Tag Archives: gut permeability

The Gut-Brain Connection

Screen Shot 2013-07-16 at 2.42.44 PMA large body of evidence is accumulating to support a role between healthy gut function, brain development and function of the central nervous system. The organisms contained in the gut should be considered an inner organ with functions similar in importance to any other organ present in the body. Disruptions in this “organ” may alter many things including brain function and cause symptoms like depression, anxiety, ‘brain fog’ and more.

At birth the human gastrointestinal tract is sterile, however, it is quickly colonized and by the age of one year, the bacterial profile looks similar to that of an adult.1 The connection between the gut and the brain is known to be bidirectional. This means messages from the gut affect brain function just as much as messages from the brain affect gut function.2

 The mechanism by which alterations in bacterial profiles of the gut affect how we feel, think and move is fascinating. It all begins with lipopolysaccharides (LPS). LPS are structures located on the surfaces of bacteria present in our gut. These LPS may actually get out of the gut and into the blood stream producing a very strong immune response. Normally, the gut does a very good job keeping these LPS from getting into the blood stream.3 However, when the barrier in the gut weakens (‘leaky gut’) LPS is more easily absorbed and enters circulation.  When this occurs, inflammation ensues. If the process continues, high levels of inflammation are generated and this begins to alter neurotransmitter levels in the brain. With enough change in neurotransmitter levels, mood, behavior and cognitive function suffer.

What causes leaky gut? There are a lot of factors, however, evidence points to a high fructose diet (sugary beverages), the Western diet (high in processed foods) and nutrient deficiencies like vitamin D, A, zinc and magnesium.These factors are also known to increase the ability of LPS to get into the blood stream.4

 Symptoms of depression, anxiety, ‘brain fog,’ or poor memory may not always be coming from your brain. The genesis of the problem might actually be in your gut! By maintaining a healthy diet and addressing potential nutrient deficiencies you may see many of your symptoms disappear without the need for expensive, mind-altering medications!

1Palmer C, Bik EM, DiGiulio DB, Relman DA, Brown PO. Development of the human infant intestinal microbiota. PLoS Biol. 2007 Jul;5(7):e177.

2O’Mahony SM, Hyland NP, Dinan TG, Cryan JF. Maternal separation as a model of brain-gut axis dysfunction. Psychopharmacology (Berl). 2011 Mar;214(1):71-88.

3Bested AC, Logan AC, Selhub EM. Intestinal microbiota, probiotics and mental health: from Metchnikoff to modern advances: Part II – contemporary contextual research. Gut Pathog. 2013 Mar 14;5(1):3.

4Teixeira TF, Collado MC, Ferreira CL, Bressan J, Peluzio Mdo C. Potential mechanisms for the emerging link between obesity and increased intestinal permeability. Nutr Res. 2012 Sep;32(9):637-47.

Advertisements

Leave a comment

Filed under Public Health

Quick! Get that kid some bacteria!

I recently came across an article that got my interest for a couple of reasons.  The article was about allergies and how many health practitioners are reporting an increase in the number of children they are seeing with allergies.  I agree.  In my office I see several children whose parent’s only complaint is their child’s allergies.  The second reason for my interest was one of the proposed reasons for this – an unhealthy balance of bacteria in the gut.

The number of kids with food allergies went up 18 percent from 1997 to 2007, according to the U.S. Centers for Disease Control and Prevention. About 3 million children younger than 18 had a food or digestive allergy in 2007, the CDC said.  These numbers are high and seem to be rising rapidly in rich, industrialized countries like the U.S. and Britain.  In fact, a recent study in the Journal of Allergy and Clinical Immunology found that visits to the emergency room at Children’s Hospital Boston for allergic reactions more than doubled from 2001 to 2006.

In my practice I have always contended that the Western diet and lifestyle plays a major role in the development of allergies in our children.  Now a small Italian study seems to confirm what I have postulated.

My theory has always been that the combination of being overly clean and eating diets high in refined carbohydrates and other allergenic foods has caused a massive immune imbalance.  This imbalance leads to over activation of the entire immune system resulting in reactions that range from minor annoyances to life threatening.

A study in Proceedings of the National Academy of Sciences compared the gut bacteria from 15 children in Florence, Italy, with gut bacteria in 14 children in a rural African village in Burkina Faso. They found that the variety of flora in these two groups was substantially different.

The children in the African village live in a community that produces its own food. The study authors say this is closer to how humans ate 10,000 years ago. Their diet is mostly vegetarian. By contrast, the local diet of European children contains more sugar, animal fat and calorie-dense foods. The study authors posit that these factors result in less biodiversity in the organisms found inside the gut of European children.

Now, in my opinion, it has very little to do with the fact that this African culture eats very little meat and simply with the fact that they consume a more natural, raw diet.  This leads to a more favorable balance of bacteria in the gut because of exposure.

Why are these bacteria important?

The bacteria in our gut work symbiotically with our systems in order to help us survive.  It is a true symbiotic relationship in that neither one of us (the bacteria or the person) would survive without the other.  They are important because they help digest certain proteins, help up absorb certain vitamins and minerals and perhaps most importantly with regards to allergies, maintains gut wall integrity or permeability.

Gut wall integrity is crucially important in not only preventing allergies but maintaining the health of the entire immune system.  So what happens when the balance of good bacteria changes in the gut?  Good question.

As the balance begins to be altered, the permeability of the gut begins to increase. Our digestive systems are designed to absorb a lot of things, but these things must be fully digested and of the appropriate size to be absorbed.  When our system becomes overly permeable, proteins that are undigested or are partially digested may get absorbed into our blood stream.  This is problematic.

Proteins are simply chains of amino acids linked together.  A small chain of amino acids is called a peptide.  A larger chain of amino acids or several peptides linked together is called a protein.  When we consume a hamburger, for example, the proteins are large and may be thousands of amino acids long.  It is the job of our intestinal tract to break down each and every one of those proteins into its individual components or amino acids.  If this does not happen, then peptides are what remain.  This is not problematic unless you have high gut permeability or a leaky gut. This leaky gut, from abnormal bacterial balance, now absorbs these peptides into the blood stream.

Why are these peptides a problem?  Because your body doesn’t recognize them as useful.  Your body recognizes amino acids as helpful.  Amino acids are often referred to as building blocks because they are used for so many things in the body.  That is precisely the reason the digestive system is designed to break down proteins into these components.  Peptides are not recognized and therefore the body sees them as foreign invaders and generates an immune response, or allergy, to them.  For some people this response is minor (itchy eyes, runny nose, hives, etc.) and for others it is life threatening (anaphylaxis).

Gluten, the protein from wheat, rye, oats and barley and casein, the protein from milk are notorious for being broken down incompletely in the gut and causing allergic reactions.  They are the most common simply because they are two of the most commonly consumed foods in the world (wheat and milk products).

What can I do to help myself or my child?

There are many things you can do.  First and foremost eliminate any food that you know causes you an issue. Secondly, you may consider having an allergy test.  This is important because many people are allergic to things they aren’t aware of.  An allergy test should also include food sensitivities. These are reactions to foods that don’t necessarily generate a full immune response in your body but do initiate a response on a lower level.  These are important to know because reducing your total allergic load is critical for helping you overcome your major allergies.

Also, take a digestive enzyme that is high in protease.  A protease in an enzyme that breakdown protein.  If you take this with a meal it will help insure that all proteins are properly digested.

Last, but certainly not least, take a probiotic.  A probiotic will help restore the healthy balance of bacteria in your gut and help you maintain the integrity of you gut wall.  This will insure that the permeability is appropriate and you are not absorbing micronutrients that your immune system views as dangerous.

Leave a comment

Filed under Diet, Public Health