The problem with Culturelle is that it is one strain of probiotic, Lactobacillus. It's better to have multiple strains. Our guts are composed on many, many different bacteria, all serving different purposes.

Kefir is great, but watch the sugar content. If you can, buy it plain and add your own stevia to it.

Also, you can try fermented foods like kimchee or even Kombucha, provided it's not pasteurized. Those have lots of probiotics, and at the moment, I'm making my own kombucha scoby in my closet....

Good luck!