What are the three rules of nutrition?

This depends on what your goals are, whether your looking to cut fat or to just eat a healthy diet. If your looking to cut fat you will want to make sure you are supplying your body with the correct amound of calories ,protein and carb ratio. You can find many diet plans online for this. To just stay in shape you will want to eat alot of veggies and fruits as well as healthy meats. Basically just sticking to the food group.