A plain yogurt won't have a high enough bacteria count to make a big difference. If you like a yogurt type of probiotic though, there is an awesome one on the market now. It has an extremely high live cell count and is in a liquid form so you don't have to take pills. Its called Pro-Biotic-3 and is available online at http://www.probiotic3.com. I use it every day and its working really well for me. Give it a try and let us know how you make out.