A commentary on the safety of probiotics.

Probiotics have a long record of safety, which relates primarily to lactobacilli and bifidobacteria. Experience with other forms of probiotic is more limited. There is no such thing as zero risk, particularly in the context of certain forms of host susceptibility. There is poor public understanding of the concept of risk, in general, and risk/benefit analysis, in particular. Uncertainty persists regarding the potential for transfer of antibiotic resistance with probiotics, but the risk seems to be low with currently available probiotic products. As with other forms of therapeutics, the safety of probiotics should be considered on a strain-by-strain basis.