What we eat is part of our personal environment. We can have a healthier personal environment by making good decisions about diet including what foods to eat, when to eat them, and what quantities to eat. Nutrients in these foods supply the energy and molecules that our bodies need in order to grow, develop, repair damage, and perform the activities of life. The food pyramid guide lists the recommended number of servings we should eat each day.
Food gives us energy. The heat energy in foods can be measured using a calorimeter. The unit of measurement of the heat energy in foods is a calorie.
As members of a food chain we consume food and can transform its energy into mechanical energy during exercise. This is our energy output.
It is important to maintain a balance between our daily energy input and output in order to remain healthy.
Throughout life you must balance your needs as an organism with your personal choices in order to maintain a healthy body. In general, the calories in foods are burned more rapidly by adolescents who have a higher rate of metabolism than by older adults whose metabolic rate is generally slower. Individuals must be aware of these changing needs and change their diets accordingly in order to maintain a healthy personal environment throughout their lifetimes. Healthy eating early in life should become a lifelong habit.