7 Good-for-You Reasons to Add Fermented Foods to Your Diet ASAP

Gut health is so important. Keeping your gut microbiome balanced with "good" and "bad" bacteria affects your whole body. A healthy gut not only aids in digestion, but it also has an impact on your body's other systems, like your skin, cardiovascular system, and immune system, to name a few.

To make sure your gut is at its healthiest, you can do a number of things. Taking supplements, such as probiotics, can help. You can also make changes to your lifestyle habits, like getting enough sleep, managing your stress, and quitting smoking. But the best way to manage your gut is to start with a healthy diet. That's where fermented foods can come in handy.

"Fermentation happens when microorganisms such as bacteria or yeast convert carbs or sugars into ethyl alcohol, lactic acid, or acetic acid," explains Tamar Samuels, MS, RD, CDN, a registered dietitian, national board–certified health and wellness coach, and co-founder of Culina Health. "This natural process acts as a preservative for the food and also encourages beneficial bacteria to grow in the case of lactic or acetic acid production."

All of this results in probiotics being present in fermented foods or drinks, says Steven Gundry, MD, author, medical director at the International Heart and Lung Institute, and founder of Gundry MD. "The byproducts of fermentation, the dead bacteria and fungi, and the living organisms all have potential effects on the organism (us) that ingests the fermented food or the resultant beverage," he adds.

More research needs to be done to better understand the specific health benefits of fermented foods and how they work to support us, says Yasi Ansari, MS, RD, CSSD, a national spokesperson for the Academy of Nutrition and Dietetics. But here's what we do know so far.

Some examples of fermented, or probiotic-rich, foods include sauerkraut, kimchi, kombucha, yogurt, kefir, apple cider vinegar, miso, some wine, and aged cheeses. "There is interesting new research that the process of prolonged soaking of beans and lentils promotes fermentation of the lectins in beans, making them a fermented food as well," Gundry adds.

While those probiotic-rich foods can help, adding in prebiotics helps it all come together. "Prebiotics are just as important—these guys actually feed the existing bacteria in the gut," explains integrative health expert Mackenzie Piccarreto. "Most supplements will include prebiotics as well, but in terms of food, bananas, garlic, and onions are some great options."

This one isn't surprising, but it's a big benefit. "Fermented foods can help promote the growth of beneficial bacteria (probiotics), which can help support digestion and our immune health," Ansari explains. "More information is needed for specific bacteria strains, but you can start with a food-first approach that offers a variety of bacterial strains."

Samuels adds that research has shown that probiotics can help with digestive problems like diarrhea, constipation, and bloating as well as gastrointestinal conditions like IBS, Crohn's disease, and ulcerative colitis.

"Fermented foods contain living beneficial bacteria, which directly support our gut," explains Piccarreto. "As we know, the gut is truly the center of well-being in the body. It plays a huge role in digestion, nutrient and mineral absorption, and protecting us against 'bad' bacteria. Our immunity is also a factor, as 70% of our immune system is actually located in our gut."

Because probiotics can benefit immunity, Samuels explains that they have also been successfully used to treat infections, including UTIs, bladder infections, GI infections (like H. pylori), and clostridium difficile.

While more research is needed, Samuels says there is some evidence that probiotics can be helpful for weight management. 

"Some of the other benefits of fermentation include enriching the protein content and micronutrients," Ansari says. Fermentation can also increase the bioavailability of nutrients.

Gundry says some strains of bacteria have been shown to improve skin appearance and hair growth—some of which are included in Gundry MD's BioSkin Youth Complex supplements.

Fermented foods might also play a role in managing skin conditions such as eczema, psoriasis, and acne. "These skin conditions are associated with an imbalance of harmful and beneficial microbes on the skin and inflammation, both of which are potentially improved by introducing more beneficial microbes like probiotics," Samuels explains.

Good news for some of you out there who can't tolerate gluten. "Non-celiac gluten sensitivities may be able to tolerate breads that have gone through the fermentation process," Ansari says.

It seems that the benefit extends to those who are lactose intolerant, too. Ansari adds that fermentation helps make dairy more digestible for those who may not be able to tolerate as much lactose in non-fermented milks.

"Fermented foods should be regularly included into your diet for a very healthy gut!" says Vanessa Rissetto, MS, RD, CDN, a registered dietitian nutritionist and co-founder of Culina Health. "A great beginner's tip to fermented foods is adding kefir into your smoothie or trying kombucha for a midday beverage. Sauerkraut can be used as a topping to salads and main courses; yogurts make a great snack and/or breakfast. Prebiotics are foods that 'feed' the good bacteria in your gut, such as garlic, banana, asparagus, and whole grains. Because they promote the growth of these beneficial bacteria, an amazing way to incorporate the prebiotics and the fermented foods with probiotics into your diet is to have a meal or snack with the two foods together, such as yogurt with banana."

If you're beginning to add fermented foods to your diet, Rissetto recommends starting slowly, as too much can cause gas and bloating.

When shopping for fermented foods, you'll want to look at the labels closely. "Check that the packaging says 'naturally fermented' if you are looking to include probiotics in your diet," Rissetto explains. "There are some other processes for fermenting that do not include live organisms in the fermenting process." You can also look for labels that say "live active cultures," too. You'll also want to switch up the types of probiotics you're eating. Rissetto says this helps you give yourself healthy and differentiated microbiota.

As for preparing or serving these foods, Ansari says that you should keep in mind that microbes in these foods can be destroyed with processing like heat.

While the experts agree that most people can benefit from adding fermented foods to their diets, there are a few things to be mindful of. "If someone is immunocompromised, they should take precautions when consuming certain fermented foods, as there is evidence that some pathogenic bacteria can survive the fermentation process in fermented foods like sauerkraut," Rissetto says. "Those with yeast allergies might want to stay away from some fermented foods as well. If you are recovering from SIBO (small intestine bacterial overgrowth), you should also limit your intake of fermented foods."

Gundry adds that he occasionally sees patients consuming a lot of kimchi or sauerkraut, suppressing their thyroid function. So the main takeaway? Everything in moderation.

Next up: The 6 Signs of Poor Gut Health and What to Do About It