Probiotic bacteria for human nutrition are generally strains of lactic
acid bacteria or bifidobacteria. The beneficial effects of these stra
ins on human health and well-being are documented in experimental and
clinical studies. Lactobacillus (casei subsp.) rhamnosus GG (ATCC 5310
3) is a probiotic strain of human origin. The strain has most of the c
haracteristics generally proposed for a good probiotic strain, includi
ng excellent survival in the stomach and small intestine and transient
colonization of the gastrointestinal tract, which is based on its adh
esion capacity to intestinal cells. Successful recovery of the strain
in stool samples has made dose-response studies possible and enabled t
he evaluation of effective dosing using food products. The beneficial
effects of the strain have been shown in many types of intestinal dist
urbances caused by pathogenic bacteria and viruses, as well as in prop
hylactic use. The latest studies on Lactobacillus GG have shown stabil
izing effect on gut permeability and suppression of allergic reactions
in food hypersensitivity. The safety of Lactobacillus GG has been doc
umented in experimental, clinical, and epidemiological studies. The sc
ientific documentation of Lactobacillus GG is reviewed in reference to
uses in functional and clinical foods.