With gut health and the microbiome becoming trendy in the wellness world in recent years, probiotic foods have also become a topic of conversation.
Officially speaking, the term probiotic refers to live organisms in amounts known to provide health benefits. You can score probiotics through supplements and certain fermented foods, though not all fermented foods can be characterized as containing probiotics.
Learn why you should be getting probiotics from your food and how to tell which ones have them.
What are probiotics?
Probiotics are good bacteria that help maintain a healthy balance in the gut. Everyone’s gut is unique — like a fingerprint — but one of the most important features of a healthy gut is the diversity of microbes that reside there. Think of these beneficial bugs as having unique jobs, so you need many different critters to form a strong team.
Are probiotics good for you?
Yes. The varied roles of probiotics include producing certain vitamins or help you absorb nutrients better, aiding in digestion and keeping bad microbes from causing harm. Your gut environment is intricately tied to your physical and mental health. For instance, the majority of your immune system cells originate in the gut, as do most of your mood-regulating chemical messengers. Aside from these general benefits, certain bacterial strains may have specific perks, such as relieving constipation or traveler’s diarrhea, or helping with stress and anxiety.
What are fermented foods?
Fermented foods are made using microorganisms, such as bacteria, yeast or mold. Fermented foods include yogurt, kefir, kombucha, cheese, pickles, sauerkraut, kimchi and sourdough bread. However, depending on how the product was produced, the microbes may or may not be present in the final product. For example, heat destroys microbes, so the live cultures aren’t present in baked goods (such as sourdough bread) or canned sauerkraut. Technically, wine and beer are fermented, but unless you’re buying a specialty product, there’s a slim chance your booze contains live active cultures.
Meanwhile, there’s promising evidence that consuming fermented foods with live active cultures can help improve your gut and overall health. Research has tied these foods with better metabolic health, such as improved fasting blood glucose and healthier triglyceride levels. A 2021 study by Stanford University researchers found that consuming six servings of fermented foods daily for 10 weeks led to a boost in microbiome diversity and lower levels of inflammatory markers associated with conditions including stress, Type 2 diabetes and rheumatoid arthritis.
What’s the difference between probiotic-rich foods and fermented foods?
Here’s where things get a little bit tricky. While many people refer to live cultures as probiotics, the agreed-upon scientific definition states that a probiotic is a live organism in an amount that provides a health benefit. The live organism is further characterized by the genus, species and strain.
So, some foods, including certain fermented foods, like yogurt, as well as dried fruits, snack bars and more, may be enhanced with a particular probiotic strain. These are examples of probiotic-rich foods. Other foods, such as fermented foods, may be rich in live and active cultures, but if the strain and amount aren’t known, they aren’t characterized as probiotic-rich foods. Even so, regularly eating various fermented foods has been found to improve gut health, so it’s not necessary to get caught up in the lingo.
The 10 best probiotic foods
- Low-sugar yogurt
- Cottage cheese made with live and active cultures (most brands don’t contain them, so look for it on the label)
- Refrigerated sauerkraut
- Miso paste
- Refrigerated pickles
- Unpasteurized cheeses, including Swiss, provolone, and cheddar
How to shop for and eat probiotic-rich and fermented foods
The term probiotic isn’t regulated on a food label, so your best bet is to choose fermented foods that haven’t been subjected to heat (say, refrigerated sauerkraut instead of the shelf-stable canned variety) and fermented dairy foods that list "live active cultures" on the label. For yogurt and kombucha, try to choose types that have little to no added sugar since a high-sugar diet has been linked with unhealthy changes in the lining of the gut wall and microbial community.
Here are some ways to eat a variety of gut-healthy foods daily:
- Include a lower-added-sugar yogurt with breakfast. Have it with fruit and nuts, blended into a smoothie, spread over whole grain toast or mixed into oatmeal.
- Snack on drinkable yogurt, kefir and cottage cheese that contains live active cultures.
- Add sauerkraut to sandwiches, burgers, scrambled eggs and avocado toast. You can also blend it into your favorite fruit and veggie smoothie.
- Sip on lower-added-sugar kombucha.
- Use the liquid brine from fermented veggies to make a salad dressing or sandwich spread.
Who should eat probiotic-rich and fermented foods?
Most people benefit from gut-healthy foods. Unless you have a food sensitivity or intolerance to one (or more) fermented foods, there’s no real downside to eating them other than perhaps being unfamiliar with ways to enjoy them. The best evidence suggests aiming for six servings of fermented foods daily. If this sounds unmanageable, consider that serving sizes may be smaller than what you’d expect. In the study, a serving of kombucha and yogurt were 6 ounces; meanwhile, a typical bottle of kombucha might have two to three times that amount. A serving of fermented veggies equaled one-quarter cup.
More tips for improving your gut health
Eating probiotic-rich and fermented foods can help improve your gut health, but it’s not a one-and-done strategy. Your gut community needs additional support. The best ways to nourish your gut also include these strategies:
- Fill your plate with at least 75% plant foods. This amount helps ensure you meet the fiber target of 21 to 38 grams per day. Plus, plant foods are rich in prebiotic fibers and polyphenols that help feed your gut microbes, enabling them to thrive.
- Diversify the plants on your plate. One study found gut health benefits, such as a more diverse microbiome and a reduction in certain antibiotic resistance genes, among people who ate 30 unique plant foods per week compared to those eating ten or fewer different types of plants. If you’re overwhelmed by that amount, consider that spices, coffee, tea, oats, brown rice, beans, nuts, seeds, fruits and veggies all count.
- Get sufficient activity. There’s evidence that moderate exercise can increase microbial diversity, lower inflammation and reduce intestinal permeability, which are signs of a healthy gut.
- Sleep for seven to nine hours each night. Researchers have found an interplay between sleep and gut health, noting a positive correlation between microbiome diversity and increased sleep efficiency and duration.
- Find helpful ways to cope with stress. Stress can affect your gut permeability and negatively alter your microbial community.