What are fermented foods? 

Fermented food and drink products have become popular recently. But the process of fermentation has been around for centuries, long before refrigeration, to help protect foods from spoiling, make them last longer, and enhance flavor! 

Fermentation happens through the breakdown of the sugar and starches found naturally in foods, causing them to function as natural preservatives, similar to alcohol or acids. In addition to preservation, fermented foods can add nutritional value through a healthy dose of “probiotics,” which are helpful for good digestion. 

Some examples of fermented foods are 

  • yogurt
  • kefir
  • tempeh
  • sauerkraut
  • kimchi
  • miso
  • kombucha tea

When we eat enough of the live microorganisms from these products, they can be a health benefit to us. 

Why are fermented foods good for you? 

Fermented foods are good for you because they can provide a source of probiotics to those who eat or drink them regularly. Probiotics can support the bacteria living within us and have the potential to protect against pathogens, or the “bad” infection-causing bacteria in our body. 

Probiotics are also thought to bolster our immune system and affect many of our physiological functions. Although many of the health benefits of probiotics have yet to be proven, the literature continues to expand. 

What are probiotics? 

A probiotic is defined by the World Health Organization (WHO) and Food and Agriculture Organization (FAO) of the United Nations as a “live microorganism that, when administered in adequate amounts, confers a health benefit on the host.”

Probiotics can be found in many fermented foods, previously discussed, as well as some dietary supplements available at your local pharmacy. Probiotics are not all the same or considered equal. Different probiotics are known by their genus, species, and strain name and should be labeled accordingly on the product you purchase. 

It is important to be mindful of the amounts of probiotics in the products you choose. More does not always mean better. Probiotics are measured in colony forming units (CFU). One probiotic strain might be beneficial at two billion CFU, while another strain may need 60 billion CFU twice daily for its intended use. 

Because probiotics are live cultures, they should be clearly labeled with a “best by” or “expiration" date and not consumed after this timeframe. It is also worth mentioning that there are no Food and Drug Administration (FDA) approved probiotic products available. What you see in your pharmacy are considered over the counter “dietary supplements.” The FDA is not authorized to review dietary supplements for safety and efficacy prior to marketing. You can learn more here

Dietary supplements can differ in quality, purity, and consistency from what is labeled on the packaging, leading to inconsistencies in dosing. It is up to the manufacturer to ensure the product they market is safe and without misleading claims. Packaging for dietary supplements must clearly state, “These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.”  

To be clear, not all fermented foods contain live and active cultures that can qualify as probiotics. Processes such as pasteurization, smoking, and filtering can kill or remove the live cultures from fermented foods, making them ineffective. 

What are microbiomes? 

Microbiomes are collections of species of bacteria, archaea, viruses, and fungi living within us and on us, especially within our gut. The human intestine harbors trillions of bacteria, named our “gut microbiome.”

We may have been taught as children that bacteria are bad for us, but this is far from the truth. The truth is that some bacteria are “bad” or pathogenic (infection-causing), some are “good” or commensal (meaning they have a mutually beneficial relationship with the host), and some are neutral. While we do not yet know what constitutes the ideal gut microbiome, scientists agree that the balance of these many microbes residing within our gut is important to our health. 

How do probiotics affect your gut health? 

It remains unclear whether probiotics will play a therapeutic role in gastrointestinal diseases. At this time, there is not enough evidence to recommend the use of probiotics for specific conditions; however, research shows there may be potential for some. 

Probiotics, either from food sources or dietary supplements, are reasonably safe to consume for most healthy individuals. Discuss with your doctor or pharmacist if you believe you might benefit. 

What are the side effects of probiotics?

The most common side effects of probiotics include minor cramping, nausea, soft stools, flatulence, and taste disturbance. While rare, there have been case reports of serious systemic infections in high-risk immunocompromised patients, and therefore people who meet this description should be especially careful and not use probiotics without first talking with their doctor. 

The International Scientific Association for Probiotics and Prebiotics (ISAPP) is a great reference for consumers and healthcare professionals alike for the most up to date evidence-based recommendations. 

Alissa Margraf, PharmD

Alissa Margraf, PharmD, BCACP, CDOE

Alissa Margraf is a clinical pharmacy specialist with the Lifespan Pharmacy.