I eat Activia everyday. I even get the fiber kind or the prune one. This alone doesn't do anything. Prunes and 100% prune juice doesn't work either. Believe me, some days I take a couple dried prunes + prune juice + 2 fiber gummies + stool softener + activia + those bacteria pills good for your intestine and NOTHING.
Right now, what works for me is Correctol. It clears your intestine in 24h, naturally. I once tried Dulcolax. I was driving and OMG I had to make an emergncy stop. I felt like my bowels were dying and I had an urge to go ASAP. Never again lol.
Wow! I'm so glad I never had to work where y'all have. I dealt with very polite people where I worked and I rarely had to clean the bathroom.
Dairy can plug you up pretty good. My kiddo is lactose intolerant, but she loves her dairy, so on days where she has cheese and milk and yogurt/smoothie, she lives in the bathroom. Are you lactose intolerant? A lot of grains can back you up as well, even if it is whole wheat.
Prunes, coconut water, water, white grape juice, they are all good for constipation. Don't drink apple juice, it can also plug you up.
I know way to much about poop thanks to the kid. Oy!
Okay, time to stop the Activia. If it were going to be beneficial, something would have happened by now.
No eggs, no dairy.
Eat a cup of berries a day. Popcorn has lots of fiber. Lentils too. Raw carrots, celery, and bell peppers. Have at least a half cup of beans every day, or some bean soup. A small to medium apple with the skin as well. Try this for at least a week.
If nothing happens, time to see a GI doc..
And stay away from fiber bars and the like. It's likely that added fiber doesn't give the same benefit as natural fiber, so you aren't getting as much as you think you are.