The importance of macronutrients for teens

There are three macronutrients: carbohydrates, protein, and fat.Their nutritional values are very important to teenagers.

Carbohydrates (carbs):
-Carbohydrates are an important source of energy. It may no be as much as the other macronutrients, but it's fast and readily available. One gram of carbohydrates is worth four calories. (Calories are units of energy).
-Some parts of our bodies can't function without carbs, such as out heart, brain, central nervous system, intestines, etc.
-Some carbohydrates contain fiber, which helps prevent major health issues, like obesity or diabetes, down the road.
-According to the USDA, 45%-65% of our calorie consumption should be from carbohydrates.
-Healthy sources of carbs include: starchy food, (like potatoes, bread, and pasta), fruits, and milk.
-Fibers are most often found in vegetables, fruits, and whole grain products.

Protein:
-Protein provides energy if carbs aren't accessible. One gram of protein is worth 4 calories, like carbohydrates.
-It contributes to growth, and people have lots of their growth in the teen years, so not eating enough protein might stunt growth.
-Protein provides lots of enzymes and hormones.
-Protein is a big help towards our immune systems and bid tissues.
-Protein helps to maintain a lean muscle mass.
-Somewhere from 10%-35% of our caloric intake should be from protein.
-Good sources of protein include chicken and other poultry, meat, fish, soy products (like tofu), and beans/legumes.

Fat:
-Fat also provides energy, more than the other macronutrients. Fat is 9 calories per gram.
-The three main types of fat are saturated, unsaturated, and trans. Saturated and trans fat make heart disease more likely, while unsaturated fats make heart disease less likely.
-Fat, like protein, contributes to growth.
-Fat helps to absorb some vitamins, and provides cushioning for various organs.
-Fat maintains cell membranes.
-Fat provides stability to food.
-20%-35% of our calories should be from fat
-Unsaturated fats can be found in foods like olive oil, nuts, avocados, and canola oil.
-Saturated fat can be found in foods like meat, butter, lard and cream.
-Trans fat can be found in baked goods, snack foods, fried food, and margarine.
-While fat has a bad rep for being unhealthy, it is still a necessary part of a diet.

Micronutrients:
Micronutrients are other important things that need inclusion in a diet, although in smaller amounts than macronutrients. Micronutrients include vitamins, such as vitamins, A, C, and D; and minerals, such as iron, zinc, and copper.
Source: http://www.mckinley.illinois.edu/handouts/macronutrients.htm