Acid reflux is a condition in which the acid from your stomach leaks up into your esophagus (the food pipe that connects the throat to the stomach). When this reflux starts occurring on a daily basis, it is referred to as GERD (aka gastroesophageal reflux disease). GERD symptoms can interfere with your quality of life as well as damage your esophageal lining in the long run leading to inflammation and even cancerous changes within this food tube. Hence, it is important to address acid reflux in a timely manner through lifestyle modifications, medications, and alternative remedies.
One such alternative therapy that seems to be gaining a lot of momentum against acid reflux is the probiotic supplementation. But do probiotics really work for GERD? And if yes, do they offer any additional benefits when taken with the antacids or other pills used to suppress the acid production? Let’s dive a little deeper.
How do Probiotics help against GERD/Acid reflux?
Probiotics can help minimize a few GERD/acidity triggers, which, in turn, benefits the distressing GERD symptoms.
1. Help you lose some extra pounds
Obesity/excess weight is a known trigger of acid reflux.  The excess pound of flesh on your belly puts extra pressure, causing the food to reflux back up higher towards your esophagus instead of moving forward. Because probiotics can help reduce body weight through several mechanisms,  they may also help fight the acid reflux symptoms as well as keep them at bay. 
It is, however, important that you take any new supplement after consulting with your physician.
2. Restore the normal bacterial ecology of the gut
Fatty and oily foods are one of the major yet modifiable risk factors for GERD. Studies reveal that a diet high in fats alters the gut microbiome probably by causing you to put up more weight, making the gut more leaky and prone to inflammation.  We know that probiotics have a potential to reverse the microbial gut imbalance; hence, protecting you from the harmful effects of a high-fat diet and the subsequent esophageal irritation.
3. Assist in Venting out stress
The modern-day life imposes even greater psychological stress than ever. Chronic stress has been tied to GERD. A chronically stressed person becomes oversensitive and starts perceiving even milder forms of esophageal issues as severe reflux symptoms. 
As discussed in the previous posts, probiotics can communicate with your mind and alleviate stress and anxiety, thus, easing the painful reflux symptoms. 
4. May accelerate stomach emptying
A delay in the emptying of the stomach contents is one of the key culprits of GERD. The most abundant natural source of probiotics, yogurt has been shown to speed up the stomach emptying and therefore, prevent the backflow of the stomach acid into the esophagus.  While the study was conducted on people with indigestion and heartburn-like symptoms (dyspepsia), the symptoms of this condition overlap with GERD in one or more ways in clinical practice. Thus, it is not surprising to say that yogurt (in particular low-fat) can lessen the reflux symptoms.
4. Probiotics can be a beneficial add-on to acid reflux medications
High-quality probiotics offer a great deal of benefit when used along with the acid-blocking pills.
The most popular meds used to block acid production are the proton pump inhibitors (PPIs). Long-term use of PPIs can disrupt the bacterial balance of the gut. How? Research shows that PPIs suppress the stomach acid barrier that may cause small intestinal bacterial overgrowth or SIBO. This is because the acid acts as a barrier preventing the entry of harmful bacteria into the small bowel.
Remember, the small bowel is not the actual residence of bacteria but if overpopulated, this part of the gut will always grow unhealthy microbes. This is possibly what happens when you have been on a PPI for a long period. The lack (or even complete absence) of the stomach acid due to chronic PPI use may favor the overgrowth of bad bugs in the small intestine, resulting in SIBO and a messed up bacterial gut population.
According to a recent study done on the pediatric population, supplementing probiotics can restore the gut balance and combat SIBO (occurring due to the chronic use of PPIs), thereby enabling the PPIs to work effectively and relieve the acid reflux issues. . Similar mechanisms underlie PPI-induced small bowel bacterial overgrowth in adults too,  emphasizing the importance of probiotics in this age group as well.
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