There is no evidence available that directly supports or refutes the relationship between a patient’s intake of probiotics to reduce symptoms and the reduction of symptoms associated with cancer in all cancer patients.

A lack of studies with strong research design [(-) rating in three studies], dissimilar products (each study used different probiotic strains, amounts, dosing), differing patient populations and stage of treatment makes it difficult to provide a straight-forward conclusion on the amount, timing, and type of probiotics needed to prevent/reduce diarrhea as a radiation-related side effect. Probiotics appear to be helpful, but more conclusive research is needed before this can be applied in the clinical setting.