Kid Nutrition: Nutrients to Grow On (cont.)
Teenage girls in particular are among those with the lowest calcium intake relative to their needs. Calcium deficiency is especially dicey during adolescence, when the body forms about half the bone mass it will ever have. Consistently coming up short for calcium during these years is one of the risk factors for bone-thinning osteoporosis decades later. It's even worse for females because of their greater risk for the condition.
How much calcium is enough? According the Institute of Medicine, the group that determines nutrient needs, kids' daily needs for calcium vary by age:
Ayoob says part of the solution to low calcium intake is offering young children and teens calcium-rich beverages and snacks rather than soft drinks, snack chips, and candy. Eight ounces of white or flavored milk, 8 ounces of yogurt, and 1.5 ounces of hard cheese each contain about 300 milligrams of calcium.
While dairy foods are concentrated calcium sources, calcium is also plentiful in plant products, such as fortified orange juice and soy beverages, tofu processed with calcium sulfate, and certain breakfast cereals (check the box label to be sure).
The benefits of making high-calcium foods, particularly dairy, part of your child's daily diet may extend beyond building strong bones. "Emerging research suggests the calcium in dairy foods as part of a balanced diet helps adults achieve and maintain a healthy weight, and the same may be true for children," according to Sheah Rarback, MS, RD, director of nutrition and associate professor at the Mailman Center for Child Development at the University of Miami.
Preliminary evidence shows dairy does work for kids. A Journal of the American Dietetic Association study linked higher calcium intake to lower body fat levels in children aged 2 to 8. Milk and dairy foods were the main sources of calcium in the children's diets in the study.
"Protein is part of every single body tissue," says Rarback, "so that gives you an idea of how important it is to children who are, by their very nature, growing nearly all the time."
Protein provides calories, but its amino acids are what the body really needs. Amino acids are the raw materials for building new cells and tissues and the compounds that direct bodily processes, including enzymes and hormones.
Protein is found in animal and plant foods, with a difference. Animal foods, particularly eggs, supply the amino acids, known as essential amino acids (EAA), that your child's body cannot make. No plant food supplies all of the amino acids, so vegans (those who eat no animal food products) must eat an array of protein-packed plant foods to get the EAA they need. Vegetarians who include dairy foods and eggs typically satisfy EAA needs as long as they eat enough.