Genetics of Food Intolerance

Food intolerance is based on missing bacteria in the the gut rather than inadequacy of human enzymes, e.g. lactase, or altered immune system.

I make the extreme statement that food intolerance is not genetic, to emphasize that the vast majority of intolerance can be cured by changing the bacterial composition of the gut's microbiological community, the gut flora, rather than attempting to accommodate a permanent deficiency. The two common "intolerances" that are offered by my readers to invalidate my sweeping statement are lactose and gluten (celiac) intolerance.

Lactose Intolerance is Not Due to Inadequate Lactase
Everybody has the same gene for lactase, but some people have altered upstream control elements and continue to express lactase in their intestinal cells after infancy, whereas others don't. The racial pattern of adult lactase expression is an interesting note on human evolution, but is irrelevant with respect to an individual's ability to tolerate the lactose sugar in dairy products.

Lactose is the major sugar present in milk and the ability of the intestines to utilize lactose directly like glucose is a selective advantage for human evolution. Absent that ability, lactose would just pass through the gut without impact. However, bacteria in the colon also have lactose digesting enzymes. These bacteria produce hydrogen and methane gases, and these products in turn can feed other bacteria. If all of the products are consumed, then the lactose has been treated as a soluble fiber and the result is more gut bacteria and a happy gut. If some of the bacteria are missing, then the lactose acts as a laxative, e.g. lactulose, and the bowels are not so happy.

All that is needed to cure lactose intolerance, as in all food intolerances, is to provide the gut bacteria that are missing to fully metabolize the offending sugars or polysaccharides. Just continuing to eat dairy without also eating or introducing new species of bacteria into your gut, will just provide more symptoms, but eating yogurt still containing live probiotic bacteria (Read the label. Any live bacteria listed will work.) that have the enzymes to ferment lactose, will lead to a rapid cure. (See reference below.) As the fermenting bacteria grow in the gut, they transfer their genes to gut bacteria in the biofilms lining the gut and these new species of bacteria keep the lactose out of trouble.

The point is that having a food intolerance means that the aggregate of all of the genes in all of your gut microorganisms is lacking the genes/enzymes needed to completely digest a food component. In the case of lactose intolerance, the missing genes are present in typical probiotics, bacteria that grow on milk/lactose.

Celiac is not a Typical Food Intolerance
Celiac is a complex interaction between major toxic proteins in wheat (gliadin), detox gut enzyme (tissue transglutaminase, tTg) and antibodies. Gliadin is a wheat protein adapted to attack the intestines of herbivores. Herbivores, such as insects and humans, can in turn protect themselves from gliadin and other polyglutamine proteins with the enzyme transglutaminase. tTg binds to glutamines in gliadin and converts them to glutamic acids. Unfortunately, while the gliadin is bound to the tTg, inflammation can predispose the gut to present these proteins to the immune system for processing to trigger antibody production. This is the start of the autoimmune disease.

The major histocompatibility antigens (MHAs) code for the proteins that display fragments of proteins on cell surfaces for antigen presentation and immune response. There is a lot of MHA variation and evolutionary adaptation. Some MHAs favor antibody production to gliadin and tTg. This just shows that celiac and grain/gluten intolerance is not a typical food intolerance, which will be remedied by simply altering gut bacteria, even though establishing gut bacteria that metabolize gliadin or that reduce autoimmunity, may be part of the cure.


Enhancing Gut Flora is Part of the Cure for all Autoimmune Diseases
There are rare food allergies, even though the majority are misdiagnosed intolerances. The production of antibodies to food antigens is a symptom of the breakdown in communication between the gut immune system and gut flora. Particular species of bacteria are responsible for the development of both the aggressive and suppressive components of the immune system, which occurs in the lining of the gut. Loss of the suppressive cells, Tregs, can result from unhealthy diets and exposure to antibiotics, and results in autoimmune disease, in which the aggressive immune system is out of control and attacks self antigens.

Symptoms of all autoimmune diseases can be improved by reestablishing normal control of the aggressive part of the immune system via healthy gut flora. Clostridium species of bacteria normally induce healthy development of the suppressive immune system and these types of bacteria are common in soil clinging to fresh vegetables prior to extensive washing. Which of the bacteria that are eaten become established in the gut flora is unpredictable, because the bacteria interact with each other, food and cells lining the gut. The only safe and simple procedure currently available is the fecal transplant. Some experimental fecal transplants are facilitated by the use of encapsulated freeze-dried gut flora. There is great resistance to this simple, safe, cheap approach from the medical industry.

Reference:
Almeida CC, Lorena SL, Pavan CR, Akasaka HM, Mesquita MA. 2012. Beneficial Effects of Long-Term Consumption of a Probiotic Combination of Lactobacillus casei Shirota and Bifidobacterium breve Yakult May Persist After Suspension of Therapy in Lactose-Intolerant Patients. Nutr Clin Pract., 27(2):247-51.

Dr. Oz, Vitamins, Biofilms

Vitamins supplement enzyme action, but they are produced by gut flora for biofilm communication.

Dr. Oz and the general biomedical community promote the idea that vitamin supplements or in foods are needed or improve health. Of course, several research studies show that typical multivitamin supplements or the levels of vitamins in "enriched" foods do not provide improvements in health. Since gut flora produce all of the needed vitamins, this should be no surprise. But why do gut bacteria release vitamins needed for the normal functions of the human body?

Vitamins are Enzyme Cofactors

Vitamins are small molecules that bind to particular cellular enzymes and provide functions that can't be provided by proteins. Enzymes are linear strings, polymers, of about a thousand amino acids. The 23,000 human genes code for the sequence of amino acids in as many enzymes. The amino acid strings fold up systematically into three dimensional balls that bring together chemical groups of the amino acids that can catalyze biochemical reactions. The twenty different amino acids in proteins are limited in the scope of their reactions. Binding of some metabolic products, such as vitamins, expands the types of reactions possible. Vitamins are enzyme cofactors. Bacteria can synthesize all of the vitamins needed for metabolism, but humans can't.

Vitamin D is a Hormone

Vitamin D is not a typical vitamin.  It is not an enzyme cofactor, but rather it is a steroid hormone that is produced in the skin from cholesterol through the action of ultraviolet light. The production of antibacterial peptides in the small intestines, for example, is a response of intestinal cells to vitamin D. Exposing arms and legs to sunlight produces about 10,000 IU of vitamin D per minute. (Typical supplements contain only 1,000 IU.) Production of vitamin D is reduced by skin pigmentation, sunscreen and inflammation. People exposed to daily sunlight for hours in San Diego, for example, may still be deficient in vitamin D, if their production of vitamin D has been shut down by chronic inflammation, as indicated by typical inflammatory conditions, such as arthritis, allergies, inflammatory bowel diseases, obesity, dental/oral infections, prostatitis, thyroiditis and other autoimmune diseases.

Vitamins are Produced by Gut Biofilms

People with healthy, diet-adapted gut flora, can subsist on very limited diets without vitamin deficiency diseases, because all of the vitamins can be obtained from bacteria growing in films coating the lining of the gut. These biofilms are complex communities of dozens of different bacteria and fungi. The bacteria synthesize polysaccharides in which these and other bacteria and fungi become embedded. The biofilms release vitamins that are taken up by intestinal cells to provide the needs of the body.

Vitamins are Chemical Signals for Biofilm Assembly

Bacteria, such as E. coli, do not form biofilms, if they are just grown at low concentrations on laboratory nutrients. If the concentrations of bacteria become very high, however, the bacteria respond by activating genes that coordinate biofilm formation. Bacteria detect the presence of other bacteria by releasing and detecting chemical signals in a process called quorum sensing. The chemical signals used in quorum sensing and biofilm maintenance are vitamins. Thus, human intestines are adapted to exploit the presence of biofilms and vitamin secretion. Humans need not synthesize vitamins, because they are always produced by gut biofilms as an essential biofilm function.

Antibiotics and Multivitamin Supplements

Antibiotic use is known to disrupt gut flora and produce vitamin deficiencies. Killing off healthy gut biofilms with casual use of antibiotics should be anticipated. The medical industry is remiss, however, in not repairing gut flora after medically mandated antibiotic use. Probiotics can temporarily supply some of the functions of the hundreds of bacterial species in each healthy individual, but they do not replace complex biofilms.

 The vitamin production of some of the bacterial species eliminated from the gut by antibiotics can be replaced by vitamin supplements, but supplements may disrupt the normal vitamin/quorum sensing communication and further disrupt biofilms. Thus, vitamin supplements may be unhealthy, if they disrupt biofilms that are necessary for healthy function of the gut-based immune system, which is needed to avoid, for example, allergies and autoimmune diseases.

Major Points about Vitamins, Biofilms and Health

• Health requires gut biofilms to supply vitamins and control the immune system.
• Biofilms produce and use vitamins for maintenance of biofilms.
• Eating vitamins may disrupt normal biofilm formation.
• Antibiotics disrupt gut biofilms and cause vitamin deficiencies and immune system disfunction.
• Biofilm repair requires ingestion of missing bacterial species (150 total) and may be inhibited by excessive hygiene.