Most of the food item produced or manufactured contain some form of yeast, however there some of the food items that contain more yeast then other and disproportion is very drastic. For instance beer as the product have yeast as the primal ingredient, therefore large consumption of beer helps your internal yeast to grow. However there other food items that we consumer regularly on a daily basis that serves as food supply for your internal yeast bacteria to overgrow into yeast infection, this is sugar.
Try to avoid sugar or at least limit the consumption of sugar as much as you can, sugar and all sugar intensive products, like cakes are making a work of your immune system of balancing yeast bacteria presence in your body at the healthy level harder and harder with each and every intake.
Try to avoid all other sugar related food items like refined carbohydrates, artificial sweeteners, melted sugar like the one present in Coke and Pepsi as well as other similar soft drinks and pastries.