Well, I eat Activia almost every single day for about a year now for no special reasons, just because I like it
Some researchers says that it helps bloated stomach, some say it helps lose weight ... I guess that's just a scam, I haven't seen any difference in my body even if I eat it only because I like it.
If you just bought it because you have some stomach problems, just eat it, it wouldn't hurt you and wouldn't help either.