My common sense nutrition principles:
1) Eat real food most of the time. This includes animal protein, naturally-occuring fats,
whole grains, fruits, and vegetables.
2) Eat less highly processed foods, such as refined flour, sugars and vegetable oils.
3) Don't eat too much.
Do this, and I guarantee a healthier you. Nutrition can be complicated, but it doesn't have to be. Make healthy eating a habit, but enjoy the junk food every once in a while.