Stress and Small Intestinal Bacterial Overgrowth (SIBO) – Thyroid & Gut Health


Updated: December 2021

The term for overall stress or stressors that one may experience is called the Allostatic Load. Excessive allostatic load is a major contributor to disease and illness. If you deal with chronic stress it can be a challenge to become truly well, healthy and happy.

Gaining “health” can be a real challenge for all of us because we are all under many different stressors as we go through our lives. These stressors can effect entire organ systems including the gastrointestinal tract and make us more prone to developing health problems such as Small Intestinal Bacterial Overgrowth (SIBO).

Stress can come at us from many different directions. It can be from environmental stressors, significant life events, or even trauma and/or abuse, and experiences in life.

The real trick here is to do everything you can to develop a balanced lifestyle which limits stress to a degree. Many people would say, “Good luck with that!” However, there are things that you can do to at least move yourself in the right direction.

We all know that exercise is important. Some of us stress over not getting enough exercise. Where others can stress over how much exercise to do each week.

Now we have tracking apps and watches to track how much we exercise. Oh, and don’t forget: you can now link in with everyone that you know and see how much they exercise and compare your numbers with theirs. That shouldn’t create any additional stress at all should it?

So, your level of exercise, diet, alcohol intake, cigarette smoking (including 2nd hand or 3rd hand smoke). Yes, there is such a thing as 3rd hand smoke. 3rd hand smoke is when the smoke interacts with the chemicals in other items such as your couch, paint in the walls, etc…

Just as 2nd hand smoke can be worse than 1st hand, 3rd hand smoke can be very damaging due the chemical reactions that it can cause.

What about the stress response that you may encounter when inhaling smoke from a nearby smoker when you are not a smoker? The same can happen with perfumes or other aromas, scents and fragrances.

Limbic System Activation

Ever notice that a certain smell can take you back to a certain point in time (maybe even decades ago)? Pleasant aromas can take you back to some good memories and have a calming effect on your nervous system.

I can remember being in the grocery store with my Mom and going down the coffee isle. Yes, I’m dating myself because I remember that they used to have open containers where you could get your own coffee beans. You would fill your bag and the smell was great.

It’s much different today because everything is sealed tight. I miss the coffee isle!

Why is the Limbic System Important?

Both pleasant and noxious odors (smells that aggravate your nervous system) can cause a very primitive response that stimulates a part of the brain called the limbic system.

Limbic stimulation is what happens when a pregnant woman smells something and it makes her vomit. It is the same neurological stimulation of the limbic system that makes you happy when you smell chocolate chip cookies cooking in the oven.

The limbic system can also be the source of an instant headache with certain perfumes or 2nd hand smoke from across the parking lot.

Interestingly, the limbic system is also the pleasure center that gets activated during sexual intercourse. It is the part of the brain that perceives sexual satisfaction.  Read my article Stress vs. Sex.

The limbic system controls, hunger, thirst, anger and aggression, and response to pain!!! I’ve talked a lot about the Sympathetic Autonomic Nervous System (SANS) in other articles and its effects on digestion. But, the SANS also regulates other functions such as blood pressure and breathing along with many other aspects of health.

By now, it should be really easy to see how something as simple as a stressor that involves anything from simple smells, exercise and even sex could drastically effect your overall allostatic load or stress levels.

Environmental stressors such as pollution, toxins, and chemicals from the plastic in water bottles/plastic dishes (Bisphenol A aka: BPA), stress at work, a bad or difficult neighbor, and home life can also play a major role in digestion and health.

Significant life events also play a major role in overall health and allostatic load. A death in the family can have devastating and lasting consequences for the entire family.

Financial concerns such as a bankruptcy or a foreclosure can agitate your entire nervous system. Remember, you have a neuro-endocrine-immune loop. When one system is affected, all are affected.

SANS vs. PANS Activation

What happens when you get pulled over for a speeding ticket? Your SANS kicks in and your heart races. Your hands might even shake.

When your SANS is activated, your Parasympathetic Autonomic Nervous System (PANS) is pushed down and suppressed, and guess what? Your PANS is what controls digestion. The SANS gets activated by “stressors” and inhibits digestion.

So, chronic stress or a high allostatic load will decrease your healthy and normal digestive processes. I realize that this is a lot of information with some difficult to understand concepts. However, a basic understanding of human physiology and nervous system function is important so that you can truly grasp why things in your body may or may not be working properly.

Enzymes throughout the body are very sensitive to stress. One area where this can be really important are your zinc stores. Zinc is the 2nd most common metal in the body. Iron is the most abundant but zinc is a close second.

Low Ferritin and Anemia

I see low iron and ferritin in patients on a frequent basis. We all know the potentially devastating effects of low iron when it comes to anemia and the corresponding low oxygen levels and hypo-perfusion of oxygen throughout the body (including the brain).

Low iron or anemia can cause many health problems but what most will notice is the overwhelming fatigue and brain fog. Low to no energy is one of the most common signs of anemia.

What about Zinc?

So, where does zinc come in? I used the phrase, “Zinc to Think” very often when I explain some of the critical functions of zinc to my patients. There are actual zinc receptors in the brain! A zinc deficiency can be a contributing factor to poor memory and even contribute to brain fog. A few of the functions of zinc include:

  • Zinc helps with the sense of smell and taste.
  • Zinc aids in immune system function.
  • Zinc helps your cells grow, multiply, and divide.
  • Zinc is involved with digestion and also helps with wound healing.

Good zinc levels are also necessary for the production of testosterone. Testosterone is mainly considered a male hormone. However, women have testosterone as well.

In fact, testosterone is a key hormone that affects sex drive in men and women. Low testosterone levels can cause a low libido (desire for sex).

The answer isn’t always taking hormones. Often, establishing and maintaining healthy zinc levels can do wonders in this area. One of the first items I test for in my new patients is zinc.

Zinc is also necessary for many enzymatic reactions. Enzymes are the movers and shakers inside of the body. They create and facilitate chemical reactions.

Enzymes convert proteins, make hormones, help with digestion… The list goes on and on. The bottom line is that zinc is necessary for helping the enzymes do their job. Low zinc levels can keep your enzymes from working properly.

I realize that at this point, you are probably thinking to yourself, “Okay, I get. It. But, how could zinc be tied in with digestion?” So, here you go: zinc is very sensitive to stress.

In my article Stress vs. Sex, I discussed how stress can cause cortisol production and a preferential pathway away from producing sex hormones and causing a low libido.

Stress levels can also cause a depletion of zinc. Zinc is water soluble. If you deal with a lot of stress, you could very well be urinating out your zinc stores and have a depletion. Remember, zinc is needed by many enzymes. And, a zinc deficiency can cause your immune system to be weakened.

Chronic Infections and Stress

A source of stress for the body can be a chronic infection. Many people don’t realize that the human body is a host for microorganisms.

In fact, the human body is a carrier for bacteria, viruses, fungi, and parasites. Low zinc levels can make you more susceptible to getting an infection.

A common bacterial infection is called small intestinal bacterial overgrowth (SIBO). So, what is SIBO? SIBO is an overgrowth of bacteria in the small intestine.

A common cause of SIBO is chronic and repeated exposures to antibiotics. There is always a cause and effect. Antibiotics can deplete bacteria (good and bad) from your small intestine and cause a migration of harmful and pathological bacteria from the colon or “large intestine” into the small intestine.

Your brain recognizes incoming stressors as Discerned Stress. An example of discerned stress when you see a large dog walking towards you and your children. People who worry a lot have a high level of discerned stress.

Another example of stress could be when people have a sense of helplessness when dealing with circumstances and the situation of having a sick family member.

I recently had a patient whose mother was admitted to a nursing facility because she had a serious health condition and her Drs. didn’t know the cause.

My patient was stressed to the max because she was having to fill out paperwork for the facility, insurance, etc… She was exhausted. She was upset because her mother was gravely ill and she couldn’t just go into the facility and visit with her Mom because the second she walked in the door, people were coming to her and asking for forms to be signed, etc…

When someone is under such a high level of stress, it doesn’t just affect the nervous system. It affects the entire body. From top to bottom.

Stress can lead to gastrointestinal hyperpermeability (leaky gut syndrome) and digestive problems. Your immune system can be altered and you could develop a migration of colon (large intestine) bacteria into your small intestine.

Antibiotics are proving to be less and less effective over time. Sometimes it’s because of the antibiotic resistant bacteria. It can also be from biofilm cloaking of bacteria so that the immune system can’t see the bacteria as foreign to the body. This can be a cause of chronic infection.

Infections are at the source of what I look to identify with my new patients. Cancer can cause death for certain. However, cancers usually have been in their developmental stages for years before they become life threatening. That is why early detection can mean the difference between life and death.

Infections Can Kill Fast!

An infection can kill you within 3 days! Many of my patients don’t have an acute infection that is immediately life threatening in the next 3 days, but most have a chronic, low grade infection that can cause inflammation inside of the body and lead to a host of symptoms including fatigue, brain fog, digestive dysfunction, joint pain, dermatological (skin) reactions, autoimmune diseases, thyroid problems, etc…

Remember, inflammation causes all disease. It is a destroyer of tissues in the body.

I’ve talked about it in numerous other papers and articles, but stress will always create a response inside of the body. Responses include neurological, hormonal and immune system changes.

Genetics and Stress

How someone handles stress can be affected by genetics, and life experiences. I live in Arkansas. Arkansas is well known for its tornado season.

I’m not afraid of tornadoes at all. I believe that when it is my time, it’s my time. Weather it’s a tornado or a car accident.

Did you see what I did there? Weather. I know, whether. But seriously, some people in Arkansas are terrified of tornadoes.

The stress that people can impose on themselves by watching the weather stations on t.v. non-stop is unbelievable. Most don’t realize it.

Obsessing over situations or circumstances can cause zinc depletion, negative limbic system responses, Sympathetic Autonomic Nervous System activation, and a weakened immune system.

The combination of these events can ultimately lead to migration of excessive amounts of harmful large intestinal bacteria into the small intestine and contribute to SIBO.

I enjoy using herbal formulas to help my patients get as healthy as possible while at the same time educating them on tools to control stressors that can lead to poor health.

If you create fertile soil and the proper environment, things will grow. Sometimes, it’s things that you don’t want.

Stress can create fertile soil and lead to growth of organisms that don’t belong (in areas that they don’t belong in). It is important to identify forms of stress and work to extinguish as many fires as possible so that you get a decrease in overall “allostatic load” and can therefore be healthier and happier.

Health is Happiness,

Dr. Keith Currie

What patients think:

I’m getting healed each and every day since I met Dr. Currie. I followed Dr. Currie’s recommendations and I lost 16 pounds so far. I’m still in the process of being healed, but every day I’m getting better. That’s why I keep working with Dr. Currie. My husband and I both knew that this was the answer. I’ve gone to doctors all over the United States and this is where my help is coming from. This is such a blessing.

by - Betty H.

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