Calories
A surge in appetite around the age of ten in girls and twelve in boys foreshadows the growth spurt of puberty. How much of a surge? Let's just say that Mom and Dad might want to oil the hinges on the refrigerator door and start stockpiling a small cache of their own favorite snacks underneath the bed.
Calories are the measurement used to express the energy delivered by food. The body demands more calories during early adolescence than at any other time of life.
- Boys require an average of 2,800 calories per day.
- Girls require an average of 2,200 calories per day.
Typically, the ravenous hunger starts to wane once a child has stopped growing, though not always. Kids who are big and tall or who participate in physical activity will still need increased amounts of energy into late adolescence. During middle and late adolescence, girls eat roughly 25% fewer calories per day than boys do; consequently, they are more likely to be deficient in vitamins and minerals.
Nutrients
The nutrients protein, carbohydrates, and fats in food serve as the body's energy sources.
- Each gram of protein and carbohydrate supplies 4 calories, or units of energy.
- Fat contributes more than twice as much: 9 calories per gram.
Protein
Of the three nutrients, we're least concerned about protein. Not because it isn't important—50% of our body weight is made up of protein—but because adolescents in the United States get twice as much protein as they need.
The densest sources of protein include teenage favorites such as:
- Beef
- Chicken
- Turkey
- Pork
- Fish
- Eggs
- Cheese
Carbohydrates
Carbohydrates, found in starches and sugars, get converted into the body's main fuel: the simple sugar glucose. Not all carbs are created equal, however. In planning meals, we want to push complex-carbohydrate foods and go easy on simple carbohydrates. Complex carbs provide sustained energy; that's why you often see marathon runners and other athletes downing big bowls of pasta before competing. As a bonus, many starches deliver fiber and assorted nutrients too. They are truly foods of substance: filling yet low in fat.
- Most nutritionists recommend that complex carbohydrates make up 50% to 60% of a teenager's caloric intake.
- Simple carbs, on the other hand, seduce us with their sweet taste and a brief burst of energy but have little else to offer and should be minimized in the diet.
Dietary Fat
Fat should make up no more than 30% of the diet. Fat supplies energy and assists the body in absorbing the fat-soluble vitamins: A, D, E, and K. But these benefits must be considered next to its many adverse effects on health. A teenager who indulges in a fat-heavy diet is going to put on weight, even if he's active. It would take a workout befitting an Olympic athlete to burn off excess fat calories day after day.
Fatty foods contain cholesterol, a waxy substance that can clog an artery and eventually cause it to harden. The danger of atherosclerosis is that the blockage will affect one of the blood vessels leading to the heart or the brain, setting off a heart attack or a stroke. Although these life-threatening events usually don't strike until later in adult life, the time to start practicing prevention is now, by reducing the amount of fat in your family's diet.
Dietary fat contains varying proportions of three types:
- Monounsaturated fat —the healthiest kind; found in olives and olive oil; peanuts, peanut oil and peanut butter; cashews; walnuts and walnut oil, and canola oil.
- Polyunsaturated fat —found in corn oil, safflower oil, sunflower oil, soybean oil, cottonseed oil, and sesame-seed oil.
- Saturated fat —is the most cholesterol laden of the three; found in meat and dairy products like beef, pork, lamb, butter, cheese, cream, egg yolks, coconut oil, and palm oil.
You want to limit your family's intake of saturated fat to no more than 10% of your total daily calories. The other 20% of daily calories from dietary fat should come equally from the two unsaturated kinds of fat, both of which are contained mainly in plant oils.
If your family eats a lot of packaged and processed foods: Make a habit of reading the food labels. You may be surprised to see how much fat, sugar, and salt (sodium), is in the foods you eat every day. And almost all packaged goods that contain fat are likely to have partially hydrogenated fat, because it has a longer shelf life.
Vitamins and Minerals
A well-rounded diet based on the USDA guidelines should deliver sufficient amounts of all the essential vitamins and minerals. Adolescents tend to most often fall short of their daily quotas of calcium, iron, zinc, and vitamin D.
Unless blood tests and a pediatrician's evaluation reveal a specific deficiency, it's preferable to obtain nutrients from food instead of from dietary supplements.
Additional Information from HealthyChildren.org: