Probiotics Can Cause Brain Fogginess, Bloating and Gas


In a study conducted by the Medical College of Georgia at Augusta University researchers have discovered a significant amount of bacteria in the small intestine from probiotic use which may result in disorientating brain fogginess and rapid, severe belly bloating. The study was conducted on 30 patients with 22 of them reporting problems with difficulty concentrating and confusion. They also reported bloating and gas.

The researchers discovered large colonies of breeding bacteria in the patient’s small intestines and high levels of D-lactic acid which was being emitted by the bacteria lactobacilus sugar fermentation in the food they consumed. D-lactic acid can be somewhat toxic to brain cells which can interfere with thinking, sense of time and cognition. Some of the patients in the study showed over two times the adequate amount of D-lactic acid in blood levels. Most of the patients said the brain fogginess they were experiencing lasted from half an hour to several hours after a meal and some reported that the fogginess was so extreme that they had to quit their employment.

This is the first time that the similarities have been made between the overgrowth of bacteria in the small intestine, top levels of D-lactic acid in the gut, and brain fogginess associated with probiotic use. Probiotic bacteria can break down sugar thus producing D-lactic acid. If the small bowel is inadvertently formed with probiotic bacteria then the stage has been set for possibly developing lactic acidosis and fogginess of the brain. Probiotics can be very helpful in some instances such as restoring the bacteria in the gut after taking a course of antibiotics, but with excessive or indiscriminate use complications such as noted in the study can arise. The researchers warn that probiotics are a drug and should be treated as one other than a food supplement.

The patients in the study who experienced brain fogginess took protiotics and small intestinal bowel overgrowth (SIBO) was more prevalent in this group (68% compared to 28%),. The patients with fogginess of the brain also showed a higher evidence of D-lactic acidosis (77% compared to 25%). When the patients experiencing the brain fogginess stopped taking the probiotics and instead took a course of antibiotics, their fogginess of the brain was resolved. The actual food movement in the gastrointestinal tract slowed in one third of the patients with brain fogginess and one fourth in another group. Slower food passage may increase the occurrence of SIBO.

Normally the small intestines make little amounts of D-lactic acid. SIBO may change that by causing a bacteria feeding frenzy which causes sugar fermentation resulting in methane and hydrogen gas that causes bloating. When probiotics are added in the acid gets pulled into the blood and can be delivered to the brain.

By identifying the problem, it can be treated. Diagnosis includes urine, blood and breath tests to detect lactic acid and an endoscopy which examines fluid from the small intestine can identify the specific bacteria and antibiotic treatment can be administered.

In the study, the patients with brain fogginess, SIBO and/or D-lactic acidosis were asked to discontinue probiotic products and were given antibiotics which were targeted to their bacterial population. Those patients who did not exhibit SIBO were asked to stop probiotics and stop eating yogurt. Those patients with SIBO and D-lactic acidosis but no fogginess of the brain were also administered antibiotics. After treatments, three-quarters of patients responded with significant improvements in their symptoms. 85 percent of patients reported their brain fogginess had disappeared. Those patients with SIBO and top levels of D-lactic acid and no fogginess of the brain reponded significantly with improvement in regards to cramping and bloating with three months.

All patients who participated in the study had intense examination of the gastrointestinal tract which included a motility test which ruled out any other potential causes of their symptoms. Questionnaires were filled out which included questions about symptoms such as belching, gas and abdominal pain along with other related issues about probiotic and antiobiotic use and food trends and consumption of yogurt.
Patients ate carbohydrates which were followed by metabolic testing to see the impact of things like insulin and levels of blood glucose. Measurement of D-lactic acid and L-lactate acid levels were looked at in proportion to acids, which result from muscle use of glucose for energy can also create muscle cramps.

Probiotics are meant to be beneficial in the colon and not in the stomach or small intestines. However, people with motility issues, those taking opioids and proton pump inhibitors, may result in issues with probiotic bacteria entering the proper place. Other problems from use of minerals like iron and antidepressants and people with diabetes, can also increase the change and slow movement that probiotics will remain too long in the upper intestine where they may cause harm.

For many people probiotics can help especially in those suffering from stomach flu or gastroenteritis where diarrhea and subsequent problems from antibiotic use can wipe out a persons natural gut bacteria. This is when probiotic use is beneficial in building up the bacterial flora. Sources of good probiotics are sauerkraut, yogurt, kefir, kimchi and dark chocolate. These are all generally safe due to the bacteria being in small amounts. Gut bacteria that is helpful or microbiome are important to oerall general health and a well functioning immune system.

Future studies will include following patients for longer periods of time to ensure problems remain resolved. Some of the patients in the current study required two rounds of antibiotics.

To view the original scientific study click here: Brain fogginess, gas and bloating: a link between SIBO, probiotics and metabolic acidosis.