Boning Up on Bones.
Not For Women Only continued...
As Weaver puts it: "You get more bang for your buck if you
build a strong skeleton when you are young."
Camp Calcium is now in its seventh year, though this past
summer was the first time the camp was run for boys. Funded in part by the
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMSD),
the camp has sought to answer these fundamental questions: How does the body
use calcium to build strong bones? And how much calcium should young people
have in their diet?
At this year's camp, researchers sought to determine the level
of calcium intake that would result in the optimum amount being retained by the
boys' bones. The boys were fed controlled diets that included from 1,800-2,200
milligrams of calcium (approximately six or seven glasses of milk) a day.
By analyzing the urine and feces collections, researchers will
be able to determine how much calcium is being excreted -- as opposed to
absorbed by bones -- at varying levels of dietary intake. Results from the
research will be published early next year.
"We want to see how absorption and retention of calcium
reacts to changes in intake," Martin explains. "Is there a point of
diminishing returns at which drinking more milk is not going to do any
For kids like David Martin, Camp Calcium is a fun and unusual
way to spend a summer. But the findings from research at the camp will likely
affect their lives, and their bones, decades from now.
On the basis of results from Camp Calcium's earlier research
with girls, the National Academy of Sciences' Institute of Medicine revised its
recommendations for the amount of calcium girls should consume from 1,200
milligrams a day to 1,300 milligrams (approximately four to five glasses of
"We have a serious goal of trying to understand the
metabolism of calcium during the adolescent growth spurt," says Joan
McGowan, PhD, chief of the musculoskeletal disease branch at NIAMSD.
"Osteoporosis is not going to be a factor in these kids' lives for half a
century, but among those who do get it, probably 50% will have had inadequate
bone acquisition in adolescence."
McGowan says that when it comes to building bones, it's
adolescence or never. "It's not possible to really build the skeleton after
adolescence, so it's critical to put as much bone in the bank as you can,"
She calls the camp an innovative way to attract kids to
participate in a research project -- always a challenge when the more typical
setting is a hospital or clinic with white-coated researchers. And previous
camps for girls have had the added benefit of introducing young women to
science and to women scientists, she says.