If you have ever walked down the supplement aisle or scrolled through wellness trends online, you have seen the word probiotic everywhere. We are told to take them for "gut health," but a major piece of information is often left out: probiotics are not a one-size-fits-all fix. Taking a generic probiotic supplement and hoping it fixes your specific bloating, fatigue, or irregularity is a guessing game. To get real results, you need to understand the different types of probiotics—or strains—and exactly what jobs they do in your body.