Should I Take a Daily Probiotic?

Dear Anonymous,

The typical person most likely won’t need to take a probiotic, and there's no clear evidence to suggest there are benefits of probiotics for overall health or specific health outcomes. In fact, introducing a host of new bacteria via a probiotic may throw off the balance of your unique microbiome.

Think about it like this: your gut is a complex ecosystem that exists nowhere else on the planet except in your body. Now picture a rainforest with millions of species that have all evolved together to create an interdependent ecosystem. What do you think will happen if you take some random species of squirrel from across the world and plop it into that rainforest? The squirrel will either disrupt the order of the ecosystem or die off. It’s certainly not a recipe for improving the health and functioning of the ecosystem. That’s essentially what you're doing when you randomly select a probiotic off the shelf and dump it into your complex gut ecosystem and expect it to have some sort of miraculous effect. It's just not how the gut microbiome works.

There are very few instances in which a doctor might recommend taking supplemental probiotics. According to the American College of Gastroenterology’s 2020 guidelines, the evidence only supports using probiotics to prevent intestinal infections or problems in three specific groups: people taking antibiotics, premature infants, and people who’ve had surgery to remove their colon. 

This isn't to say that people who don't fall into one of those groups may not randomly stumble upon a probiotic that makes them feel better. That's possible — I hear it all the time. But the problem is that making probiotic recommendations is like throwing spaghetti against the wall and seeing if something will stick. The evidence doesn’t support that probiotics are going to do much for most people. 

For example, if you have IBS (irritable bowel syndrome), nobody can tell you that if you take this specific probiotic, it will definitely help. Most of my IBS patients who’ve tried probiotics tell me they didn't notice a difference. Some felt worse, and some felt a little bit better. It's complete guesswork. I would rather start with other interventions that I am more confident will help. 

If you’ve tried everything and nothing has worked — for IBS or something else — speak to a doctor or a dietitian who’s focused on GI issues.