We’ve all seen those TV commercials touting the many health benefits of foods and supplements that contain probiotics. They now even have probiotic supplements for kids! In fact, a few years ago, when my youngest was 1 year old, her pediatrician recommended giving her a probiotic powder in her bottle to help with a particularly bad case of diarrhea. It did stop right away. Whether that was because of the probiotic or because it had just run its course, I’m not sure.
I haven’t given either of my kids probiotic supplements since, but I just recently encountered some students here in my department who were talking quite passionately about the health benefits of probiotics. I started wondering – should I be giving my kids probiotics, and maybe even taking them myself? Are probiotics even safe for adults to take? And what about for kids?
First, why might we need probiotics?
We used to think that our digestive system had only one job – to digest food. We couldn’t have been more wrong. It turns out that the digestive system is one of the most important parts of the body! Not only are there cells in there that help to absorb nutrients from food, there are also immune cells.
These immune cells fight infection in the gut, but even more importantly, they send signals out of the digestive system to regulate immunity and general health in the rest of the body. Some say the digestive system controls basically every part of us!
Along with those cells, we also have bacteria in there. We tend to think bacteria are bad for us, but there are many types of bacteria that are harmless, and even good for us. The mixture of those bacteria in us is called our microbiome. The types of bacteria in your microbiome determine how well you digest food, and how well you fight disease.
So why might we need probiotics? If our microbiome gets out of balance, meaning that there aren’t enough of those good bacteria in there to keep us healthy, then we may get sick.
Scientists think that adding probiotics, prebiotics, or synbiotics to our diets can help keep that healthy microbiome, and prevent a variety of illnesses.
What is the difference between probiotics, prebiotics, and synbiotics?
With all of the different products on the market, it’s hard to know what they even are, and how they’re different. Here’s what you can find:
Probiotics = Live Good Bacteria
According to the World Health Organization (WHO), probiotics are “live strains of strictly selected microorganisms which, when administered in adequate amounts, confer a health benefit on the host”. This means that, to be called a probiotic, the supplement or food must have bacteria that are not only harmless, but are beneficial to health. Not only that, they must be present in large enough numbers to have that positive health effect.
Here are some of the positive health effects of probiotics that are supported by scientific studies:
Prebiotics = Bacteria Food
The good bacteria in your digestive system do better when they have the right nutrition for themselves. The high amounts of processed, sugary, and fatty foods in our diet may not be very good for maintaining those good bacteria in high numbers. Prebiotics are supplements that can help to support the growth of the beneficial bacteria in your system. Studies suggest that you can use these instead of probiotics and get some of the same positive effects on your health. This could be good if you are concerned about introducing a supplement containing live bacteria into your system (though a large number of studies agree that probiotics are safe to take).
Here are some natural foods where you can find the prebiotics that you would find in supplements currently on the market:
Synbiotics = Live Bacteria + Bacteria Food
More recently, scientists have combined probiotics and prebiotics together. The prebiotics support the growth of the good bacteria that you already have. They also help the probiotic supplements to survive in your gut long enough to confer beneficial effects on your health. The thing that makes these synbiotics better than just taking both probiotic and prebiotic supplements is that the synbiotic supplement is specially designed to provide the probiotic in the supplement with it’s optimal prebiotic food. Theoretically, that should more effectively help the probiotic bacteria to survive than just a general prebiotic would.
Are probiotics safe for Adults? What about for Kids?
There have been extensive studies that explored whether probiotics are safe in infants, children, and adults. The overwhelming evidence shows that there do not appear to be any real risks associated with taking probiotics. They even appear to be safe for immunocompromised individuals to take. As a result, the Food and Drug Administration (FDA) considers probiotics to be “generally recognized as safe”. However, because probiotics are considered dietary supplements, they are not actually regulated by the FDA. Also, each product on the market contains slightly different strains and amounts of bacteria, and not all of these have been extensively tested.
There are a million products out there. How do I choose one?
The choice of which probiotic is best to take can actually be a very complicated decision. Each strain of bacteria can confer different potential benefits, and each product on the market can contain a variety of different bacterial strains. The names of those bacteria contain three parts: the genus, the species, and the strain.
The genus is sometimes abbreviated to its first letter. Lactobacillus rhamnosus GG (or L. rhamnosus GG) is the strain that has been most extensively studied. This strain has a variety of beneficial health effects and, as a result, appears in many of the probiotics on the market. Other bacterial species have demonstrated health effects as well. In addition, some think that taking a supplement with multiple species in it, or a synbiotic, is better. However, there isn’t enough research yet to say definitively which is best. Here are some bacterial species and the beneficial effects they had in scientific studies.
When choosing a probiotic, it is best to consider the reason you are looking to take the supplement. Based on the chart above, if you are trying to prevent or treat diarrhea, a supplement that contains L. rhamnusus GG or S. boulardii would probably be best. If your infant has ezcema, L rhamnosus GG or B. lactis may help. However, while the products on the market contain the same species of bacteria as were tested in these studies, the strains may not be exactly the same, so there is no guarantee of the same benefit.
Below are some common probiotics on the market and the bacterial strains they contain:
Does this mean we should take daily probiotic or synbiotic supplements?
I was impressed with the large number of studies testing the safety of both long and short-term use of probiotics. These convinced me that taking these supplements is not likely to harm you. In addition, probiotics do seem to confer a variety of health benefits. The number of studies supporting this is growing every day. In particular, taking probiotics when on antibiotics or when suffering from a stomach bug could help to keep your gut microbes in balance. But we still need more research on the proper dosages that are most effective, and the effectiveness, and even safety, of the different strains on the market. I asked Mohamad Mortada, a graduate researcher in the Poultry Science Department at the University of Georgia and an expert on probiotics, what he thought about taking probiotics. He had some excellent advice. He said:
“It is always good to keep in mind that you are taking your probiotics and prebiotics as an insurance policy. It might be useful for you and your specific situation, and it might not benefit you at all. But the good thing is that it is not likely harmful (Generally Regarded As Safe).”
So it seems that we could put this in the “can’t hurt” category until more testing is done. This research has convinced me to try probiotics, at the very least, when we have bouts of the tummy troubles. Who knows? It might just help.
Note: The information in this post should not be considered medical advice. Please consult your doctor when considering the use of any dietary supplements.
