The nutrient and energy needs of teenagers are higher than those of any other age group and they need to follow a healthy, balanced diet to promote growth and development. Estimated energy requirements vary greatly among males and females because of variations in growth rate, body composition, and physical activity level. Energy requirements are calculated using and adolescent’s gender, age, height, weight and physical activity level, with an additional 25 kcal/day added for energy deposition or growth. Adequacy of energy intake is best assessed by monitoring weight and BMI among adolescents. The energy, protein and fat requirements increase as your child reaches 15 and moves on towards adulthood. On average, boys require about 2800 calories per day, and girls, 2200 calories per day.
When protein intake is inadequate, alterations in growth and development are seen. In the still growing adolescent, insufficient protein intake will result in delayed or stunted increases in height and weight. In the physically mature teenager, inadequate protein intake can result in weight loss, loss of lean body mass, and alterations in body composition. Teenagers who follow vegan diet are at elevated risk for inadequate protein intake. Estimated average requirements for teenagers are from 34 g/day to 52 g/day protein. The densest sources of protein are beef, chicken, turkey, pork, fish, eggs and cheese.
Carbohydrate is the body’s primary source of dietary energy. Teenagers who are very active or are actively growing need additional carbohydrates to maintain adequate energy intake. Most nutritionists recommend that complex carbohydrates make up 50 to 60 percent of a teenager’s caloric intake. Carbohydrate requirements of adolescents are estimated to be 130 g/day an amount that provides enough glucose for proper brain function in virtually all healthy teenagers . Whole grains, fruits, vegetables, legumes are the preferred source of carbohydrates because these foods provide vitamins, minerals and fiber.
Fat supplies energy and assists the body in absorbing the fat-soluble vitamins: A, D, E and K. Dietary fat contains varying proportions of monounsaturated fat, polyunsaturated fat and saturated fat. Foods high in monounsaturated fat, the healthiest kind, include olives and olive oil; peanuts, peanut oil and peanut butter; cashews; walnuts and walnut oils; and canola oil. Corn oil, safflower oil, sunflower oil, soybean oil, cottonseed oil and sesame-seed oil are predominantly polyunsaturated. So are the oils in fish and almonds. 20 percent of daily calories from dietary fat should come equally from the monounsaturated and polyunsaturated fat. Saturated fat is found in meat and dairy products like beef, pork, lamb, butter, cheese, cream, egg yolks, coconut oil and palm oil is the most cholesterol added of the three. Teenagers have to limit their intake of saturated fat to no more than 10 percent of your total daily calories. Nutrition experts recommend that fat make up no more than 30 percent of the diet.
Because of accelerated muscular, skeletal, and endocrine development, calcium needs are greater during puberty and adolescence than during childhood. Bone mass is acquired at much higher rates during puberty – rates of bone accretion during adolescence may be four times as high as rates during early childhood or adulthood. Calcium also plays an important role in muscle contraction, transmitting messages through the nerves, and the release of hormones. If people aren't getting enough calcium in their diet, the body takes calcium from the bones to ensure normal cell function, which can lead to weakened bones.The calcium needs for teenagers are 1300 mg/day. High soft drink consumption in the adolescent population contributes to low calcium intake by displacing milk consumption. Adolescents should increase dairy product, calcium fortified orange juice, bread, dark-green vegetables, nuts and ready to eat cereals intake in their diet.
Red blood cells circulate throughout the body to deliver oxygen to all its cells. Without enough iron tissues and organs won't get the oxygen they need. So it's important for adolescents to get enough iron in their daily diets. Iron needs are highest during periods of active growth among all teenagers and are especially elevated after the onset of menses in adolescent females. Iron requirements are increased during adolescence for the deposition of lean body mass, increase in red blood cell volume. Adolescent boys should be getting 11 milligrams of iron a day and adolescent girls should be getting 15 milligrams. Iron deficiency can affect growth and may lead to learning and behavioral problems. And it can progress to iron-deficiency anemia. Iron-rich foods: red meat, dark poultry, tuna, salmon, eggs, tofu, enriched grains, dried beans and peas, dried fruits, leafy green vegetables, blackstrap molasses and iron-fortified breakfast cereals can make a diet more nutritious.
Zinc is known to be essential for growth and development, immune function, neurological function, and reproduction. Plasma zinc levels decline during pubertal development, retention of zinc increases significantly during the growth spurt. This increased utilization may lead to more efficient use of dietary sources. Zinc deficiency can retard normal growth, impair cognitive development, and delay sexual maturation. Adolescents are at increased risk of zinc deficiency due to the demands of growth. Zinc needs for adolescent boys and girls, aged 14 to 18 years, is 11 mg/day and 9 mg/day. Shellfish, beef, and other red meats are rich sources of zinc, also nuts and legumes are relatively good plant sources of zinc.