Know the nutrients that make up a healthy diet to establish your own balanced meals and food preferences.
Proteins, carbohydrates and fats in food serve as the body’s energy sources. Each gram of protein and carbohydrate supplies four Calories, or units of energy, whereas fat contributes more than twice as much: nine Calories per gram.
- About half of our body weight is made up of protein, but most young people in the United States consume twice as much protein as they need.
- Dense sources of protein include beef, chicken, turkey, pork, fish, eggs and cheese.
Carbohydrates, found in starches and sugars, are digested into the body’s main fuel, the simple sugar glucose.
Not all carbs are created equal, however. In planning meals, choose complex-carbohydrate foods and avoid simple carbohydrates.
- Complex carbs provide sustained energy.
- Many starches deliver fiber and assorted nutrients as well.
- They are truly foods of substance: filling yet low in fat.
- Most nutritionists recommend that complex carbohydrates make up 50 to 60 percent 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.
Nutrition experts recommend that fat make up no more than 30 percent of the diet. While Americans have trimmed their fat consumption in recent years, as a nation we’re still about four percent above the suggested level.
Let’s give dietary fat its due. Fat supplies energy and carries fat-soluble vitamins A, D, E and K. But these benefits must be weighed against 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 arteries and eventually cause them to harden.
The danger of atherosclerosis is that the blockage will affect one of the blood vessels leading to the heart or the brain, causing 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 diet.
Three Types Of Fat
Make a habit of reading the “nutrition facts” food labels of processed foods. You may be surprised to see how much fat, not to mention 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.
Dietary fat contains varying proportions of fats, including:
- Monounsaturated fat - the most healthy fat, an unsaturated fat from plant oil:
- olives and olive oil
- peanuts, peanut oil and peanut butter
- walnuts and walnut oils
- canola oil
- Polyunsaturated fat - another unsaturated fat from plant oil:
- corn oil
- safflower oil
- sunflower oil
- soybean oil
- cottonseed oil and sesame-seed oil
- the oils in fish and almonds
- Saturated fat - the least healthy of the three, found in meat and dairy products:
- egg yolks
- coconut oil and palm oil
- Avoid the partially hydrogenated oils in most margarines and vegetable shortenings