A live microorganism used as a dietary supplement to help with digestion and normal bowel function. It may also help keep the gastrointestinal (GI) tract healthy. A bacterium found in yogurt called Lactobacillus acidophilus, is the most common probiotic.

Live microorganisms used to benefit health, such as the L. acidophilus bacteria found in yogurt.

Live microbial DIETARY SUPPLEMENTS which beneficially affect the host animal by improving its intestinal microbial balance. Antibiotics and other related compounds are not included in this definition. In humans, lactobacilli are commonly used as probiotics, either as single species or in mixed culture with other bacteria. Other genera that have been used are bifidobacteria and streptococci. (J. Nutr. 1995;125:1401-12)

Probiotic, any of various live microorganisms, typically bacteria or yeast, that are ingested or otherwise administered as a means of potentially aiding the prevention and treatment of certain health conditions, primarily gastrointestinal disorders. The notion that the ingestion of certain...