I just read two amazing new studies about probiotics and immune function. Both studies showed that probiotic combinations are ineffective in improving immune function. In the studies, only single strains showed positive effects.
Ever since becoming ill with CFIDS six years ago, I have taken a probiotic combination pill every day - so have my sons. In fact, I pay a lot of money for an expensive, refrigerated brand that contains 10 different varieties of probiotic; I assumed more was better. I never noticed any significant difference in how I felt, but it was one of those things that I kept up because of all the research showing that probiotics help immune function and GI problems. Now I discover I may have been wasting my money all these years!
The first study summary shows that single strains were more effective than combination pills. The second study tested which single strains were most effective in improving immune function, in addition to showing that the combinations had no effect at all. The theory is that the different bacteria may cancel each other out.
No more expensive multi-probiotics for me! I plan to switch to a single strain brand right away. My sons' pediatrician has told me before that the brand Culterelle had more active bacteria in it than other brands in laboratory tests, so maybe we'll try that. It's not the strain that scored best in the immune system tests, though, so I may try to hunt down the ones mentioned in the second study.