The body needs to be nurished if it is to function at optimal capacity. Through my many years of sickness, I have had to learn and relearn how my body respond to food. I had to learn to listen and pay attention which food gave what response. I believe there are some universal laws governing food and nutrition but also that it is individually based, so the most important thing is to pay attention to what works for you. There are many schools of tought on this subject and it is good to explore them and figure out which one speaks to you and then follow it.