Why is milk so important?

Good health starts with good nutrition. Good nutrition can protect against disease later in life. The Food Guide Pyramid and the Dietary Guidelines for Americans, are national recommendations to help people choose diets that promote health and reduce disease risks.

A healthy diet should include food from the major food groups: grains (bread, cereal, rice and pasta); vegetables; fruits; dairy products; meat (poultry, fish, dry beans, eggs and nuts). Fats and oils, located at the top of the food pyramid, should be used sparingly.

Recent studies show that few American children are meeting all of the recommendations outlined in the food pyramid. Teenage girls, on average, failed to meet any of them. One essential nutrient lacking in the diets of many children and teens is calcium, found primarily in dairy products and in dark, leafy green vegetables.

Calcium plays a role in the proper functioning of the heart, muscles and nerves and in maintaining blood flow. But most calcium is used in building bone mass in order to support physical activity throughout life and to reduce the risk of bone fracture, especially that due to osteoporosis, the weakening of bone that can occur late in adulthood.

Though they appear hard, rigid and lifeless, bones are actually growing and alive. Exercise and adequate calcium both influence bone mass. Weight-bearing exercise, such as dancing, weight-lifting, or running, determines bone mass, shape and strength. Smoking, unhealthy eating patterns and alcohol use detract from bone mass. Excessive salt intake may increase the amount of calcium lost in the urine, and therefore, increase the body's need for calcium.

Scientists agree that diets deficient in calcium during childhood and adolescence contribute to the development of osteoporosis, which is not visible until late in life. A positive calcium balance - taking in more than is lost throughout childhood, adolescence and young adulthood - will allow bones to develop to their maximum density.

But it is during the teen years that optimal calcium intake is most important. Bones grow and incorporate calcium most rapidly then. By the age of 17, approximately 90 percent of the adult bone mass will be established.

By the age of 21 or soon after, calcium is no longer added to bones and a few years later, a steady process of loss of calcium from bones begins. Genetically, people differ in how much calcium is in their bones when they reach maturity, but how much calcium they eat while they are growing has an important influence. The more calcium that is in the bones when loss begins, the longer it will take before the bones become fragile and fracture easily.

Research sponsored by the National Institute of Child Health and Human Development (NICHD) has shown that a "window of opportunity" exists to add to the bone bank during the teen years. NICHD researchers have found that supplementing the daily diets of girls, ages 12 to 16, with an extra 350 mg of calcium, produced a 14 percent increase in their bone density, in comparison to unsupplemented girls. If this 14 percent increase in their bone density could be maintained, its impact would be striking.

For every 5 percent increase in bone density, the risk of later bone fracture declines by 40 percent. It is becoming increasingly evident that adequate calcium intake is critical during adolescent years.

The new federal calcium guidelines, the Dietary Reference Intakes, recommend that children ages 4-8 get 800 mg of calcium per day, or the equivalent of 2-3 glasses of low-fat milk. Adolescents and young adults, ages 9-18, whose bones are growing very fast, need more calcium. They should have 1300 mg, or about 4-5 glasses of low-fat milk per day.

Many national health officials believe low-fat milk or low-fat milk products are the best sources of calcium because they contain large amounts of calcium, along with additional nutrients to help the body better absorb calcium. They are also already part of most American diets. Along with calcium, milk provides other essential nutrients, including vitamin D, potassium and magnesium, all essential for optimal bone health and human development. Green leafy vegetables are healthy sources of calcium too, but it takes at

least 5 servings of collards a day to get the same amount of calcium that is in 3-4 glasses of milk.

Children and teens can get enough calcium in their daily diets by drinking 3-4 glasses of milk throughout the day, in breakfast cereal, with lunch, dinner, or as a snack. Making milk the standard and routine drink with meals throughout childhood and adolescence, and even through the adult years, is the best way to assure adequate calcium intake.

For children over the age of two, low-fat or non-fat milk is recommended because it will add calcium to the diet without the fat. There are now a variety of milk products available, ranging from whole milk to non-fat or skim milk, but an 8 oz. glass of any variety still contains about 300 mg of calcium.

Teens and young adults concerned about calorie intake and weight gain should know that 12 oz. Of fat-free milk contains less calories than a 12 oz. soft drink, and provides 1/3 of daily calcium needs as well as many other important nutrients.

Although adequate calcium benefits bones of all ages, children and teens need more calcium today to protect against bone fractures tomorrow.

Reprinted with permission from the National Institute of Child Health and Human Development.

Copyright © 2000-2024 savvyHEALTH.com. All rights reserved.