The only probiotic made with 100% Lactobacillus GG.Culturelle isn’t just another probiotic. It’s the only brand with 100% Lactobacillus GG – a unique strain of probiotic that’s naturally sourced and scientifically proven. Our probiotic is the #1 clinically studied probiotic strain. That’s a difference you can trust.What exactly is a probiotic? It’s one of the good guys. Your body naturally contains billions of bacteria, heavily concentrated in your digestive system. Many of these bacteria live agreeably with your body. When non-beneficial bacteria start to flourish, however, the friendly environment can be disrupted. That’s when probiotics can help.A probiotic is good bacteria, shown to help reduce occasional problems like constipation, gas, bloating, and diarrhea by restoring the natural balance of good bacteria and non-beneficial bacteria in the digestive tract.* And, since 70% of your immune system resides in your digestive tract, a balanced digestive system can also support your immune health. Taken regularly, a proven probiotic like Culturelle will actually help your digestive system to work better.