SUNDAY, Feb. 15, 2004 (HealthDayNews) -- Fighting osteoporosis in old age is as simple as drinking four glasses of milk a day -- when you're in your teens.
The bone-thinning disease that strikes the elderly is largely preventable when children and especially adolescents get enough calcium -- 1,200 to 1,300 milligrams daily -- while their bodies are building bone density, doctors say.
The problem is that not enough teens are getting the calcium they need.
"Children and adolescents are not ingesting enough calcium, and will be victims of osteoporosis later in life, especially as people live longer," says Dr. Fima Lifshitz, director of pediatrics and a senior nutritional scientist at the Sansum Medical Research Institute in Santa Barbara, Calif.
As many as 90 percent of teenage girls and almost 70 percent of teenage boys aren't taking enough calcium to ensure strong bones for their adult years, according to the U.S. Department of Agriculture (USDA).
The average teen gets between 700 and 1,000 milligrams of calcium daily, the American Academy of Pediatrics says. Girls, thinking milk is fattening, average only about 740 milligrams a day, health officials report.
An eight-ounce glass of milk contains 300 milligrams of calcium. Other dairy products rich in calcium include cheese and yogurt.
"Dietary habits have changed over time so that children and teens drink more carbonated soda than milk," says Lifshitz, who is on the nutrition council for the American Academy of Pediatrics. That trend, combined with less physical activity, puts teens at long-term risk for osteoporosis.
The USDA reports that milk consumption among teens is down 16 percent since the 1970s while soft drink consumption is up by the same amount. Also, a recent Mayo Clinic study found that from 1977 to 1996, the consumption of soft drinks among girls aged 12 to 19 increased from 207 milligrams to 396 milligrams a day, while milk consumption fell from 303 to 189 milligrams.
Fortunately, these figures aren't going unnoticed by health officials and the government.
For the last several years, the National Institute of Child Health and Human Development (NICHD) has run a national "Milk Matters" campaign to raise awareness of the need for young people to increase their calcium intake. The campaign includes brochures and educational programs as well as conferences for health professionals, and has heightened awareness that calcium consumption and physical activity should be increased for teens.
The NICHD is also funding a multi-center, three-year national study of 1,500 children aged six to 19 to track bone density as it relates to diet, particularly calcium intake; exercise; and development during puberty.
The children will be examined four times over the review period, says one of the study participants, Dr. Mary Horlick, a pediatric endocrinologist at Columbia University's Children's Hospital in New York City.
"Our goal is to understand how bone mass changes and to be able to track growth curves for bone density the way we do now with height and weight," she says.
This information will help doctors assess which children might need medical help to boost their bone density, she says.
The American Academy of Pediatrics has also addressed the problem of poor calcium intake. Several years ago, it issued a policy statement for member doctors with guidelines for adequate calcium intake. The statement also included studies reporting increases in bone fractures in children and teens with low calcium intake.
The results of all this attention have started to pay some dividends.
"Kids are beginning to increase calcium consumption a little bit more, and we're optimistic because health professionals continue to rally around this issue," says Gregory Miller, senior vice president of nutrition communications for the National Dairy Council.
The role of exercise in increasing bone density is being studied, too.
A study in the December 2003 issue of Pediatrics found bone mineral density increased by 5 percent among 191 middle school girls who participated in weight-bearing exercise such as jumping rope three times a week for about 10 minutes over a two-year period.
While calcium and vitamin D intake are important for building bone density, Horlick says, exercise seems to play a role as well.
"Weight-bearing exercises seem to be very important, particularly for the hips," she says.
Lifshitz recommends that children, adolescents and their parents follow some simple guidelines to promote strong bones while young.
"Kids should eat a healthful diet with the recommended calcium -- stay away from empty calories from fruit drinks. They should be active -- the human body isn't meant to be watching TV all day long. And number three, they should get outside to get vitamin D, which helps absorb the calcium."
An estimated 10 million Americans -- 80 percent of them women -- have osteoporosis, and almost 34 million more are estimated to have low bone mass, placing them at increased risk for the disease.
Check with the National Institute of Child Health and Human Development for more about the "Milk Matters" program. To learn more about osteoporosis, visit the National Osteoporosis Foundation.