Nearly everyone has heard about the importance of probiotics found in foods and supplements. That’s because over the past 10 or so years, researchers have generated a wealth of data about gut flora, the approximately 100 trillion bacteria living inside our digestive tract. If it’s difficult to visualize those 100 trillion organisms, trying thinking of it this way: the bacteria in your gut account for about 7 pounds of your total body mass! Those organisms contribute to a multitude of key functions ranging from digestion to immune system function.
To stay healthy, we need to ensure that our gut flora is made up of a healthy, diverse spectrum of bacteria. That’s where probiotics—which are those live “good” bacteria found in foods and supplements—come into the picture. The idea behind probiotics is to boost the numbers of good bacteria in our guts by swallowing them. And there is evidence that swallowing probiotics can lead to positive effects. However, probiotics are just one piece of the puzzle. Prebiotics, which are substances that feed and support the growth of healthy bacteria, are the missing piece.
Growing Healthy Gut Flora
“I like to think probiotics are like the grass seed for growing a healthy lawn and prebiotics are like a healthy fertilizer that you sprinkle to help grow the grass,” explains Anish A. Sheth, a gastroenterologist. In this analogy, the lawn is your gut flora. To maintain it, you must provide it with a steady supply of both probiotics (the “good” bacteria), and prebiotics, non-digestible dietary fibers that fuel the growth of the good bacteria.
Prebiotics help probiotics thrive, and have been linked to key gastrointestinal and mental health benefits. According to Sheth, prebiotics could be a promising means of treating conditions such as…
- Bloating, gas, and other digestive upsets
- Obesity
- Heart disease
- Chronic stress
- Anxiety
The Top 12 Food Source of Probiotics and Prebiotics
Both probiotics and prebiotics occur naturally in many types of foods. Any foods that are fermented but not pasteurized—this is key, pasteurization kills bacteria—contain probiotics. Some foods that fall into that category include:
- Sauerkraut
- Kimchi
- Tempeh
- Kombucha
- Miso
- Non-pasteurized yogurt and kefir
Less research has been done on prebiotics, and there’s some disagreement over the best food sources. It does seem clear that eating these foods raw maximizing the potential of their prebiotic content. The following foods have been identified as good sources of prebiotics:
- Dandelion greens
- Chicory
- Garlic, onions, and leeks
- Asparagus
- Jerusalem artichoke
- Bananas
While it’s certainly possible to meet your probiotic and prebiotic needs through diet alone, doing so would require care and planning. This is especially true for individuals whose gut health is compromised, and who therefore require higher doses to restore equilibrium. Dietary supplements might seem like the quickest, simplest way to provide your body with an adequate supply of probiotics and prebiotics, but that’s not always the case.
How to Choose the Best Probiotic and Prebiotic Supplements
Here are some rules of thumb to keep in mind when shopping for probiotics, courtesy of Dr. Tim Gerstmar, a Seattle-based naturopath, and other experts…
- The stronger, the better: while scientists have yet to identify the precise concentration
required for a probiotic to be effective, it does seem that the more organisms contained in a single dose, the better a supplement performs. Look for supplements with at least 8 billion CFUs (colony forming units) per dose. - Packaging matters: probiotics should come formulated in encapsulated pills or another type of delayed-rupture technology to ensure they make it through the highly acidic environment of your stomach and arrive safely in your colon.
- Third-party certification is the gold standard: Because almost all probiotic supplements are unregulated by the Food and Drug Administration (FDA), it’s important to seek out products that have been vetted by a reputable third party organization so you know they actually contain the ingredients listed on the label.
A good probiotic supplement should also list storage information, when relevant, and include the phrase “viable through end of shelf life” somewhere on the label. If a product reads “viable at time of manufacture,” the probiotics it contains could be dead by the time you purchase it.
Scientists don’t yet know as much about the specifics of prebiotic supplementation. “The prebiotic story is probably where we were with probiotics 15 or 20 years ago,” says Sheth. Current guidelines suggested by health experts state that a minimum recommended intake for a healthy individual is 4-8 grams of prebiotics daily. For a person with a digestive disorder, the recommended dose can be as high as 15 grams daily. Rapidly increasing your intake of prebiotics can lead to intestinal distress, so it’s best to go slowly—start with just one gram a day.
As always, your specific health needs will inform the best approach for you. Consulting with a trusted health professional is the safest way to add supplements to your wellness routine.
