But there is a wide range of these supplements on the market and at different doses, making it easy to wonder how many probiotics you should be taking per day. Many of these microorganisms are the same or similar to microorganisms that naturally live in your body, although the diversity of these microbes in our body is directly affected by our consumption pattern, like how much and how often.* While there is plenty of data out there on the benefits of using probiotics, information on exact dosage—and the right amount for you—can be a little trickier.* Less often, products will report the milligram input dose instead of CFU. These doses are found on the product labels (e.g., in the Supplement Facts panel). The exact dosing can be tricky to pinpoint, given that there is no overarching recommendation. “There is no dosage that we know of, or study of efficacy that correlates to exact proper dosage of probiotics for everyone,” says Ashkan Farhadi, M.D., a gastroenterologist at MemorialCare Orange Coast Medical Center. “We know that probiotics and certain species of probiotics are important.” Their exacting dosing is a tad more cryptic. As mbg’s Ashley Jordan Ferira, Ph.D., RDN, shares, “While probiotic research is certainly still emerging in real time, the exact amount of each probiotic strain in the formula should be backed by science. In other words, if it’s a probiotic that supports gut health, each strain’s dose should correspond to some quality published literature for gut health parameters.”* Keri Gans, R.D., author of The Small Change Diet, agrees that “there is no general rule,” adding, “the amount needed may vary from person to person, depending on the reason they are taking probiotics.” But, in general, she says, you want to see a minimum of 1 billion to 10 billion CFU per strain listed on the label. “Most of us benefit from a reasonably dosed probiotic product (1 to 30 billion CFU or higher) consisting of a mixture of well-studied probiotic strains,”* registered dietitian Ella Davar, R.D., CDN, previously shared with mbg. And while mixtures, or combinations, of strains can be incredibly useful, Ferira says to look out for vague dosing on blends. “These not-so-clear ‘proprietary blends’ of probiotic strains will often share genus and species info but exclude the specific probiotic strain name(s). Furthermore, they will also share an overall CFU dose for the blend, so how is one to know how much of each strain is included? That’s not helpful to consumers.” Also, you’ll want to keep this in mind, per Erin Morse, R.D., chief clinical dietitian at Ronald Reagan UCLA Medical Center: “Higher CFU counts do not necessarily improve the product’s health effects.” “I call that the sledgehammer approach,” renowned integrative physician Robert Rountree, M.D., previously told mbg. “More doesn’t necessarily equal better. They have to be targeted. Every bacterium does different things.” As for what strains to look for, Morse says it really depends on why you’re taking probiotics. “Overall, the most common and studied probiotics are Lactobacillus and Bifidobacterium,” she says. These are overarching genus-level (genera) probiotics that she explains “help support digestion and immunity.”* For more detailed info on the different strains and what they do, see this guide. While there are plenty of foods that contain probiotics, “amounts vary from brand to type of food,” Morse says, adding that, “probiotic levels change due to time on the shelves, manufacturing, heat, and refrigeration.” Meaning, it can be tough to even know how many CFU you’re getting from a particular food, and that amount can vary based on a slew of different factors. It can also be difficult to get higher CFU from food alone, says Jessica Cording, R.D., CDN, author of The Little Book of Game-Changers. That’s why many people turn to supplements to get their probiotics. Experts stress the importance of reading the label before taking probiotics more than once a day. “If you have an instance where you need a little more support, spreading out your daily dosage to a few courses a day could be helpful,”* Cording says. You can also split up your dosage based on the form it comes in. “If the product you are taking is two or more pills per one dose, it is OK to split the dose during the day,” Morse says. For example, ½ the dose in the morning before breakfast and the other ½ dose after dinner or sometime before bedtime. Best to avoid taking with or soon after your meals, to up the bugs’ survivability (read more on that here). Just don’t exceed the recommended daily amount listed on the label unless your doctor tells you otherwise, Cording says. Still, she adds, “side effects from probiotics are very rare.” They’re usually self-limited GI issues like gas, according to NIH2. (You can read more about probiotic side effects here.) For specific recommendations, check out one of our probiotic roundups.