Return of rickets in kids

Washington ? Too little milk, sunshine and exercise: It’s an anti-bone trifecta. And for some kids, shockingly, it’s leading to rickets, the soft-bone scourge of the 19th century.

But cases of full-blown rickets are just the red flag: Bone specialists say possibly millions of seemingly healthy children aren’t building as much strong bone as they should – a gap that may leave them more vulnerable to bone-cracking osteoporosis later in life than their grandparents are.

“This potentially is a time-bomb,” says Dr. Laura Tosi, bone health chief at Children’s National Medical Center in Washington.

Now scientists are taking the first steps to track kids’ bone quality and learn just how big a problem the anti-bone trio is causing, thanks to new research that finally shows just what “normal” bone density is for children of different ages.

Dr. Heidi Kalkwarf of the Cincinnati Children’s Hospital led a national study that gave bone scans to 1,500 healthy children ages 6 to 17 to see how bone mass is accumulated. The result, published last summer: The first bone-growth guide, just like height-and-weight charts, for pediatricians treating children at high risk of bone problems.

Almost half of peak bone mass develops during adolescence, and the concern is that missing out on the strongest possible bones in childhood could haunt people decades later. By the 30s, bone is broken down faster than it’s rebuilt. Then it’s a race to maintain bone and avoid the thin bones of osteoporosis in old age.

Building strong bones

Building strong bones takes a combination of calcium, vitamin D and exercise starting in childhood. Here are guidelines on how much youngsters need:

¢ Young children should consume about 800 milligrams of calcium a day. But between ages 9 and 18, when bone growth speeds up, that requirement almost doubles to 1,300 mg. That’s about three cups of fat-free or low-fat milk plus additional calcium-rich foods, such as broccoli, cheese, yogurt, or calcium-fortified orange juice.

¢ Children and adolescents need at least 200 international units of vitamin D. Milk and orange juice often is fortified with the vitamin; a few other foods contain it. Sunlight is a major source. About 10 to 15 minutes of sun exposure weekly is enough for many children, although skin pigmentation alters sun absorption so black children need more. The goal is to get just enough sun for vitamin D production while avoiding too much of its skin-damaging rays. Babies who are breast-fed only and older children at risk for vitamin D deficiency should receive supplements.

¢ Children of all ages need about an hour of physical activity most days, and 10 to 15 minutes at a time can add up. Weight-bearing exercises strengthen bone, anything from team sports like soccer to simply jumping rope or running around. The goal is for the arms or legs to bear all the body’s weight.

¢ The American Academy of Pediatrics recommends that all children be screened for calcium-deficit diets and too little exercise, to identify those whose lifestyles put them at risk for osteoporosis later in life.