The small intestine bacterial overgrowth is often abbreviated to SIBO.
If the small intestine is colonized incorrectly, an unnatural number of lactic acid bacteria (lactobacteria) have settled in the small intestine. Lactic acid bacteria normally live in the large intestine, where they are wanted and usually do not cause any problems.
In the small intestine, these bacteria now ferment carbohydrates (sugar, starch) with the formation of gas, which explains the main symptoms (bloating, abdominal pain). This can also produce what is known as D-lactic acid. In contrast to L-lactic acid, which is also formed by the organism itself during natural metabolic processes, D-lactic acid is difficult for the body to break down again. It, therefore, remains in the intestine for too long, can get into the blood via the intestinal mucosa and acidify it. A so-called lactic acidosis has developed – acidification due to lactic acid. This in turn can lead to the concentration problems described below and to a kind of short-term mental confusion.
In addition, the bacteria that are mistakenly resident in the small intestine prevent the digestive enzymes from doing their job, so that the food cannot be digested properly. More incompletely digested food particles than usual reach the large intestine, which can now also lead to problems there, namely increased bacterial activity and thus bloating.
The typical symptoms of small intestinal overgrowth (SIBO) are a bloated abdomen and abdominal pain. Bloating often doesn’t go away, which explains the bloated stomach and pain. Most often, these complaints appear immediately after meals and persist for hours, which greatly affects the quality of life. Chronic diarrhea or chronic constipation can also set in which basically describes the symptoms of irritable bowel syndrome.
And indeed: Many irritable bowel syndrome patients do not suffer from their symptoms without a reason (as many doctors, unfortunately, tell these patients again and again), but as a result of an abnormal colonization of the small intestine. Yes, it is said to be over 50 percent of all IBS patients whose IBS is actually SIBO. You can more information on IBS in our article on IBS.
In addition, in the case of miscolonization in the small intestine (and thus also in the case of irritable bowel syndrome), concentration disorders and confusion can (but do not have to!) occur, a kind of drowsiness. These symptoms are attributed to D-lactic acid. This is considered toxic for the brain cells and can therefore cause cognitive disorders, irritate thought processes and even affect the sense of time. This symptom also sets in after eating, after half an hour at the latest, and can persist for a few hours.
In the long term, abnormal colonization of the small intestine can lead to deficiency symptoms and weight loss, since digestion and nutrient absorption are disturbed. Vitamin B12 deficiency is often diagnosed.
The so-called ileocecal valve usually no longer closes properly when there is an overgrowth of the small intestine (SIBO). This valve is located between the large and small intestine and prevents bacteria or food from the large intestine from getting back into the small intestine in healthy people.
But why is the ileocecal valve defective? The valve usually wears out as a result of chronic flatulence. Of course, flatulence also has causes (intolerances, unhealthy diet, meals that are too large, too much fibre, unfavourable food combinations, etc.).
Also chronic constipation alone, due to slowed intestinal motility (intestinal peristalsis = intestinal movements that transport the chyme through the intestine), is enough to lead to an imbalance in the small intestinal flora.
The following factors come into question as causes of slowed intestinal motility or generally for the promotion of SIBO:
A 2018 study suggested that probiotics could cause small intestinal overgrowth, or at least make it worse. However, the subjects in question had taken excessive amounts of probiotics and in some cases were also taking acid blockers, which alone can promote the development of defective colonization of the small intestine.
In June 2019, a study was published that showed that a proper dose of probiotics (one capsule twice a day for 30 days) could even significantly improve the symptoms of small intestine overgrowth in irritable bowel patients.
So it depends on the accompanying circumstances, how the patient is doing, what medication he is taking, what other complaints he has, etc. Probiotics are therefore prescribed very individually and never in excessive quantities!
All measures that ensure a healthy gastric acid level can also protect against overgrowth in the small intestine ( healthy nutrition, eating slowly, chewing carefully, do not eat when you are stressed, taking bitter substances when there is a lack of gastric acid, avoiding stomach-damaging medication if possible, etc.).
Healthy pancreatic function is also important. This forms enough digestive enzymes for the small intestine, which in turn contain an excess of bacteria there.
The liver and gallbladder must also function properly since the bile acids also prevent overgrowth in the small intestine.
Constipation should be avoided at all costs, and one should consciously eat in such a way that one does not suffer from constant flatulence.
Basically, what is required is an overall healthy diet and lifestyle that keeps all bodily functions in a healthy balance.
Small intestine overgrowth can be detected relatively easily with the hydrogen breath test. To do this, you go (on an empty stomach) to a gastroenterological practise and are given a mixture of glucose and water to drink. The hydrogen content in the exhaled air is then measured several times (at fixed time intervals).
Hydrogen is produced in the gut when bacteria ferment incompletely digested carbohydrates. This hydrogen enters the blood via the intestinal mucosa, from there into the lungs and is then exhaled.
A hydrogen breath test, therefore, produces a sugar drink (lactose, fructose), since this would be completely absorbed in the small intestine of a healthy person. If there is an overgrowth in the small intestine, however, the sugar is fermented by the excess bacteria before it can be absorbed. This produces hydrogen.
So if the hydrogen content of the breathing air increases after 30 to 60 minutes, then the suspicion arises that hydrogen-producing bacteria are already present in the small intestine and that there is an incorrect colonization of the small intestine. If the hydrogen content of the breathing air does not change, it is unlikely that there is an abnormal colonization of the small intestine.
If the doctor has found that there is an abnormal colonization of the small intestine, then you will be given an antibiotic.
In some cases, but by no means all, the symptoms subside after taking the antibiotic, but often return after some time, so that then several antibiotic therapies have to be carried out. But even these do not guarantee long-term success. The conventional medical options for small intestine colonization are therefore still very limited so that the search for new ways is extremely important.
In May 2014, a study was published in which the effects of rifaximin were compared with the effects of herbal alternatives in patients with small intestinal overgrowth (SIBO) in various US hospitals ( 1 ). In this study, 104 patients received either 400 mg of rifaximin three times a day (67 patients) or two capsules of herbal therapy twice a day (37 patients) for four weeks – see next paragraph (two capsules of one drug and two capsules of the other drug).
In the rifaximin group, the breath test after the therapy was negative in 34 percent (17 people), which indicated that there was no longer any abnormal colonization of the small intestine. In the herbal group, however, it was even 46 percent (23 people).
14 of the 44 patients who had not responded to the antibiotic therapy now also received the herbal therapy – and 8, i.e. more than half, subsequently had a negative breath test. Another 10 of the patients who had not responded to rifaximin received a combination of three antibiotics, which worked in 6 people. The three antibiotics were: cindamycin 300 mg, metronidazole 250 mg, neomycin 500 mg.
However, the nine gastroenterologists involved in the study only concluded that herbal therapy was at least as effective as antibiotic therapy in combating SIBO. Even in people who do not react to rifaximin, herbs can be used instead of the three-way antibiotic combination.
On the side effect profile, the herbal therapy arm performed incomparably better: only one case of diarrhea was reported, while the antibiotic group reported two cases of diarrhea, two cases of skin rash (hives), one case of Clostridium difficile and one case of experienced anaphylaxis.
Many herbs or botanicals are known for their antimicrobial/antibiotic properties. Therefore, the following herbal mixtures available commercially in the US were used in the above study:
You take two capsules of one remedy (e.g. in the morning) and two capsules of the other remedy (e.g. in the evening).
The cost for a 30-day therapy with these preparations was 120 US dollars. As far as we know, the two preparations from Biotics Research are currently only available in the USA.
Below are the respective ingredients of the herbal preparations, so that you can possibly have them made in a corresponding pharmacy, whereby the exact recipe is only known from Candibactin-AR.
1. Biotics Research FC Cidal:
3. Candibactin-AR: content per capsule
4. Candibactin-BR: content per two capsules
Of course, other (simpler) measures could also work in the case of SIBO. Since there are no studies/examinations on this yet, you would have to test what is personally effective for you.
For example, you could test a low-FODMAP diet while taking zeolite or psyllium husk powder and an antibiotic herbal preparation such as oregano oil, to get started.