21st Century Probiotics contains “friendly bacteria”, of four types : Lactobacillus Acidophilus - 100mg, Lactobacillus Salivarius - 100mg, Bifidobacterium Bifidum - 100mg, Streptococcus Thermophilus - 100mg. The 8 Million freeze-dried friendly, health giving bacteria culture in each capsule will come alive when it comes into contact with water. This is much, much more than what you can ever get by daily food consumption. So taking Probiotics capsules is a way of getting the health benefits of friendly bacteria.