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Fix your gut, fix your health


What we eat can affect the way we feel, think, and behave. Indeed, the gastrointestinal tract has often been called the “second brain”. You’ve probably heard the phrase “gut feeling”. Actually, we don’t often feel our guts, until it’s too late. Here’s how to identify common GI disorders, and what to do about them.

Nobel prize winner and microbiologist Elie Metchnikoff once said, “Death begins in the colon.”

Based on his years of research in the early 1900s he concluded that disease and aging are mostly due to toxic bacteria in the gut.

While that idea may seem a bit farfetched, when you have an understanding of the havoc that a dysfunctional gastrointestinal system has on the body, his theories suddenly become far more plausible.

The GI system 101

A properly functioning gastrointestinal system is critical for overall health and well-being, yet it is often treated as the red-headed stepchild of the body – underappreciated, ill-treated and otherwise ignored unless it starts making a lot of commotion.

Consider the following about the gastrointestinal system:

  • The gastrointestinal system comprises 75% of the body’s immune system.
  • There are more neurons in the small intestine than in the entire spinal cord.
  • It is the only system in the body that has its own, independently operating nervous system, called the enteric nervous system.
  • If you stretched out the gastrointestinal system in its entirety, it would have the surface area of a regulation sized singles tennis court.
  • There are over 400 species of microbes living in your gut, totaling over 15 pounds of mass and containing more bacteria than there are known stars in the sky.

Suffice it to say, if the body allocates this many resources to one particular system, it must be important.

In fact, we should start treating our gut with care if we are interested in weight loss, muscle gain or overall health in general.

A gut feeling

Actually, we don’t really feel our guts. Specifically, we don’t often feel gut pain or any other sensations. That’s because our guts lack pain sensing receptors (known as nociceptors).

Nocioceptors sense noxious stimuli and send signals to our brain to let it know. These signals are registered as “pain.”

For example, the next time you accidentally step on a nail or sharp object, thank your nociceptors. They’re responsible for forcing you to remove your foot to prevent further damage.

However, as indicated above, our gastrointestinal systems do not have this sort of pain sensing system. As a result, we typically don’t know when our gastrointestinal systems have a problem. Instead we have to wait until things get bad enough to present symptoms to us.

If you have any symptoms such as…

  • gas
  • bloating
  • burping after meals
  • inadequate digestion (feeling like you have a brick in your stomach after you eat)
  • undigested food in your stools
  • foul smelling stools
  • constipation
  • diarrhea
  • burning in the stomach
  • bad breath
  • nausea

…you can be sure you have some type of gastrointestinal dysfunction.

Yet, oddly enough, many other symptoms typically aren’t experienced in our GI systems. Often, things like hormonal imbalances, migraines, allergies, eczema, and autoimmune disease all can be traced back to GI system problems. Interesting, isn’t it?

But, as indicated, there are a host of other symptoms that can be traced back to gut problems. We’ll discuss those in a minute.

Guts gone wild

Because there are so many systems that can be negatively affected by a dysfunctional gastrointestinal system, I’ve created a short video to demonstrate how just how all-encompassing the gastrointestinal system is, and which systems can be involved.

Check it out:

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What to do

From this video you can see that almost everything — from a compromised immune system, to a problematic stress hormone situation, to an altered sex hormone system, to blood sugar irregularities — can be related to gut problems. These problems can even feed back to cause more gut problems.

One of the best ways to stop a vicious GI-related cycle is to control inflammation and identify food sensitivities. In my clinic, we do this with a strict elimination diet for a period of 3-6 weeks.

A good elimination diet means removing foods to which many people are sensitive, including:

  • wheat and gluten containing foods
  • soy
  • all dairy products
  • corn
  • citrus
  • the nightshade family of vegetables (i.e. onions, tomatoes, eggplant)
  • pork
  • eggs
  • anything else we think may be causing you issues

You may be asking, “What’s left to eat?” Good question. You’ll eat a lot of rice, turkey, fish, lamb, green vegetables, and certain fruits (i.e. blueberries, apples).

This may seem restrictive but I assure you, the people who actually have the persistence to embark on such a program will be glad they did. The effects of a properly followed elimination diet are sometimes nothing short of miraculous.

Finally, as a general rule, the more strict you can be, the better. I often encourage people not to undertake such a diet without supervision. It’s just too demanding and requires too much specialized knowledge.


Once people have followed three weeks of a strict elimination plan, we then begin reintroducing foods to see which ones cause problems.

To reintroduce a food, we continue following the elimination diet, but add in one food we eliminated. We keep it in the diet for two days and see what happens.

For example, after 3 weeks, we might try reintroducing eggs. We might eat eggs a couple times a day for two days.

We pay careful attention to any symptoms experienced, such as joint pain, headaches, sinus issues, foggy thinking, fatigue, nausea, skin issues, and/or poor sleep. Almost anything can resurface that otherwise disappeared during the previous three weeks.

If there are any “positive” reactions to a food — meaning certain symptoms reappeared — that means the food is a problem and must be avoided for a period of at least 6 months.

I know this process seems simple. But don’t negate it just because it’s simple. In my clinic, I’ve seen profound effects. While there are a number of food sensitivity tests available, the gold standard in immunology is a good, old-fashioned elimination diet.

If you have a reaction

If you have a reaction to certain foods, avoid them.

However, you might not have to avoid them for life. It may be that your gastrointestinal system is inflamed, making you sensitive to foods you might otherwise not be. But wait for at least for 6 months before trying them again.

In the meantime, you might consult with a doctor that understands gastrointestinal function and can give you gut-repairing nutrients such as glutamine, marshmallow root, gamma oraznol, slippery elm, etc.

Another option is to find a doctor that runs the “GI Effects Test” through a lab called MetaMetrix. It is the best test of gastrointestinal function that I currently know of, and can help identify a multitude of gut issues, including infections that most people do not realize they have.


The gastrointestinal system is one of the most underappreciated systems in the body. It has a profound impact on our health, function, and well-being — all of which affect our ability to achieve our physique goals.

During the course of our lifetimes, many of us will suffer from poor GI function. Be prepared for this and have a plan in place for when it happens.

“The gut is always right.”
—Sharon Osbourne (Ozzy’s wife)

About the author

Dr. Bryan P. Walsh is a Naturopathic Physician specializing in nutritional biochemistry, functional laboratory testing and natural medicine. He is a guest lecturer at the University of Maryland School of Medicine, has been a presenter at national conferences, and is currently an advisor to the Precision Nutrition team. For more, click here.

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