Tag Archives: intestinal permeability

Why do our tax dollars continue to subsidize death, disability and disease?

Yesterday I posted a comment on Medscape after reading an article Longtime Dietary Fat Advice Unsupported by Data: Analysis . Medscape is a website with articles and news written for physicians and other health professionals. Anyone can access this information by creating a user name and password, there is no fee.

Here is my comment. It is long and technical. I will provide an explanation in lay terms after quoting myself.

Sugar, especially HFCS (high fructose corn syrup), used in so many foods is more inflammatory than saturated fat. Grass fed meat from ruminants has a fatty acid mix that is exactly the same as wild game, which we evolved to eat, along with tubers, green leafy vegetables, and fruit in season. Excess refined fructose intake AND use of modern refined “vegetable oils” along with non-healthy grains combine to cause excess caloric intake, NAFLD (non-alcoholic fatty liver disease), obesity, metabolic syndrome and CAD (coronary artery disease). N6 PUFA (omega six polyunsaturated fatty acids) are easily oxidized. N3 PUFA (omega 3 fatty acids) despite greater number of double bonds are protected from oxidation in cell and Lipoprotein membranes by plasmalogens as opposed to linoleic acid which is not easily  incorporated into plasmalogens. The PUFA in vegetable oils (linoleic acid) is the FA (fatty acid) that is oxidized on LDL particles and remnant particles, stimulating monocytes to transform to macrophages and then foam cells. The USDA, ADA and AHA have had it upside down for decades and they still fail to admit folly. We evolved for > 1 million years without grains and they have contributed to disease. Per calorie fresh vegetables have five times the amount of fiber compared to whole grains. We do not need grains and would be better without them. They contain anti-nutrients and wheat, hybridized in the 1980s to a storm resistant dwarf plant, now has 50 times more gluten/gliadin than the old wheat. This has generated more gluten intolerance and celiac. Our greatest nutritional threats to public health include refined sugar, carbohydrates predominantly from grains and refined vegetable oils. Vegetable oils are not healthy, we did not evolve to eat them. N3 FAs are anti-inflammatory but have been competing in our diets with a sea of inflammatory N6 PUFA from unnatural refined and easily oxidized “vegetable oils”. Even though PUFA can reduce LDL-C they wreak havoc by creating ox-LDL particles which initiate the cascade of atherosclerosis. Substituting SFA (saturated fatty acids) with PUFA results in increased levels of Lp(a) and oxLDL in humans, not a good thing. Close the feed lots, stop government subsidy of corn, wheat, dairy and soy, eat meat from grass fed ruminants, wild seafood, fresh organic vegetables and fruits in season. Nibble on tree nuts. Stop creating carcinogens with high dry heat cooking methods and we will watch obesity, insulin resistance, metabolic syndrome and atherosclerosis melt away.

That was my comment. Here is some explanation.

I have previously discussed the pro-inflammatory nature of refined “vegetable oils”. “Vegetable oils” are actually not from vegetables, they are from grains, seeds and legumes. The two major sources of excess omega six polyunsaturated fats in the American diet are corn oil and soy oil marketed by various brand names such as Wesson. They are major components of margarine and other butter substitutes and are present in most salad dressings. Most salad dressings sold in our supermarkets contain high levels of easily oxidized unhealthy refined “vegetable oils” and HFCS. The use of these salad dressings converts a healthy salad into a vector for disease.

The major source of caloric sweeteners in our food and beverages is high fructose corn syrup. Both corn (oil and sugar) and soy predominate our processed food supply because they are cheap. They are cheap because our tax dollars subsidize their production. This subsidy started during the Nixon administration. Once a food subsidy is put in place it is very difficult to eliminate, Big Agriculture provides a deep pocket for lobby money and our elected officials from the mid-west bread-basket respond to $$.

Another major source of disease causing elements in the standard American diet is highly refined flour from wheat. Doctors Davis and Perlmutter discuss the problems associated with wheat-flour foods in their books Wheat Belly and Grain Brain respectively. The production of wheat has also been subsidized since the Nixon administration.

Wheat is not what it used to be. A new dwarf hybrid wheat has predominated the US market since the 1980s. Bread and pasta are not what they used to be when great grand-mother made her own bread and pasta in the kitchen from coarsely ground whole flour. But even if we all went back to making our own whole-grain bread and pasta from locally ground pre-1980s wheat, bread, pasta and pastry would still present a health risk because of issues related to intestinal permeability, auto-immune disease (now epidemic in the USA), and the presence of nasty lectins and phytates (discussed in my manifesto and previous posts).

The Medscape comment quoted above describes  adverse consequences caused by replacing saturated fat in the diet with “vegetable oils”. This is a complex subject and I will try to be brief for now but promise to expand on this in a future post.

Many factors contribute to atherosclerosis, heart attack and stroke. Sedentary lifestyle, stress, inadequate restorative sleep, smoking and poor dietary choices top the list. These factors also contribute to obesity, diabetes, metabolic syndrome, insulin resistance and many cancers.

DIETARY FACTORS:

The combination of sugared foods and beverages (predominantly sweetened with HFCS), refined flour foods, and excess consumption of the PUFA in “vegetable oils” TOGETHER  contribute to the formation of plaque in the walls of our arteries (atherosclerosis).

How does this happen?

LDL (low density lipoprotein) is a particle that transports cholesterol and triglycerides through our blood to our organs. This particle is comprised of a core and a surrounding membrane.  Here is a picture.

LDL 2

The core contains cholesterol in a storage form (esters) and triglycerides. The outer membrane includes a large protein called apoprotein B-100, “free” cholesterol molecules and phospholipids. The phospholipids contain fatty acids, including PUFA.

LDL has been demonized as “the bad cholesterol” and that demonization has mislead the public.

hdl_ldl good guy bad guy

LDL is the major lipoprotein in our blood but there are others that have different names.

Cholesterol is cholesterol, whether it is carried in LDL or HDL. When carried in the core of a lipoprotein it is carried as a cholesterol ester. 80% of the cholesterol in an LDL particle is carried as an ester in the core. 20% is carried as “free” cholesterol on the outer surface or membrane.

LDLand cholesterol molecule

HDL (high density lipoprotein) is smaller and denser. HDL has been called “the good cholesterol”, another misnomer.

HDL particles, when they are functioning correctly can protect us from atherosclerosis but in patients with diabetes, obesity, and insulin resistance, HDL particles do not function well and in fact probably contribute to disease. (More about that in a future post)

But back to LDL.

Although the risk of cardiovascular disease is correlated with the amount of cholesterol carried by LDL in our blood (referred to as LDL-C), the total amount of cholesterol shuttled by LDL particles is much less relevant than one would be led to believe given the great use of statin drugs to lower LDL-C.

The short version is as follows.

Compared to LDL-C, a much better predictor of cardiovascular disease is the amount of “modified” LDL particles circulating in the blood. Oxidized LDL particles are one form of “modified LDL”. LDL can also  be modified by excess blood sugar levels (especially from HFCS). This modification is referred to as glycosylated or glycated LDL. In this latter form of modification, the major protein on the outer membrane of the LDL particle (apo B 100 in the picture above) becomes attached to a sugar and the result is an LDL particle that is not easily cleared by normal processes. The modified LDL is not “recognized” by the LDL receptors that act as entry points into our cells for proper processing. The result is that the glycated LDL particles circulate longer and are more likely to use up their anti-oxidants (Vitamin E and  Co-enzyme Q 10).

As a result glycated LDL are more likely to become oxidized. That is not good because oxidized LDL sets up a cascade of unhealthy events.

The portion of the LDL particle that becomes oxidized is the fat (fatty acid) from “vegetable oil”, specifically the fatty acid called linoleic acid. This fatty acid has two double bonds making it more likely to be oxidized than for example oleic acid, the major fatty acid in extra virgin olive oil which has only one double bond.

The double bonds between the carbons in the fatty acids are unstable and easily oxidized. The single bonds in saturated fat do not get oxidized.

All other things being equal (and you will see that they are not), the more double bonds in a fatty acid the greater chance for oxidation.

Here is a picture showing the linoleic acid, also called linoleate, on the outer membrane of the LDL particle.

LDL with linoleate

And here is a picture that shows the phospholipids that contain the linoleic acid.

LDL 3

Let’s say it again. The fatty acid found in “vegetable” oil, linoleic acid, is easily oxidized because it has two double bonds.

Saturated fats are not oxidized because they contain no double bonds.

The part of the LDL particle that becomes oxidized is the fatty acid that comes from “vegetable oils”.

A particular kind of immune cell (white blood cells called monocytes) have  special receptors for oxidized LDL particles. When ox-LDL are “seen” by these monocytes, the monocytes become transformed into macrophages. Macrophages are designed to destroy bacteria that invade our bodies. The oxidized LDL particles resemble the structures of invading bacteria. The macrophages, with very specialized receptors for oxidized LDL, “swallow” the LDL particles and release toxic chemicals to destroy “the invader”.  The macrophages then become “foam cells” in the walls of our arteries, initiating the creation of plaque. Here is a picture.

ldl_mechanisms oxidation in vessel wall

This picture depicts the oxidation occurring in the wall of the artery after LDL particles have penetrated the wall. However LDL particles can and do become oxidized while still circulating in the blood and these oxidized particles can stimulate monocytes to transform into macrophages and gobble up the oxidized or modified LDL while these particles are still circulating in the blood.

How and whether unmodified LDL particles cross the wall of arteries into the “sub-endothelial” area remains an unsolved complex issue. The picture above implies that LDL particles simply move across the endothelial cells that line the wall of the artery but that is a presumption.

Clearly, macrophages that have “swallowed” modified LDL particles have mechanisms to work their way between the junctions formed by adjacent endothelial cells.

This is an important distinction because many cardiologists believe that what drives atherosclerosis is a mass effect. The greater the number of LDL particles, the more likely they are to cross the endothelial barrier, get oxidized and retained and start the process of plaque formation. However the process is much more complex and not clearly understood.

We do not yet know or understand completely the factors that influence the permeability of the endothelium to Lipoprotein particles. We do know that modified (oxidized and glycated LDL) disrupt the protective surface of endothelial cells which is called the glyocalyx. Other factors that disrupt the glyocalyx include high blood sugars, dramatic fluctuations in blood pressure (too high or too low), oxidative stress, infections, and circulating endotoxin (which is governed by intestinal permeability).

It is clear from several studies that modified (oxidized) LDL as a single variable predicts cardiovascular disease and heart attacks with much greater accuracy than LDL-C (total cholesterol content of LDL particles). It is also clear that monocyte receptors are specific for modified LDL and that the  process that initiates the cascade of events that leads to plaque formation involves the interaction between modified lipoprotein particles and the immune system (monocytes).

Now here is another twist.

Omega 3 fatty acids in fish oil are considered “heart healthy”. They help prevent heart attacks and strokes. They also decrease inflammation throughout the body thereby producing many health benefits.

BUT OMEGA 3 FAT HAS MORE DOUBLE BONDS THAN OMEGA 6 FAT (LINOLEIC ACID) YET THEY HELP PROTECT THE HEART. HOW CAN THAT BE?

How do they avoid contributing to atherosclerosis? Are they not even more readily oxidized than linoleic acid?

The simple answer is no.

The major reason is that the omega three fatty acids are protected by “plasmalogens” which are important components of our LDL particle outer membranes. Plasmalogens are found in the membranes of lipoprotein particles and in the membranes of human cells. Because of their chemical structures, omega three fats are easily incorporated into plasmalogens which protect the double bonds of omega three fats from oxidation. Linoleic acid, the predominant component of “vegetable oils” is not easily incorporated into the protective arms of plasmalogens.

This selective protection is well described on pages 141-142 of  “The Fats of Life”, written by Dr. Glen Lawrence and published in paperback in 2013. (link below)

I asked Dr. Lawrence about this issue in an email and here was his response.

“The omega-3 fatty acids are preferentially incorporated into plasmalogens, which act as antioxidants due to the double bond adjacent to the ether linkage of these phospholipids. This structure would tend to scavenge free radicals or reactive oxygen species near the surface of the membrane, rather than allowing them to penetrate deeper in the membrane where the double bonds of PUFA are located. This makes any polyunsaturated fatty acids attached to the plasmalogens more resistant to oxidation than they would be in a regular phospholipid. See pp 141-142 of The Fats of Life. The shorter chain and less unsaturated linoleic acid does not tend to be incorporated into plasmalogens.”

In summary:

  1. “Vegetable oil” is actually not oil from vegetables but rather a highly processed and refined oil. This oil contains primarily the easily oxidized omega 6 PUFA (polyunsaturated fatty acid) linoleic acid. Oxidation can occur during manufacture,  before consumption while sitting in the bottle, but especially during high heat cooking (fried foods). Oxidation can also in your body as this fat circulates in your blood on the membrane of lipoprotein particles.
  2.  LDL particles are the major lipoprotein particles that shuttle cholesterol and fatty acids (in in the form of triglycerides) through our bodies in our bloodstream.
  3. Modified LDL particles (glycated and/or oxidized LDL) stimulate monocytes (immune cells) to transform into macrophages and gobble up the modified LDL. In addition, glycated LDL particles are more easily oxidized because they circulate longer in our blood.
  4. Macrophages become filled with modified LDL. These are called foam cells. Foam cells  initiate a cascade of events that lead to the formation of plaque in the walls of our arteries.
  5. The part of the LDL particle membrane that becomes oxidized is the phospholipid that contains linoleic acid which comes from “vegetable oils”
  6. High amounts of sugar, especially HFCS, and highly refined flour foods in our diets cause larger blood sugar fluctuations than whole foods and therefore contribute to the glycation of LDL particles. This glycation leads to more oxidation of LDL. In this manner HFCS and refined flour foods contribute to the process of atherosclerosis.
  7. High amounts of sugar, HFCS and refined flour foods also contribute to obesity, insulin resistance and diabetes which then increase the risk of heart attack and stroke.
  8. Several factors contribute to the disruption of the glycocalyx which is the protective surface of the endothelial cells that line our arteries. These include but are not limited to modified LDL, inflammation, high blood sugars, abnormal fluctuations in blood pressure, circulating endotoxin (associated with increased intestinal permeability), infections. Disruption of the glycocalyx contributes to the formation of plaque (atherosclerosis).
  9. Modified LDL particles might also migrate through the junctions that connect adjacent endothelial cells either inside macrophages or on their own. Many factors, known and unknown likely determine the susceptibility or permeability of these junctions to this migration.

These are the major points, but there is allot more to discuss. Substituting “vegetable oils” for saturated fat in our diets not only increases the amount of oxidized LDL but also increases a dangerous lipoprotein called Lp(a). On third of Americans have an amount of Lp(a) that is considered “high risk” for heart attack and stroke. More about that in a future post.

Then there is the process of an actual heart attack or stroke which involves disruption of plaque and the creation of a blood clot that ultimately disrupts the flow of blood and the death of heart or brain tissue. The susceptibility of plaque to disruption is a huge topic that involves high blood pressure, diabetes, insulin resistance, oxidative stress, inadequate sleep, and stress to name a few. So much more to discuss.

But getting back to the title of this post, why don’t you ask your elected representatives why our tax dollars continue to subsidize nutritional root causes of death, disability and disease?

Here are some links to papers and books that support the discussion above.

Circulating Oxidized LDL Is a Useful Marker for Identifying Patients With Coronary Artery Disease

Cholesterol deposition in macrophages: foam cell formation mediated by cholesterol-enriched oxidized low density lipoprotein.

Erythrocyte fatty acid profiles can predict acute non-fatal myocard… – PubMed – NCBI

Changes in Dietary Fat Intake Alter Plasma Levels of Oxidized Low-Density Lipoprotein and Lipoprotein(a)

Low-density lipoprotein subclass patterns and risk of myocardial in… – PubMed – NCBI

Subendothelial Lipoprotein Retention as the Initiating Process in Atherosclerosis

Oxidative susceptibility of low density lipoprotein subfractions is… – PubMed – NCBI

Effects of linoleate-enriched and oleate-enriched diets in combinat… – PubMed – NCBI

Enhanced oxidative susceptibility and reduced antioxidant content o… – PubMed – NCBI

Susceptibility of small, dense, low-density lipoproteins to oxidati… – PubMed – NCBI

Modulation of Endothelial Glycocalyx Structure under Inflammatory Conditions

Oxidized Lipoproteins Degrade the Endothelial Surface Layer

S1P Control of Endothelial Integrity

Mechanical control of the endothelial barrier. – PubMed – NCBI

Therole of actin-binding proteins in the control of endothelial bar… – PubMed – NCBI

The Fats of Life, Dr. Glen Lawrence

Functions of plasmalogen lipids in health and disease

Grain Brain: The Surprising Truth about Wheat, Carbs, and Sugar–Your Brain’s Silent Killers: David Perlmutter, Kristin Loberg: 9780316234801: Amazon.com: Books

Finally a quote from the Dali Lama (thanks to my cousin Diane for bringing this to my attention).

“Man. Because he sacrifices his health in order to make money. Then he sacrifices money to recuperate his health. And then he is so anxious about the future that he does not enjoy the present, the result being that he does not live in the present or the future, he lives as if he is never going to die, and dies having never really lived.”

Eat clean, live clean, sleep well, exercise wisely, rest often, enjoy the company of loved ones, spend time outdoors and live in the present.

BOB

Chronic Pain Reduced by the Paleo Lifestyle

I spend 50% of my clinical time treating chronic pain patients. A paleolithic diet which consists of pastured grass-fed meat, free range poultry and eggs, fresh seafood, fresh vegetables, fruits and nuts decreases inflammation by eliminating major sources of dietary induced inflammation.

Yesterday I saw a patient one month after he started a paleolithic lifestyle (paleo diet, 8 hours of sleep per night- cycling with the sun, regular exercise including a prescribed spine rehab program).

Within 30 days his pain  has decreased by more than 50%, He feels  more energetic. He stated “I have started to dream again and get a full night’s sleep”. He has lost 12 pounds in one month and his blood pressure is down. He is ready to return to work after not working for eight months (with some activity restrictions). He is not taking any opiate pain medication.

His MRI scan and X-rays of the spine will not demonstrate any improvement. He still has degenerative disc disease, one or more tears in a disc annulus (outer wall of the disc) and arthritis in the facet joints of his neck (cervical spine) and lower back (lumbar spine). But the lifestyle elements that have contributed to his chronic inflammation have been significantly reduced in just 30 days and he has benefited “tremendously” in his own words.

There are many mechanisms involved with chronic inflammation. Most patients with chronic pain have an inflammatory component. Many patients with chronic pain are overweight or obese. Excess visceral adiposity (fat around the internal organs) creates a state of chronic inflammation by constantly producing inflammatory chemicals called chemokines and cytokines. These inflammatory mediators are produced by the fat cells and by the white blood cells (macrophages) that reside alongside the fat cells. They contribute to a process called central sensitization where the brain and spinal cord nerves that mediate pain  become sensitized and over-react to sensory input. Interleukin 6 is one of these mediators. Increased levels are associated with fatigue, depression and a state of hyperalgesia where painful stimuli are amplified. Tumor necrosis factor alpha is another important inflammatory mediator produced in excess when excess fat accumulates around the internal organs. Weight loss is essential to decease systemic inflammation, particularly in the setting of chronic pain when someone is overweight or obese.

Pro-inflammatory foods can also increase inflammation by altering intestinal flora and increasing intestinal permeability. These mechanisms have been discussed in previous posts and in the manifesto page of this website.

Few patients follow my dietary and lifestyle advice. Most seem to prefer taking pills, getting injections and other interventional pain procedures. In other words, they prefer to “be-fixed” rather than  take lifestyle initiatives that are likely to not only decrease their pain but also improve their general health. As an interventional pain practitioner I encourage patients to take full advantage of the pharmacology and interventional procedures that are likely to help. But without significant changes in bad dietary habits, poor sleep hygiene and without adopting a rehabilitation exercise program the pills and injections/procedures are much less effective and the prognosis is poor.

Stress reduction is also essential for health in general and for pain reduction in particular. Yet despite repeated recommendations to utilize an inexpensive stress reduction workbook, few patients ever bother to take this important step to reduce pain, anxiety and suffering.

Our culture is one in which patients expect to “be fixed” rather than to be led down a path which leads to healing and functional improvement by actively participating in their own rehabilitation and healing. Our culture is also one in which  major organizations provide bad dietary advice, particularly with respect to encouraging increased consumption of grains and legumes which have pro-inflammatory components and anti-nutrients. We evolved over a few million years without consuming grains, legumes, refined vegetable olis or dairy. Our evolutionary biology and physiology thrive when these foods, particularly processed foods are eliminated from the diet and we consume only those whole natural foods we have evolved to eat.

Modern medicine provides many remarkable drugs, surgeries and procedures that can be life saving and life altering. But application of this technology without addressing the fundamental determinants of health (proper nutrition, restorative sleep, judicious exercise, stress reduction, and restoration of circadian rhythm) yields much less benefit. Ultimately, unless we remove from our lives the destructive components of modern society and culture we cannot heal and instead continue to suffer from chronic degenerative diseases that cause pain, loss of intellect and loss of mobility.

No references tonight, just comments and reflection. References have been provided in previous posts.

Peace, health, and happiness.

Dr. Bob

The bacteria in your gut are essential to your health Part II, obesity, metabolic syndrome and dysbiosis

I have discussed the evidence linking the mix of bacteria in your gut (gut flora) to health and disease in Part I. The Bacteria in your Gut are essential to your health Part I | Practical Evolutionary Health

Today I will discuss the evidence related specifically to  obesity and metabolic syndrome (the constellation of obesity, insulin resistance, high blood pressure, and abnormal blood lipids). My discussion will follow closely the evidence and theory presented in research and review papers authored by Dr. Cani and colleagues. The first one is titled:

Gut microbiota controls adipose tissue expansion, gut barrier and glucose metabolism: novel insights into molecular targets and interventions using prebiotics.”

You can find the full text of this article here .

I have had the pleasure of corresponding with Dr. Cani by e-mail regarding her many publications investigating the relationship between gut flora, obesity, and metabolic syndrome.

“Recently, we and others have identified several mechanisms linking the gut microbiota with the development of obesity and associated disorders (e.g. insulin resistance, type 2 diabetes, hepatic steatosis).”

Explanation: The gut microbiota are the bacteria, viruses and other “bugs” that reside in our intestines. Insulin resistance can occur in various parts of the body, wherever insulin has an effect including fat cells, liver, muscle, brain. When higher amounts of insulin are required to achieve an effect this is called insulin resistance. In Type 2 diabetes, the pancreas is still able to make insulin but insulin is less effective in controlling blood sugar. In Type I diabetes the pancreas no longer produces insulin. Hepatic Steatosis means fatty liver disease. The liver accumulates fat and this can lead to cirrhosis, liver failure and death. Alcohol consumption can cause this but when alcohol is not involved this is called Non-Alcoholic-Fatty-Liver Disease (NAFLD). Our nation presently has an epidemic of not just obesity but also NAFLD. Evidence points to  excess carbohydrate consumption and excess consumption of vegetable oils (linoleic acid)  as contributing factors in NAFLD.  Carbohydrate restriction and consumption of saturated fat, particularly medium chain fats (as found in coconut) can protect against NAFLD. But the gut flora also play a role. The mechanisms involved are many.

“Among these, we described the concept of metabolic endotoxaemia (increase in plasma lipopolysaccharide levels) as one of the triggering factors leading to the development of metabolic inflammation and insulin resistance.”

Endotoxemia occurs when a toxin from certain kinds of bacteria circulates in the blood. This endotoxin enters our blood through our intestines under conditions in which the protective barrier of the intestines is compromised. The compromise of the intestinal barrier is variously referred to as ” leaky gut” or “increased intestinal permeability”. Wheat gluten-gliadin  causes increased intestinal permeability (especially in celiac disease) as can other plant lectins. In this discussion, the gut bacteria also contribute in the setting of “dysbiosis” (the beneficial effects of helpful bacteria are overwhelmed by the harm-causing bacteria when a healthy balance is not present)

Lipopolysaccharide (LPS) comes from the outer wall membrane of certain bacteria. Blood plasma is the liquid part of blood in which the blood cells circulate. So an “increase in plasma lipopolysaccharide” simply means that there is more LPS circulating in the blood. That is a bad thing. Depending on how much is circulating this alone can cause organ failure and death and is a major part of the physiologic changes involved in septic shock. But lower levels of LPS circulating in the blood can cause chronic low grade inflammation and insulin resistance. Obesity is associated with chronic inflammation and increased LPS circulating in the blood and being distributed to various organs where it wreaks havoc.

“Growing evidence suggests that gut microbes contribute to the onset of low-grade inflammation characterizing these metabolic disorders via mechanisms associated with gut barrier dysfunctions.”

“We have demonstrated that enteroendocrine cells (producing glucagon-like peptide-1, peptide YY and glucagon-like peptide-2) and the endocannabinoid system control gut permeability and metabolic endotoxaemia.”

That is a mouth-full. Over thirty different kinds of hormone producing cells have been found in the human intestine. These cells are called enteroendocrine cells. The hormones produced by these cells have many effects. You can find a great review of these cells and their effects here .

In Dr. Cani’s review article she describes how some of these hormones produced in the gut can increase intestinal permeability and allow more of the toxic, inflammation producing LPS to enter the bloodstream. But these hormonal effects are just part of the picture. Another part relates to endocannabinoids.

The  Endocannabinoid system in humans is complex and relates to hunger, satiety, energy metabolism, and yes gut permeability. Endocannabinoid refers to our internal (endo) production of cannabis like substances. Pot smoking people get the munchies because of the appetite stimulating effects of marijuana. But endocannabinoids have many other physiologic effects including the modulation of pain, mood, immune function and memory.

Dr. Cani describes in great detail the evidence supporting the roles that the gut flora play in influencing intestinal permeability mediated through the effects of various hormones and endocannabinoids. In animal and human studies changing the gut flora produces changes in these hormones and endocannabinoids which in turn can increase or decrease intestinal permeability and increase or decrease circulating LPS.

It turns out that specific  Prebiotics can produce growth of beneficial gut bacteria and through the series of steps outlined above, reduce inflammation in the body, improve blood sugar, improve insulin sensitivity, and decrease fat,

Oh, and similar to the endocannabinoid system, there is an “apelinergic system” in our bodies that also plays a role. If you want to read more about these systems you should read the original article and the other links below to related articles.

I have discussed in the past that fecal transplants have been used to treat the specific dysbiosis that occurs with C Difficile colitis. But fecal transplants have many potential beneficial uses.

The Fatlose 2 trial is presently studying the effects of fecal transplants on insulin resistance and related problems in human volunteers. I will let you know when the results are published, Studies conducted in rodents have demonstrated significant weight loss and improved insulin sensitivity when obese rodents receive fecal transplants from lean rodents.

In summary: dysbiosis represents an unhealthy mix of bacteria in the gut

  • dysbiosis causes increased intestinal permeability (leaky gut)
  • increased intestinal permeability leads to increased circulating LPS, which is bad
  • elevated levels of circulating LPS create a chronic state of inflammation which contributes to obesity and metabolic syndrome
  • the mechanisms that link dysbiosis to intestinal permeability include hormonal disruption (enteroendocrine cells) and the endocannabinoid system. Other mechanisms are also likely in play.
  • prebiotics and probiotics can mitigate dysbiosis, reduce intestinal permeability, reduce inflammation, and offer potential therapy for obesity and metabolic syndrome
  • fecal transplantation offers a potential for treatment for obesity and metabolic syndrome, research is underway

Our ancestors lived and evolved for a few million years prior to the relatively brief ten thousand years of agriculture and one hundred years of industrialization. The overuse of antibiotics in medicine and animal husbandry have contributed to dysbiosis. Other factors include stress, disruption of circadian rhythm, sleep deprivation. Cesarean delivery and avoidance of breast feeding conspire to dysbiosis. Processed foods feed unfriendly bacteria in our guts at the expense of beneficial bugs. Agricultural foods have introduced dietary lectins which also increase intestinal permeability and thereby contribute to chronic inflammation. The further we stray from our evolutionary niche, the more problems we experience.

This discussion just touches the surface of gut flora, dysbiosis, health and disease. We have yet to explore the gut-brain axis. Our gut and microflora communicate with and effect the function of our brain and other organs as well.

We will continue to explore health and disease from an evolutionary perspective.

Below are links to articles related to our discussion.

Peace, health and happiness.

BOB

Gut microbiota controls adipose tissue expans… [Benef Microbes. 2014] – PubMed – NCBI

Glucose metabolism: Focus on gut microbiota, … [Diabetes Metab. 2014] – PubMed – NCBI

Probiotics, prebiotics, and the host microb… [Ann N Y Acad Sci. 2013] – PubMed – NCBI

Crosstalk between the gut microbiota a… [Clin Microbiol Infect. 2012] – PubMed – NCBI

Gut microbiota and its possible relationship … [Mayo Clin Proc. 2008] – PubMed – NCBI

Enteroendocrine Cells: Neglected Players in Gastrointestinal Disorders?

Stomach bacteria can cause and worsen heart disease

A recent study from Italy (1) has identified a relationship between the bacteria that causes stomach ulcers and heart disease. H Pylori is a bacteria that can colonize the lining of the stomach and remain there for a lifetime unless diagnosed and eliminated with antibiotics. This bacteria was demonstrated to be a major cause of stomach ulcers by two physicians ( Dr. Barry Marshall and Dr. Robin Warren) who won the Nobel Prize for their finding.

Atherosclerosis the formation of plaque in the walls of arteries, is in large part an inflammatory process (2,3). The coronary arteries supply oxygenated blood to heart muscle and heart valves. A heart attack (myocardial infarction) occurs when a plaque  ruptures or tears, sending debris downstream in a coronary artery. That debris and/or the exposed ruptured plaque causes  a blood clot that obstructs blood flow to a portion of the heart and if the clot remains untreated a heart attack (muscle damage) occurs within minutes to hours. This process can also result in a fatal abnormal heart rhythm (ventricular fibrillation).

A major source of inflammation that is known to contribute to atherosclerosis and heart attacks is infection (2). Many patients suffer heart attacks following an acute infection or severe emotional stress.  Inflammation is involved in forming plaques, creating unstable plaques, causing plaque to tear or rupture and inflammation is involved in the dynamic process that leads to a heart attack (3). To quote the authors of this study:

Ischaemic heart disorders are the consequence of an atherosclerotic process. A concomitant cause of atherosclerosis is inflammation. Infections represent the single most frequent determinant of inflammation. In case of H pylori infection, the organism colonises the human stomach for life (if infection is not properly treated); therefore, the trigger is continuous and inflammation lasts for a lifetime.

The authors of this study found that a certain subset of H Pylori bacteria carry a protein that is similar to two or more very important and essential proteins in heart muscle. Those proteins are called human tropomyosin and cardiac ATPases. Both types of proteins are essential to the ability of the heart muscle to pump blood through the heart.

The authors postulate a mechanism called molecular mimicry. Because H Pylori proteins are very similar to certain proteins in the heart, colonization or infection in the GI tract by H Pylori results in an immune response directed against these foreign proteins which are very similar to proteins in heart muscle. The immune system”mistakes” these heart muscle proteins for the foreign proteins in H Pylori and mounts an immune response against the heart muscle. The study found that patients infected with certain H Pylori strains had higher circulating levels of inflammatory markers and BNP . BNP is associated with heart failure, (loss of heart muscle contracting ability) and loss of heart muscle function results in a poorer prognosis in patients with coronary artery disease.

Thus this study supports a direct link between bacterial infection in the GI tract and heart disease, mediated through the immune system.

This sort of molecular mimicry has been recognized in medicine as it relates to two very well known diseases caused by infections with a species of streptococcus (as in strep throat). Those diseases are rheumatic heart disease (also called rheumatic fever)  and glomerulonephritis, Either of these can occur as a complication of strep infections, ergo the importance of diagnosing and treating strep throat.

H Pylori represents one of many examples of the interplay between bacteria in our GI tract, the immune system and disease causation. Intestinal dysbiosis (imbalance between healthy and disease causing bacteria that reside in our gut) has been associated with a  multitude of disease processes including obesity, diabetes, psychiatric disorders and cancer (5,6,7,8,9,10).

An essential component of this process is the entry of foreign proteins or other antigens (immune stimulants) across the gut wall into the body where the immune system gets activated. Intestinal Permeability is a term that describes the ability of substances to cross the GI barrier (intestinal wall) and enter the circulation (blood or lymph glands). I have discussed this before. There are many potential causes of increased intestinal permeability (leaky gut) including small intestinal bacterial overgrowth (a specific kind of dysbiosis) dietary sources such plant lectins and saponins found in grains and legumes, stress, sleep deprivation and medications such as NSAIDS. When an individual suffers from leaky gut (increased intestinal permeability) the probability that toxic substances can enter the blood stream increases. Endotoxin (produced by pathogenic bacteria in the gut) has been related to many inflammatory disease processes wreaking havoc when it penetrates the intestinal barrier.

Intestinal permeability, auto-immune disease, molecular mimicry, and gut dysbiosis are topics often discussed in the Paleo community. These topics represent physiologic processes that relate to humans deviating from our evolutionary habits, diets and lifestyles.

References are below.

Peace.

BOB

(1)  Cross-sectional Study: CagA–positive Helicobacter pylori Infection, Acute Coronary Artery Disease and Systemic Levels of B-type Natriuretic Peptide Journal of Clinincal Pathology. 2014;67(3):251-257.

(2) 11. Epstein SE, Zhou YF, Zhu J. Infection and atherosclerosis: emerging mechanistic paradigms. Circulation 1999;100:e20–8.

(3)  Ross R. Atherosclerosis: an inflammatory disease. N Engl J Med 1999;340:115–26

(4)  Mayr M, Kiechl S, Mendall MA, et al. Increased risk of atherosclerosis is confined to CagA-positive Helicobacter pylori strains: prospective results from the Bruneck study. Stroke 2003;34:610–5.

(5) Diabetes, obesity and gut … [Best Pract Res Clin Gastroenterol. 2013] – PubMed – NCBI

(6) Involvement of gut microbiota in the de… [Gut Microbes. 2012 Jul-Aug] – PubMed – NCBI

(7) Crosstalk between the gut microbiota a… [Clin Microbiol Infect. 2012] – PubMed – NCBI

(8) [The role of gut microbiota in… [Postepy Hig Med Dosw (Online). 2013] – PubMed – NCBI

(9) [Research advances in th… [Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2013] – PubMed – NCBI

(10) The gut microbiota, obesity and insulin resi… [Mol Aspects Med. 2013] – PubMed – NCBI

Intestinal Permeability, Food and Disease

In medical school I learned some fundamental concepts about nutrition and digestion that turn out to be wrong. For example, we were taught that proteins in our diet are completely broken down into single amino acids in the gut, then absorbed through the wall of the intestine as individual amino acids. Turns out that not all proteins are completely digested in this manner and that fragments of proteins that are several amino acids long can be absorbed through the gut and enter our blood. Examples of such proteins include wheat gluten and bovine serum albumin (found in cows milk and whey protein) to name a few. The problem with absorbing such nutrients into our bloodstream is that these protein fragments are “foreign” and can be recognized by our immune systems as foreign, triggering an immune (inflammatory) response.

Some peptides (short chains of amino acids) in bovine serum albumin have structural similarity to peptides in human tissues. This foreign protein has been implicated in autoimmune diseases such as Multiple Sclerosis, Rheumatoid Arthritis and Type 1 Diabetes.

Other substances such as bacterial endotoxin similarly can be absorbed into the blood and cause trouble. Endotoxin, also called LPS or  Lipopolysaccharide, is a major component of the outer membranes of certain kinds of bacteria (gram negative bacteria such as E-coli) that live in the  Lumen of our gut. High levels of endotoxin circulating in the blood occur during septicemia and can result in death from septic shock. Lower levels of circulating endotoxin have been demonstrated to contribute to alcoholic and non-alcoholic liver disease, both of which can cause liver failure and death.

Intestinal wall permeability is governed by many factors. There are regulatory proteins that open and close the gaps (tight junctions) between the cells that line the walls of our intestines, thereby allowing more and larger foreign substances to enter our blood. This mode of entry is referred to as “paracellular” since it does not involve the usual absorption mechanism through the walls of the cells that line the intestines.

Substances regularly consumed by Americans known to increase intestinal permeability include gluten (the sticky protein found in wheat, barely, rye, oats), alcohol, non-steroidal anti-inflammatory drugs  like ibuprofen (Motrin, Advil), naprosyn (Alleve), and aspirin.  Refined “vegetable oils” that are high in a specific Polyunsaturated fatty acid called linoleic acid (examples of these vegetable oils include corn oil, soy oil, cottonseed oil) have also been demonstrated to increase intestinal permeability.

Vegetable oils have also been found to enhance the liver inflammation and destruction caused by  alcohol which is at least in part mediated by absorption of endotoxin and ultimately also caused by oxidative stress.

The same applies to non-alcoholic liver fatty liver disease. (Progression of alcoholic and non-al… [Drug Metab Pharmacokinet. 2011] – PubMed – NCBI)

Interestingly, consumption of saturated fat (as found in beef tallow, coconut oil, butter and cocoa butter-the oil of dark chocolate) protects the liver from inflammation and destruction caused by alcohol, while polyunsaturated fat consumption (vegetable oils)  do the opposite. (References above and below)

There is growing evidence for a link between auto-immune disease and Alterations in intestinal permeability. Increased intestinal permeability (IP) has been observed in a substantial percentage of individuals with Type I diabetes. It is commonly observed in populations at high risk of developing Crohn’s disease and has been observed in patients who subsequently develop Crohn’s disease. Patients with ankylosing spondylitis have increased IP and although these patients are typically treated with NSAIDs which increase IP, the effects of NSAIDS have been isolated from a primary defect in IP which is shared by relatives without the disease.

“increased intestinal permeability is observed in association with several autoimmune diseases. It is observed prior to disease and appears to be involved in disease pathogenesis.”

A paleolithic diet avoids all sources of gluten (paleo is grain-free) and it also avoids refined “vegetable oils”. These food items present a double hit relative to inflammation. First, they increase IP which increases circulating levels of various “foreign” proteins and other foreign macromolecules which can stimulate the immune system. The second hit from these food items represents their direct inflammatory effects once absorbed into the body. I have previously discussed the  inflammatory response to excess omega six fats here.

An excellent review of the importance of the ratio of omega six fats found in “vegetable oil”  to omega three fats found in fish oil can also be found here ,  here   and  here.

The potential inflammatory response and anti-nutrient effects of cereal grains and in particular the gliadin portion of wheat gluten has been discussed and reviewed in multiple papers including:

Do dietary lectins cause disease?

Non-Celiac Gluten Sensitivity: The New Frontier of Gluten Related Disorders

BMC Medicine | Full text | Spectrum of gluten-related disorders: consensus on new nomenclature and classification

BMC Medicine | Abstract | Divergence of gut permeability and mucosal immune gene expression in two gluten-associated conditions: celiac disease and gluten sensitivity

Bioactive antinutritional peptides derived from cere… [Nahrung. 1999] – PubMed – NCBI

Antinutritive effects of wheat-germ agglutinin and… [Br J Nutr. 1993] – PubMed – NCBI

This discussion just scratches the surface of the effects of intestinal permeability and health. Future discussion will address how the micro-flora (bacteria and viruses that live in our GI system) affect intestinal permeability, our brains, our immune system and our health.

Avoiding foods that we have not evolved to eat will result in decreased inflammation and will often reduce the symptoms of auto-immune and other inflammatory diseases. Many present day diseases are considered by evolutionary biologists to represent a mismatch between our culture, food, and our evolutionary biochemistry. These diseases were likely rare or non-existent  before the advent of agriculture and the subsequent industrialization of society with highly processed foods.

Eat only pastured meat, free range poultry and eggs, wild seafood, fresh vegetables, fruit and nuts and you will avoid the problems discussed above as well as a host of other problems to be discussed in future posts.

Peace,

Bob Hansen MD