It is better to take a probiotic with one proven strain than it is to take a probiotic with 10 unproven strains.
Taking a probiotic with unproven strains may worsen IBS symptoms. Some bacteria found in the colon can grow out of control and causing problems. For example, some bacteria can be pro-inflammatory (causes inflammation of the bowel) whereas others like Bifidobacterium infantis is an anti-inflammatory probiotic (reduces inflammation of the bowel).
Quoting this research report "Combining potentially anti-inflammatory and proinflammatory bacteria in the same preparation would be particularly counterproductive and presents the alarming situation where an ill-chosen probiotic species might exacerbate disease."
If the strains you are taking have not been proven to be effective how do you know that they are not causing more problems than they are resolving?
-------------------- STABLE: ♂, IBS-D 50+ years - Science of IBS