Probiotics: Their long and complex journey

People spend a lot of $$$ worldwide on probiotics because of their promise of great gut health and improvements to their overall health. But do they work? When you swallow a probiotic, their journey begins immediately so let’s look at what they have to go through before they reach their destination.

Your mouth

Firstly, probiotics are subject to saliva, teeth and a mildly acidic environment. The saliva and the environment of the mouth doesn’t seem to have any effect on the cell count of the probiotics. So far so good.

Stomach

Once they are through the oesophagus, the probiotics are confronted with the acidic gastric fluid of your stomach. This acidic environment is lethal to most bacteria, especially to those who have no built in resistance to acid. This part of the journey can take anywhere between 5 mins to 2 hours and the longer it takes the worse it can be for the probiotic. Let’s not forget the enzymes and mechanics of the stomach which can also have an adverse effect on the probiotics. Research has shown that some Bifidobacterium cells can disappear in gastric juices within an hour.

Small Intestine

Next comes the bile acids and pancreatic juice! The pH is milder in the small intestine than the stomach at least, but the bile acids and digestive enzymes can affect the DNA and cell membranes of the probiotics. Some probiotics may survive this if they are encapsulated but research is still ongoing in the micro-encapsulation area.

Colon

The colon is the destination of choice for the probiotics so if they make it to this point then they deserve a medal. In the colon they will come up against the residential bacteria who may not want to let them colonise their community. He probiotics must compete for a site to stick to, and this is a hard task. Most of them get sent out on the next number 2.

So, do they work? that depends on who you ask but considering how different everybody's gut is I'd say it's hit and miss for now. In the meantime, just keep feeding the good bacteria in your gut with the right prebiotic foods to keep them happy.

Ref: https://www.frontiersin.org/articles/10.3389/fcimb.2021.609722/full