If you’re on a quest to tackle your stomach troubles, odds are you’ve considered supplements like prebiotics and probiotics for their gut-healing properties. But while the names sound alike, they aren’t interchangeable. Knowing the difference between prebiotics and probiotics can help you build them into your diet to reap all the health benefits they provide.
For starters, pre- and probiotics are both a part of a healthy gut ecosystem, says registered dietitian Emma Willingham, RD. Your gut microbiome is the network of trillions of bacteria (including different strains of probiotics) that live in your digestive tract. An out-of-whack microbiome can cause unpleasant symptoms like gas, stomach pain, and diarrhea, according to dietitian Chelsea McCallum, who works with probiotic snack company BelliWelli. On the flip side, a good balance of gut probiotics is thought to support healthy functioning in your gastrointestinal system and beyond, including your immunity, skin health, and even mental wellbeing.
Prebiotics help fuel that healthy balance of probiotics, says registered dietitian and functional medicine expert Alana Kessler, RDN. Prebiotics are non-digestible fibers found in foods like fruits and vegetables. But while you can’t digest them, probiotic bacteria feast on prebiotics once they enter your gut.
“When we consume prebiotics, think of it as Miracle-Grow for [probiotics],” Willingham tells Bustle. In other words, prebiotics are probiotic bacteria’s food. Well-nourished probiotics are better able to flourish in your gut and balance your microbiome to promote health and digestion.
How To Get Prebiotics & Probiotics
You can consume both substances naturally through your diet, according to Willingham. High-fiber foods like onion, bananas, oats, garlic, asparagus, and apples are rich in prebiotics, while fermented snacks like yogurt, kombucha, and kefir contain tons of probiotics, adds McCallum. You can also opt to get the ‘biotics in supplement form.
If you prefer to take your pre- and probiotics as supplements, then they’re usually best served together, says Kessler. “Probiotics need prebiotics in order to not die off before reaching the end of the gut (your colon),” she tells Bustle. “It is best to take both together, as they complement each other.” Some supplements contain both and others are individual, so be sure to read the label to know what you’re getting.
But it’s possible to have too much of a good thing, says McCallum. She suggests sticking to the recommended doses of each to avoid overloading your gut with bacteria, which can cause uncomfortable digestive upset of its own. If you notice side effects like gas, stomach pain, or diarrhea, it could be a sign that you’ve overdone it or that your body is adjusting to the supplement.
Willingham recommends sticking to naturally ‘biotic-rich foods to glean all the gut-boosting benefits. “Food sources are always the safest and most effective avenues to obtain pre- and probiotics,” she tells Bustle. “You're essentially planting more healthy bacteria in your system to enhance your health.”
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Alana Kessler, MS, RDN, a registered dietitian
Emma Willingham, MS, RD, LD, a registered dietitian