3 Brains The Gut-Brain Strain - Containing one of the most researched probiotic strains Bifidobacteriam longum BB536 to help support intestinal/gastrointestinal health. The gut brain contains approximately 100 million neurons and it can work both independently of, and in conjunction with, the head brain. Studies suggest gut microbiota communicate with the head brain and may play a role in mood and cognition. Conveniently shelf stable with no need to refrigerate.