do probiotics work?

Do Probiotics actually work?

Written by: Kelley R. Hill, MSN, RN-BC

In a Nutshell

  • A healthy gut microbiome is important breaking down food, producing nutrients, and lowering disease risk
  • The theory is that probiotics work by boosting the numbers of beneficial bacteria and reducing harmful ones
  • Despite its popularity, there is no consensus or evidence that the commercial probiotic products have any benefit

Much of our overall health is dependent upon our gut function and health. It does much more than digest food and absorb water and nutrients. Our lower intestines are home to 100 trillion microbes that also destroy disease-causing cells, regulate our immune system, and produce vitamins. So, when there is an imbalance in those microbes, our gut gets sick, and we get sick.

Probiotics have become the third most commonly used supplement other than vitamins and minerals since 2012. It has spawned a multi-billion industry of pills, powders, and is now even offered in some foods.

  • PROBIOTICS: Probiotics are live microorganisms; many are the same as those that naturally live in our body. They help maintain the balance of the healthy bacteria in our intestines and promote healthy gut function.

Probiotics are found naturally in fermented foods like yogurt, some cheeses (cheddar, gouda, mozzarella, cottage), pickles (not brined in vinegar), miso, sauerkraut, and many other traditional fermented Asian foods like kimchi. They are also found in other fermented dairy products like kefir, as well as tempeh (fermented soybeans).

Health Claims

Supporters and some products claim that probiotics may be effective in treating myriad health conditions including skin inflammation conditions (eczema, psoriasis, rosacea, acne), upper respiratory infections, cold, flu and allergy symptoms, gingivitis, periodontal disease, and obesity. There are also claims that they can be beneficial for allergies, irritable bowel syndrome, and diarrhea.


Probiotics are generally considered safe. However, the commercially manufactured probiotics are not tightly regulated by the U.S. Food & Drug Administration (FDA ) and have to meet a lower safety threshold than approved drugs.

You should not take probiotics if you have an immune deficiency or are being treated for cancer, or if you have recently had surgery. Get guidance from a medical professional if you are breastfeeding.

Probiotics may interact with prescription drugs and antibiotics, so if you are already taking medications, consult a physician or pharmacist before starting probiotics.

Probiotics should not be considered a substitute for medically established treatments.


Conclusions are based on an abundance of good-quality, patient-oriented evidence, conducted worldwide and supported by organizations that are authorities in probiotics and intestinal health.


While a healthy gut microbiome is important to your health, there just is not enough high quality research to recommend off the shelf probiotics. Despite its rapid rise in recent years, there is just no conclusive evidence that these products show any benefit at all.


Sign up here for reminder texts that can help you stay on top of your treatment plan.

Track Your Treatment

Get notifications to more easily track your treatment plan.