Digesta-Lac® is step three in Natren's three-step custom probiotic system. This Lactobacillus bulgaricus probiotic supplement provides support throughout the digestion process*. Natren's Lactobacillus bulgaricus LB-51 super strain is a transient beneficial bacteria that travels through the digestive tract with food through the process of digestion. Each serving of Digesta-Lac® provides a minimum of 2 billion colony forming units (cfu) of Lactobacillus bulgaricus LB-51 transient super strain. Dr. Elie Metchnikoff, a Nobel Prize winning scientist who theorized that aging is caused by toxic bacteria in the gut, linked the oft-noted longevity and good digestion of the Bulgarian people to the large quantity of fermented milk products containing Lactobacillus bulgaricus in their diet. In the early 1960s, renowned Bulgarian microbiologist and researcher Dr. Ivan Bogdanov researched a variety of lactobacillus strains, focusing on their applications in improving human health.