Yogurt and bananas makes for a great, gut-healthy breakfast.
People typically think of bacteria as a bad thing, and some of them are. Certain strains can cause illnesses and infections, but many types of bacteria actually support good health. The human body is home to around 38 trillion bacteria, most of which live in the digestive tract. It sounds strange, but many of these microbes do incredible things for your health. When supported by foods that promote healthy gut flora, they can improve digestion and strengthen immunity.
If you'd like to give your gut bacteria a boost, a diet rich in probiotics and prebiotics can help.
Each person has their own unique collection of gut bacteria—you may have a large quantity of some types and distinctly less of others. That's where probiotics come in. Probiotics are beneficial live bacteria that can help increase the number and the variety of health-promoting good bacteria already in your gut. You can get them from supplements, or try these foods.
Yogurt: Yogurt is full of probiotics like L. acidophilus, which can help keep your digestive system healthy and regular. It's not uncommon for yogurt to be recommended as a method for preventing and treating diarrhea related to antibiotics.
Tempeh: This fermented soy product is a popular protein replacement in many vegan and vegetarian diets and can also be a good source of calcium and iron. Some research has shown that tempeh can help stimulate the growth of Bifidobacterium, which may improve digestive health.
Eating probiotic-rich foods is the first step to cultivating healthy gut bacteria. However, beneficial bacteria need to be nourished in order to thrive. That requires prebiotics, which are basically food that can help good bacteria grow and multiply. Here are a few of the top sources.
Asparagus: These green stalks are packed with special prebiotics known as fructo-oligosaccharides, or FOS for short. FOS work their magic in the colon where they're fermented by the good bacteria that live there. This process can help produce potent compounds known as short-chain fatty acids that keep the lining of your gut healthy and may protect it from some diseases.
Nuts: Different strains of gut microbes have distinct benefits, so cultivating a variety is an important part of good health. To support as many different kinds as possible, snack on a small handful of nuts. While one recent study showed that munching on two ounces of nuts a day for two months may increase levels of both Bifidobacterium and Lactobacillus, more research is needed to determine their full benefit.
Whole Grains: Like asparagus, some minimally processed whole grains are also rich in FOS. Whole wheat cereal and whole oats have both been shown to have a positive prebiotic impact on gut health.
Bananas: Bananas supply not one but two types of prebiotics. In addition to FOS, they also contain resistant starch, a prebiotic that encourages the growth of healthy gut microbes while simultaneously lowering levels of unhealthy bacteria. Because ripening breaks down bananas' resistant starch, eat them as green as possible or try replacing regular wheat flour with green banana flour.
Food does more than just keep you full. With these foods that promote healthy gut flora, you can be sure you're supporting all the systems—and good bacteria—that work together to keep you well.
By Karen Ansel, MS, RDN
National Institutes of Health, Revised Estimates for the Number of Human and Bacteria Cells in the Body
ScienceDaily, Walnuts may promote health by changing gut bacteria
Mayo Clinic, What are probiotics and prebiotics?
Food & Nutrition, The Potential of Probiotics
Healthline, The 19 Best Prebiotic Foods You Should Eat
Healthline, Why Tempeh is Incredibly Healthy and Nutritious
National Institutes of Health, Clinical trial: Lactobacillus plantarum 299v (DSM 9843) improves symptoms of irritable bowel syndrome.
Today's Dietitian, Entering the World of Prebiotics — Are They a Precursor to Good Gut Health?
National Institutes of Health, Prebiotic nut compounds and human microbiota
National Institutes of Health, Whole-grain wheat breakfast cereal has a prebiotic effect on the human gut microbiota: a double-blind, placebo-controlled, crossover study.
Food Navigator, Green banana flour: A powerful new tool in the digestive health toolbox?
These articles are not a substitute for medical advice, and are not intended to treat or cure any disease. Advances in medicine may cause this information to become outdated, invalid, or subject to debate. Professional opinions and interpretations of scientific literature may vary. Consult your healthcare professional before making changes to your diet, exercise, or medication regime.