Usually infections are a lack of a strong immune system. (look up the value of anti-oxidants). If our bodies are too acidic from too much sugars, meats, simple carbs, then we set ourselves up for sickness. Our bodies want to be alkaline. So our ratio of alkaline in our diet should be higher than our acidic. Do a google search on Alkaline diets and you can find out what type of foods help our bodies. I used to get ear and sinus infections all my growing up years and when I was a teen I read nutrition books and found that my body needed more vitamin A. Vitamin A is important to all mucus membrane organs in the body. If we don't have enough then the mucus membrane will be thin and infection can happen. You have to be careful with Vitamin A because it can cause brain swelling if too much is taken. Usually foods high in vitamin A are green leafy veggies, things like yams and sweet potatoes, fish (cod liver oil), eggs. We are what we eat and if we are full of toxic foods and water then we cannot expect health.
I am an at home mother of 6, 4 grown and married with kids and two teens still at home.