(1) Bread, rice, noodles and other foods are at the bottom of the food pyramid. The main nutrient in these foods is sugar, which is the main energy source for human life activities.

(2) The type of food that is at the top of the "Balanced Diet Pagoda" and should be eaten less is E oils and fats, which contain more fat. If you eat more, it will cause fat accumulation and lead to obesity.

(3) Protein is an indispensable substance that constitutes human tissue. It is also the main component of various enzymes, antibodies and certain hormones. Adolescents are in a critical period of growth and development and should eat more protein-rich foods. food, such as the food in the third and fourth layers in the table, to ensure growth and development.

(4) Coronary heart disease is caused by coronary atherosclerosis. You should reduce the intake of fats and oils in your diet and eat more vegetables, fruits, etc., that is, eat less fifth-level foods and eat more appropriately. Food on the second floor.

So the answer is: (1) The main nutrient in these foods is sugar, which is the main energy source for human life activities;

(2) Fat; (3) ) protein; three, four; (4) five; two.