Isoflavones and Functional Foods Alter the Dominant Intestinal Microbiota in Postmenopausal Women
When I recommend probiotics for patients, there are two things that I mention. First, one of the problems contributing to the need for probiotics is not just the destruction by normal flora, but also the lack of good replacement sources. A 100,000 yrs ago we used to bury our foods in the soil, allowing soil dwelling bacteria like Lactobacillus to completely invade the food.
Personally, I use a fridge–but it does lead to a lack of replacement source of good bacterial flora. Second, once a good balance of healthy flora is set up, good lifestyle habits have to be in place to support their growth.
This article finds that diet can have a positive effect on the balance of bacteria in our gut.