Emphasise wholefoods rather than refined and processed foods (for example, whole grains and legumes instead of bread and pasta).
Eat organic foods wherever possible in order to minimise exposure to pesticides and other chemicals and to increase nutrition. Organically grown foods are a lot higher in nutrition than conventionally grown foods.
Eat a primarily plant-based diet that is wide and varied experimenting with different foods to increase nutrition and reduce potential allergies by eating too much of the same foods.
Eat balanced meals and snacks with an adequate intake of protein, complex carbohydrates and good quality fats.