutting out gluten unless medically necessary can potentially increase a person’s risk of heart problems.
  • It is possible that people develop more gluten issues because of
    • Glyphosate, the active ingredient in the herbicide, Roundup®, could be one of the most important causal factor in this celiac epidemic.  
      • Recently, some researches based on the study of fishes have suggested that glyphosate may interfere with the breakdown of complex proteins in the human stomach, leaving larger fragments of wheat in the human gut that will then trigger an autoimmune response, leading to the defects in the lining of the small intestine that are characteristic of these fish exposed to glyphosate and of celiac patients.[19,20]
    • Impaired digestion and a leaky gut due to a lack of beneficial gut flora[7]
  • A gluten-free or grain-free diet can pose risks if you're healthy[28]
      • If someone is experiencing symptoms that might be related to celiac disease, that person should get tested first, before starting a gluten-free diet.
      • A gluten-free or grain-free diet is not recommended for someone who is not highly sensitive to gluten. Such a diet is also unlikely to provide any benefits.
Video 1.  How to Diagnose Gluten Intolerance (YouTube link)

Photo Credit

References

  1. Is oatmeal gluten-free, or does it contain gluten?
  2. Leaky Gut Syndrome and Autoimmune Disease
  3. "Food that Helps Win the Battle Against Fibromyalgia" by Deirdre Rawlings, N.D., Ph.D.
  4. Gluten-Free Quinoa
  5. The Myth of Big, Bad Gluten
  6. Fibromyalgia misconceptions: Interview with a Mayo Clinic expert
  7. How Does the Gut Flora Influence Our Health?
  8. Th1 and Th2 responses: what are they?
  9. The ‘hygiene hypothesis’ for autoimmune and allergic diseases: an update
  10. Hepatitis A and Allergic Diseases (Travel and Health)
  11. Health Alert – Fatty Liver Disease and Celiac Disease
    • According to the book, "Recognizing Celiac Disease", 3.4% of people with non-alcoholic fatty liver disease have SILENT Celiac Disease.
    • Most patients DO NOT have gastrointestinal symptoms.
  12. he Epithelial Gatekeeper Against Food Allergy
    • Intestinal epithelial barriers play a crucial role in the maintenance of gut homeostasis by limiting penetration of luminal bacteria and dietary allergens, yet allowing antigen sampling via the follicle-associated epithelium for generation of tolerance.
  13. USDA Claims Pesticide Residues in Food Is Safe—Here’s Why They’re Wrong
    • Another reason for the rise of celiac disease
      • Samsel and Seneff's research shows that glyphosate destroys the villi in your gut, which reduces your ability to absorb vitamins and minerals.
  14. The Precautionary Principle (PP) Requires to be Interpreted Critically and Pre-emptively for its Proper Application to the Unique Risks of GM crops
  15. Glyphosate, pathways to modern diseases II: Celiac sprue and gluten intolerance (31 citations)
    • Fish exposed to glyphosate develop digestive problems that are reminiscent of celiac disease.
    • Celiac disease is associated with imbalances in gut bacteria that can be fully explained by the known effects of glyphosate on gut bacteria.
    • In the paper, the authors show that gut dysbiosis, brought on by exposure to glyphosate, plays a crucial role in the development of celiac disease.
  16. Immune homeostasis, dysbiosis and therapeutic modulation of the gut microbiota
  17. How Gluten and Modern Food Processing Contribute to Poor Health (Dr. Mercola)
  18. Increased Prevalence and Mortality in Undiagnosed Celiac Disease
  19. Glyphosate’s Suppression of Cytochrome P450 Enzymes and Amino Acid Biosynthesis by the Gut Microbiome: Pathways to Modern Diseases
  20. Glyphosate, pathways to modern diseases II: Celiac sprue and gluten intolerance
  21. Virus May Be a Trigger to Celiac Disease, Study Says (important)
    • Some viruses (i.e. reovirus ) could be a trigger in a genetically susceptible individual
    • When the viral infection and exposure to proteins like gluten happen at the same time, the immune system gets confused and sees dietary proteins as being dangers
  22. You Shouldn’t Go Gluten-Free Unless You Have Celiac Disease, According to a Study
  23. A glance on celiac disease (Dr. Saad S Al Ani)
  24. Non-celiac gluten sensitivity: literature review.
    • Clinical presentation of NCGS is a combination of IBS-like symptoms (e.g., bloating, abdominal pain, bowel habit abnormalities [either diarrhea and/or constipation]), and systemic manifestations (e.g., foggy mind, headache, fatigue, depression, joint and muscle pain, leg or arm numbness, dermatitis [eczema or skin rash], and anemia)
  25. Celiac Disease and Nonceliac Gluten Sensitivity—A Review
  26. Unraveling the Mystery of Gluten
  27. Gluten-free diet (Mayo Clinic) 
  28. Is There a Downside to Going Gluten-Free if You’re Healthy?
  29. It’s Not All in Their Heads: Non-Celiac Gluten Intolerance’s Immunologic Basis (Cleveland Clinic)
  30. Allergy or Intolerance: How Can You Tell the Difference?

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