Anti-Inflammatory Diet

All health care starts with diet. My recommendations for a healthy diet are here:
Anti-Inflammatory Diet and Lifestyle.
There are over 190 articles on diet, inflammation and disease on this blog
(find topics using search [upper left] or index [lower right]), and
more articles by Prof. Ayers on Suite101 .

Wednesday, June 29, 2011

Soluble Fiber: Food for Gut Flora

The human body only produces enzymes to digest proteins, fats, starch and a few simple sugars. The remaining components of food either pass through the intestines undigested (insoluble fiber) or are digested by bacteria and fungi in the colon (soluble fiber.) Soluble fiber feeds gut flora. Insoluble fiber is usually minimized by traditional food preparation, for example grains, because it contains unhealthy materials, such as phytic acid. Soluble fiber is healthy and required for normal development of the gut/immune system, whereas insoluble fiber should be avoided.

Soluble Fibers in Vegetables are Carbohydrates/Polysaccharides

Plant cells are surrounded by cell walls composed of long chains of sugars, polysaccharides. These wall polysaccharides, e.g. pectin, arabinogalactans, xyloglucans, and storage glucans and fructans, are highly complex in structure and can only be digested down to simple sugars by the action of dozens of different enzymes produced by dozens of different bacterial species in the colon. Many plants (as well as fungi and bacteria) also produce unique polysaccharides that are only susceptible to additional unique bacteria enzymes. Thus, digestion of diverse vegetables requires hundreds of different species of bacteria in the gut. Healthy gut flora consists of more than 150 different species of bacteria, which were eaten with food and adapt to the gut environment.

Food Intolerances/Most Food "Allergies"/Constipation Reveal Missing Enzymes

Enzymatic treatment of complex polysaccharides in the gut is a complex process that also yields many intermediate products that can influence both gut flora and the gut itself. A well adapted gut flora can systematically digest most of the food molecules that pass into the colon and produce only short chain fatty acids (CFAs) that feed the colon and pass through the liver to the rest of the body.

Antibiotics or a history of limited food choices and excessive hygiene can result in a simplified gut flora that only partially digests soluble fiber and results in accumulation of unusual byproducts that irritate the gut, and cause bloating and gas. Adverse reactions are called food intolerances or food allergies. Since bowel stools are composed predominantly of loosely packed gut flora, inability to fully digest and convert soluble fiber into more gut flora, also results in constipation.

Soluble Fiber in Meat is also Polysaccharide

Meat is made of fibers of protein connected to bone by polysaccharides. The tendons, gristle and other chewy parts of meat are made of chondroitin sulfate and other glycosaminoglycans (GAGs). Heparin is another GAG, which is released onto the surface of the intestines to block the adhesion of viruses and pathogens to the gut, and is subsequently digested by colon bacteria. Other components of meat (and vegetables), such as nucleic acids and some fats are also digested by enzymes of the gut flora. The versatility of gut flora to adapt to a huge variety of foods permits people to live on very diverse diets, ranging from vegan to paleo.

Modern Diets Starve and Simplify Gut Flora

Modern diets consist of processed foods that are made of fat, protein and starch, all of which are digested and absorbed before reaching the colon. These simplified foods produce a simplified gut flora that may also produce more CFAs rather than stool forming gut bacteria. In other words, eating larger amounts of simpler foods can result in more of the nutrients being absorbed and making it easier to gain weight on less food with a tendency toward constipation. These diets may also select for bacteria that maintain the simplified, "efficient" gut flora community and provide the potential for the spread of obesity through a population. Having friends and relatives who are obese and presumably have gut bacteria that favor obesity, increases the risk of obesity. It seems likely that obesity is contagious.

Simplified Gut Flora also Means a Compromised Immune System

Complexity in the gut flora is also needed to produce a healthy immune system, because different species of bacteria in the gut stimulate the development of different parts of the immune system, which develop in the lining of the gut. Soluble fiber is the normal food for the colon bacteria that control the part of the immune system that regulates autoimmunity and allergy, for example. Obesity is also associated with increased risk of degenerative and autoimmune diseases, which is consistent with defects in the gut flora that reside in the colon. Thus, the modern high carb diet contributes to the symptoms of obesity by elevating blood sugar, blood CFAs, as well as compromising the gut flora needed for normal functioning of the immune system.

Healthy Gut Flora = Anti-Inflammatory Diet + Eating New Bacteria

A damaged or simplified gut flora can be fixed by eating foods that supply nutrients for the body as well as feeding the gut flora, e.g. plenty of different types of soluble fiber. It is also necessary to eat the missing bacteria. Just adding a few probiotics with yogurt will not fix the problem and cooking kills all of the good bacteria. Fermented foods, especially those based on bacteria from your own home and garden, are good sources of health-providing bacteria. Raw vegetables will also provide bacteria that may be useful in your gut flora, as long as the vegetables are not too thoroughly washed. Sterilizing and cooking vegetables may avoid rare pathogens, but will certainly prevent contributions to a healthy gut flora.

Tuesday, June 14, 2011

Food Poisoning and Manmade E. coli

Bacteria on food is a problem for diet-compromised people.   
Gut Flora are Required for a Healthy Immune System
Healthy people don't get sick from food poisoning, because their gut flora provide protection.  Gut bacteria control the development of the human immune system by producing interesting compounds, including short chain fatty acids and vitamins.  In response to the gut bacteria, the healthy immune system produces white blood cells that can effectively attack bacteria, and also control this aggressive behavior to spare human cells and avoid unnecessary attacks on beneficial bacteria.
Disrupted Gut Flora Lead to Susceptibility to Disease/Infection
Gut flora can be compromised by what we eat and antibiotics.  Those normally affected by food poisoning are the very young (on formula), the old (constipated) and those treated with antibiotics.  Each of these groups have abnormal gut flora.  Food poisoning is rarely observed in exclusively breastfed babies being introduced to foods, because human milk contains potent antimicrobial polysaccharides (human milk oligosaccharides) that only permit the growth of a few species of Bifidobacteria.  Formula (in any amount) disrupts the normal development of the gut and immune system by stimulating an inflammatory growth of adult gut bacteria, making these babies more susceptible to intestinal and respiratory diseases, including food poisoning.
Constipation, which is more common in older people, reflects a disruption of the gut flora and decreases the effectiveness of the immune system in these individuals.  In most cases the compromised gut flora results from a long history of a restricted diet and  reduced access to environmental sources of bacteria.
Antibiotics are usually ignored as major corruptors of the immune system, even though they are known to produce diarrhea and constipation.  Doctors reluctantly suggest that people taking antibiotics should just eat some yogurt.  This is a silly oversight that severely compromises future health, because probiotics supply only a tiny fraction of the 150 different species of bacteria needed for a healthy body and immune system.
Pathogenic E. coli is Made by Antibiotic Use in Cattle
E. coli is a common and essential resident of the human gut and the best studied bacterium.  This bacterium is not normally resistant to antibiotics nor does it produce deadly toxins.  Antibiotic resistance and toxin production results from treating cattle with antibiotics to increase fat production prior to butchering.
Antibiotics Select for E. coli that Stick to Rectal Surface of Cattle
Pathogenic E. coli are not found throughout cattle fecal material, but rather they are only in the outermost surface layer.  This outer layer of material contains bacteria from the surface of the rectum just as the cow pies are deposited.  E. coli does not normally stick to this surface, because it lacks a protein, such as a hemagglutinin capable of binding to the surface polysaccharides, heparan sulfate.  Antibiotics kill off the bacteria normally residing on the surface.  As a member of the intestinal biofilm community, E. coli continually exchanges DNA/genes with other bacteria in the gut and picks up three useful genes, to become a pathogen:
  1. Antibiotic resistance
  2. Hemagglutinin for sticking to surfaces
  3. Toxin to release nutrients from the intestinal walls.
E. coli with these three genes can colonize the rectal tissue of cattle in feed lots.
Pathogenic E. coli Can be Easily Avoided
We have to work hard as a society to have problems with E. coli.  Pathogenic E. coli results from absurd use of huge quantities of antibiotics just to disrupt the normal gut flora of cattle so that they become unhealthy and store fat in their tissues, i.e. prime beef.  The same effect can also be achieved just by feeding the cattle some short chain fatty acids, or better still avoiding this step by feeding exclusively on grass.  It would also be easy to treat the few cattle that have pathogenic E. coli, so that it doesn't become a problem.  Proper treatment of manure and meat processing would also block transmission of pathogenic E. coli to agricultural crops or meat.  Finally, an Anti-inflammatory Diet and Lifestyle would provide a healthy gut flora and immune system that would make people less susceptible to the pathogen.

Thursday, June 9, 2011

Udder Nonsense

Recent articles in the popular press have heralded the genetic engineering of cows with some human milk proteins.  Milk produced by these transgenic cows is advertised as being similar or the same as human  breast milk.
This is like claiming that the udder in the picture is an all natural, low BPA container for fortified water.  

The breakthrough in humanized cow's milk, announced by Chinese researchers in PLoS One, actually documents replacement of cow lysozyme with the corresponding human enzyme.  That does not make the milk human anymore than adding egg white lysozyme would turn the cows into chickens. If it moos like a cow...
Cow's milk-based formula harms infants, because the carbohydrates it contains do not support the normal development of infant gut flora.  The result is gut inflammation, and not normal gut and immune system development.  Even human proteins produced in cows will have characteristic cow sugars attached.  It is these cow sugars on milk proteins that are associated with colic. The chains of sugars (milk oligosaccharides) free and/or associated with milk proteins are different in cows and humans, and cow carbs are a problem in formula.
I think that it is silly to support humanizing cow's milk formula, when the sensible solution is to support breast feeding and licensed human milk banks.  The natural approach is much cheaper and far healthier.  Only human milk and human milk-derived fortifiers should be used for infants (especially preterm) in hospitals.  It is time for the healthcare industry to realize that disruption of gut flora by antibiotics or artificial formula is a health risk.  The data are clear -- cow's milk (including transgenic cow’s milk) in the hospital may be profitable, but it is unhealthy, e. g. contributes to Clostridium difficile and necrotizing enterocolitis infections, and contributes to long term health problems, such as inflammatory and autoimmune diseases.

Wednesday, June 1, 2011

Contagious Health

Healthy gut flora: bacteria from family, friends, Fido and food provide the foundation for the complex microbial community of the intestines, which controls the immune system.  Antibiotics and hygiene are detrimental to gut flora and health.
Gut Flora Are Complex
Recent studies of the gut flora, e.g. the human gut biome, show that each individual maintains more than 150 different species of bacteria.  Worldwide, that means that about a thousand different bacterial species are common residents of the human gut and together those gut bacteria use more than 1 million different genes.  Many of those genes code for the enzymes used by gut bacteria to digest plant polysaccharides, i.e. soluble fiber.
Hygiene Isolates People from Healthy Sources of Gut Flora
Every time we speak, we release a mist of bacteria from our lungs, mouth and GI tract.  These bacteria are on our skin, clothes and personal items, and provide a source of the bacteria that make us healthy.  Parents and older siblings pass these bacteria on to younger children.  These donated bacteria are essential for the development of a healthy immune system and children growing up with healthy relatives and exposed to soil bacteria via pets, farm animals, etc. are healthier than children who are more isolated.  
In this sense, hygiene is unhealthy, because an individual is isolated from new sources of bacteria that could replace those lost by limited diets, antibiotics, etc.  Otherwise, health is contagious, since gut bacteria from healthy individuals can spread among the population.  Washing hands and food is unnatural and unhealthy.
Few Bacteria Make You Sick, but Many Are Essential for Good Health
Food intolerance can result from “good” family hygiene, limited diets and exposure to antibiotics.  A common intolerance results from the absence of bacteria that produce an enzyme to digest dairy lactose, i.e. lactose intolerance.  Lactose intolerance can be readily cured by eating a dairy product, such as yogurt, that contains both lactose and live bacteria (probiotics) that can digest the lactose.  Simply eating moderate amounts of live yogurt daily for a couple of weeks resupplies the gut flora with bacteria that can digest lactose, and the intolerance is gone.
Soluble Fibers Are Plant Polysaccharides that Are Digestible by Bacterial Enzymes
Humans only produce enzymes to digest one polysaccharide, starch.  All of the other hundreds of polysaccharides present in plants are only digestible by bacterial (and fungal) enzymes of the gut flora.  If the bacteria and enzymes needed to fully digest a particular food polysaccharide are absent, then digestive problems ensue and the polysaccharide can act as a laxative.  Continual eating of the problem food with a new source of diverse bacteria, e.g. lightly rinsed vegetables right from the garden, then the gut flora will incorporate new bacteria that can digest the problem polysaccharide and the gut is happy.  
Soluble fiber feeds the gut bacteria that convert it into short chain fatty acids that nourish the colon. Constipation results from the absence of the bacteria needed to digest dietary fiber and to produce the large volume of bacteria that make up well hydrated stools. 
Gut Bacteria Are Needed for Healthy Immunity
Cells of the human immune system are stored predominantly in the lining of the intestines.  Intensive study of the interaction of the gut bacteria with the gut has revealed that both the aggressive half of the immune system that attacks pathogens and the suppressive half that protects the body itself from attack, develop in the gut in response to particular types of bacteria.  Thus, the absence of one type of bacteria can cripple responses to infection, while other bacteria are needed to block autoimmune diseases and allergies.  Most diseases are caused by disruption of the normal interactions between gut bacteria and the immune cells developing in the gut.
Antibiotics Lead to Autoimmunity
Antibiotics have dramatic and lasting impact on gut flora.  Cattle treated with antibiotics and a high carbohydrate diet have an altered metabolism (obesity) that leads to rapid fat accumulation in their tissues.  This is good for making tasty beef, but the same approach in people produces the suite of diseases in affluent societies.  
Children treated with an antibiotic for a simple ear infection, are much more likely to return to pediatricians for treatments of subsequent obesity, infections and diseases.  Compromised gut flora can take years to return to normal function after antibiotic treatment.  Loss of the appendix, which is the normal source of bacteria to replenish gut flora after diarrhea, results in an increased risk of abnormal gut flora and numerous autoimmune diseases.  It is likely that most autoimmune diseases are preceded by prior treatment with antibiotics that disrupted normal gut flora and permanently altered the immune system.
Interventions to Treat Disease:  the Anti-Inflammatory Diet and Fecal Transplants
It should be obvious that a disrupted or unhealthy gut flora will compromise the immune system and contribute to disease.  Treatment of diseases is complicated by the use of drugs that also impact the gut flora and produce additional side effects.  An alternative approach would be to support the healthy gut flora and normal development of the gut immune system.  As always, the answer is a supportive diet and a source of gut bacteria.  The diet is obviously the Anti-Inflammatory Diet that provides support for almost anything that ails you.  Probiotics are not retained in the gut, but they can contribute a few of the genes needed for a healthy gut flora. The source of bacteria for a  healthy gut flora may range from minimally washed garden vegetables, to the more aggressive total replacement of gut flora with a fecal transplant from a healthy donor.