By Meigan Freeman, UC Davis Nutrition Peer Counselor
Probiotics, prebiotics, and now synbiotics? What are these biotics and what can they do for your health; or are they just another health scam that ultimately burdens your wallet? I’ll go through their purposes, food sources, and possible benefits. But first, let’s review our gut bacteria, an important part of probiotics.
Your colon hosts millions of bacteria, which scientists refer to as the gut microbiome, which help you digest food, heighten your immune system, and give you essential nutrients. In fact, they contribute more genes towards human survival than humans themselves do! We have evolved with them and without these important symbiotic bacteria, humans would not be able to survive. We are completely dependent on them. (Consider reading my other post on bacteria and the microbiome for a deeper dive!)
We have established how important our gut microbiome is to our survival, so shouldn’t we do everything we can to keep them alive, including eating all the probiotic supplements we can? Not quite. The human body has long evolved and survived healthfully without supplements, so I wouldn’t be too eager to start taking them now. But I have gotten ahead of myself, we need to define and differentiate between probiotics and prebiotics first. Probiotics are live bacteria which are ingested and intended to promote health. They naturally occur in fermented food products, like yogurt, kefir, and kimchi, and can also be taken as over-the-counter supplements. On the other hand, prebiotics are not living organisms, but rather food particles that feed and support the life of the bacteria which already live in your gut. Oligosaccharides, mainly fructooligosaccharides (FOS), galactooligosaccharides (GOS), and inulin are carbohydrates that cannot be digested by humans, but support healthy strains of bacteria in our gut. These oligosaccharides can be naturally found in many fruits, vegetables, and beans and are a significant part of many people’s diets around the world. Synbiotics are only contained in supplements and are a mixture of both prebiotics and probiotics. Providing probiotics (living bacteria) with prebiotics (food source) make the probiotics live longer and become more shelf-stable.
As touched on earlier, probiotics and prebiotics are naturally found in many types of food that you probably already eat. Fermented products like yogurt, kefir, kombucha, sauerkraut, pickles, miso, tempeh, kimchi, and sourdough bread contain probiotics while prebiotics are found in nearly all fruits, vegetables, and beans. Because probiotics and prebiotics are available in many different types of food, I personally do not see a need in taking supplements. However, if you have certain digestive disorders or a very limited diet, a dietitian may recommend you to use such supplements. Remember, what is healthy for me is not necessarily healthy for you! Health is a very individualized process.
A healthy microbiome can be marked by healthy digestion. If you have a regular poop cycle, your microbiome is probably very happy! Sometimes our cycle gets out of whack and we get sick with diarrhea or constipation for whatever reason. Thankfully, probiotics have been the most researched for their prevention of diarrhea and constipation, including people who have IBS, IBD, and even traveler’s diarrhea. An increased intake of fermented foods may be helpful during or after bouts of sickness to reestablish a healthy microbiome. Other probiotic claims, such as their effects on obesity, aging, and diabetes need to be further researched before any definite declarations can be made.
Overall, probiotics and prebiotics are not a scam. They are definitely real and can have real benefits. Fermented foods have been consumed for thousands of years across multiple geographies and cultures across the globe. However, not everyone needs to take supplements, in fact, most people probably don’t need to take them! As a rule of thumb, it is usually better to get nutrients, including probiotics, from whole foods, rather than supplements, because whole foods are richer in vitamins, minerals, antioxidants, fiber, and other important nutrients.