SIBO: Symptoms of IBS or Small Intestinal Bacterial Overgrowth

Ever wondered what is inside your intestines? Well, you are about to cringe.

The human intestines are like a continuous pipe which runs from the stomach to the anus. This pipe takes in the food that you eat into your blood so that it is distributed to all other parts. To add to that, this pipe has some small inhabitants, not visible to the eye but can cause good and evil in equal measure; these are the gut microbomes. Good bacteria help in digesting food while the bad bacteria make you sick. When the balance between good and evil is lost, then a visit to the ER becomes inevitable and your doctor might mention SIBO.

What is SIBO?

Small Intestinal Bacterial overgrowth (SIBO) is a disorder that involves an increase in the number of both good and bad bacteria present in the small intestines. The bacteria are normally there but when they overgrow, they cause problems. More like when they are too many and now trespass into areas they are not allowed to.

¹The large intestines, on the other side, contain a large number of both safe and unsafe microbes; they are not as fragile as the small intestines and can handle a few notorious ones.

The small intestine is fragile and the body, therefore, has defense mechanisms that keep the environment of the small intestine clear of any ill-meaning bacteria. A breach in this defense mechanism may lead to an overgrowth which will manifest as SIBO.

How does SIBO come about?

As earlier mentioned, the human intestines contain a colony of bacteria that is constantly under watch to remain in certain levels. Disturbances in the number or type of bacteria in the intestines may manifest as SIBO. To keep the numbers in check, the body has a well-equipped tool box that helps fix any problem that may arise. ¹⁵These tools include; gastric acid, intestinal motility, intact ileocecal valve, antibodies in intestinal secretions, ¹⁴protective property of pancreatic secretions, and bile juice.  These tools have quite the names, don’t they? Let me break it down for you.

1. Gastric acid.

The stomach secretes a very strong acid, the gastric acid. It aids in digestion but also creates a very hostile acidic environment for harmful bacteria to grow and flourish.

1. Intestinal motility

The small intestines move to mix and churn food in the process of digestion. Remember the intestines are like a pipe and they wiggle around so that they can take in as much as food as possible; a little dance to appease the food to come in. This dance however, is annoying to the harmful bacteria and it keeps them at bay.

• Intact ileocecal valve.

This valve is like a gate that controls what moves from the small intestines to the large intestines. Like an actual gate, only that which has a permit can cross over from either the small or large intestines.

1. Antibodies

Antibodies are the soldiers of the body. If any suspicious-looking microbes are found, it is immediately destroyed and this helps to keep everything in order.

If any of these four main tools are compromised, the body becomes more vulnerable to an overgrowth of bacteria. The bacteria are likely to take advantage of the breach in security and establish their colonies excessively.

What are the symptoms of SIBO?

⁵SIBO often manifest as problems of digestion since it involves the intestines

The most common symptoms include; abdominal bloating, diarrhea, abdominal discomfort, weight loss, malnutrition.

These symptoms, however, do not pinpoint to SIBO since they are common in other problems related to the digestive tract. Therefore, the doctors have to run tests to confirm that it is actually SIBO.

 SIBO and IBS

^8,9Irritable Bowel Syndrome (IBS) is another disorder of the digestive tract that has been linked to SIBO. The exact relation is unclear, but inflammation plays a key role.

‘What is inflammation?’ you ask. This is a protective mechanism of the body in response to injury or irritation. ⁷The excess bacteria in SIBO irritate the lining of the small intestines. This lining is made of mucus which coats the delicate inner side of the intestines. As a counter reaction, the body sends its soldiers- the antibodies and a war ensues. In the process, the lining gets damaged. This damage involves destroying the mucus coat, leaving the intestines exposed and easily irritable thus increased risk of irritable bowel syndrome.

Does SIBO cause nutritional deficiency?

Ooh yes!

As we have already discussed, ¹⁵the excess bacteria that are the hallmark of SIBO, cause eventual damage to the lining of the small intestines. The small intestines are mainly responsible of taking in food and the nutrients in them. When they are damage, they are unable to perform this task and this translates to nutritional deficiency

¹³Some of the excess bacteria compete with the body to absorb some nutrients such as vitamin B12, just imagine!

¹⁴In addition to that, the excess bacteria also interfere with the absorption of some other vitamins; vitamins A, D, E, and K. A deficiency in these enzymes will cost you a little more that you would ever bargain for. For example, a deficiency in vitamin A can cause night blindness; liver problems and acne just to mention a few.

Diagnosis

¹⁷For the doctor to confirm the presence of SIBO, they mainly rely on eliminating other possible problems. This is because SIBO presents with general symptoms that can also be present in other diseases.¹¹Nevertheless, some tests have been developed to help look for SIBO. The most common test is a breath test. This test involves your doctor giving you glucose or sucrose orally. They will then test the gas that you exhale.

Here is the science behind it. The glucose and sucrose are given as bait to the bacteria. If there are excess bacteria, they will gulp down this meal and then produce some gas when they are full. The doctor then measures this gas and detects those bad boys.

Treatment

The treatment of SIBO aims at; treating the underlying cause, ¹⁵providing nutritional support, and treating the overgrowth. ¹⁰Nutritional support is given to correct and avert the deficiencies that may develop. Vitamin supplements are given for vitamins A, D, E, and K, and vitamin B12.

⁹The bacterial overgrowth is treated by may be treated with medication which either kill or reduce the dividing rate of the bacteria to decrease the overload.

What is important to remember is that SIBO does not happen overnight and just getting rid of the excess bad bacteris does not prevent re colonization.

For proper health and life without SIBO, it is important to support the person’s physiology to ensure that  there is adequate good bacteria coming in, appropriate nutrition that encourages and supports the good microbes, good digestion, a healthy balance of the gut brain axis and immune system.

References

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