Are Probiotics Actually Helpful Or Just Hype? A Microbiologist Explains The Science

Chances are, you probably have a few questions about probiotics—or bugs, as researcher Zac Lewis refers to them. Lewis holds a Ph.D. in microbiology and is currently a scientist at Renew Life, the company behind the No. 1 women's probiotic, so we tapped his expertise to answer the most common questions and clear up some misconceptions. Here's what he had to say.

I think lots of people understand that probiotics are "good for you," but they maybe don't really know what a probiotic is. Probiotics are formally defined as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host." That means that probiotics have to be alive, they have to be at the right dose, and there needs to be proof that they help your health; otherwise, they're not probiotics but something else.

If a product has dead bugs in it, it's not a probiotic. If it's just fairy dust amounts of live bugs that aren't effective, it's not a probiotic. If it has no proof that it helps you, it isn't a probiotic. That proof usually needs to be from a rigorous clinical trial that shows the live microbe works better than an inactive sugar pill, aka a placebo.

Probiotics can work in different ways. Some types—or "strains" in science-speak—work by talking to your immune system in specific ways that make you more resistant to challenges. Some calm down an immune system that is overreacting to things it doesn't need to. Others work by interacting with your digestive tract to affect the speed at which food moves through you—it's never pleasant to have your gut working too fast or too slow! Some strains work by settling down in your intestines and helping to crowd out bad bugs by taking up all the space and eating all the bad bugs' favorite foods. Some even actively kill the bad bugs for you!

You can also look at the list of the probiotics themselves. Different strains can offer different benefits, so products containing multiple strains may be able to offer you more benefits. You also want to use the right bug for the type of benefit you want. Just like German shepherd dogs make good guard dogs and chihuahuas make good lap dogs but not vice versa, you wouldn't want to use a probiotic native to your mouth to solve occasional constipation, and you don't want to use a strain that colonizes the large intestine if you want to support your vaginal health.

The most important factor in taking probiotics is that you actually take them! This means you should find a time of day when you can incorporate taking your supplement into your routine so that you remember to do it every day.

As far as storage, you should follow the directions on the packaging. Some probiotics require refrigeration, and most would benefit from refrigeration since it keeps them fresh. However, some products are formulated to be shelf stable and can be kept at room temperature on your table, in your medicine cabinet, or in your purse for on-the-go use!

However, sometimes probiotics help with things that are more preventive by helping you maintain health, such as by preventing future respiratory tract problems or future occasional diarrhea. The proof that it is working is that you experience fewer disruptions over time. The best efficacy assurance you can have before buying the product is knowing that it is backed by rigorous clinical trials that you can trust.

By far the most exciting things happening right now in my opinion are in the "microbiome" field. A microbiome refers to the microorganisms in an environment. There are around 40 trillion bacteria living in and on each and every person, which is about as many human cells as a person has! Scientists are quickly figuring out what types of microbes there are in our microbiomes and what they're doing.

I like to compare the human microbiome to other "ecosystems" that people are more familiar with. Where one person might have a lush tropical jungle-like microbial community in them, another person might have a barren desert-like microbial community in comparison. We're discovering that different microbes play different roles in their community and that a healthy microbiome requires balance.

So just as cows need plants to eat, wolves can help keep deer populations under control, and plants need bees to help pollinate flowers, different microbes prefer different foods, and healthy functional microbiomes need lots of different species competing and cooperating to be stable. Diversity is usually a good thing for an ecosystem to have!