THE BONE BANK

By the time teens get through their growth spurts, about 90 percent of adult bone mass is established and after that, no more calcium can be deposited in the body's "bone bank."

Osteoporosis, the brittle bone disease that afflicts 10 million Americans, most of them women older than 50, doesn’t seem like something you need to think about now for your teen. But Michele Reum knows otherwise. Six years ago, her 17-year-old daughter, Brittni, mysteriously began breaking bones, fracturing five over the course of three years: first her right heel, then her right arm three times, then her left knee, then her left arm. Each break occurred when Brittni was just playing on the monkey bars at school and shooting hoops during gym class. As one cast came off, on went another. "Brittni seemed so fragile that I was afraid to let her go outside or play sports," says Reum, a 44-year-old single mother.

Concerned, Brittni’s doctor suggested that she enroll in a bone-density study at Nemours Children’s Clinic in Jacksonville, FL where she was diagnosed with osteoporosis, which is rare in kids and teens. To strengthen Brittni’s bones, a bone doctor there prescribed a calcium supplement and told Brittni to load up on dairy, something she hadn’t consumed much of since being diagnosed with a milk allergy as a baby. Although most kids outgrow the allergy by about age 5, the point at which dairy products are added to their diet, Brittni’s diet stayed dairy-free.

"Brittni never drank milk or ate cheese or yogurt because it just wasn’t something she was used to doing," Reum says. Fortunately, the damage wasn’t permanent. Brittni’s bone density is now normal and she hasn’t broken any bones in two years. "It’s so surprising that all Brittni needed was calcium," Reum says.

Should Your Teen Get A Bone Test?

One of the best ways to get a glimpse of bone health is a bone mineral density (BMD) test that uses dual energy X-ray absorptiometry (DEXA). ?It’s an X-ray of the skeleton to assess the amount of calcium in the bones and gauge their health. But BMD testing isn’t used as a screening tool for healthy?young men or women. “Healthy teens, even those who’ve had multiple fractures, don’t need a BMD test,” says John Mazur, M.D., a pediatric orthopedic-surgeon at Nemours Children’s Clinic in Jacksonville, FL. Possible problems with bone density in these teens can be detected with just a physical exam or by assessing their diet, he says. But your teen may need a BMD test regularly if she has an illness or takes medication for an illness that can impact bone density, such as celiac disease, lupus, rheumatoid arthritis, asthma, diabetes, Crohn’s disease, epilepsy, cerebral palsy, muscular dystrophy, Cushing’s syndrome, kidney disease, leukemia, or cancer.

While her case may sound extreme, Brittni is far from the only teen who needs to be paying attention to bone health. In fact, according to the USDA, 81 percent of teen girls and 48 percent of teen boys fail to get the recommended amounts of calcium—1,300 mgs per day until age 18; 1,000 mgs after that until age 51, when it jumps to 1,200 daily mgs. The shortfall comes at a pivotal time because from age 9-18, hormones, such as estrogen and insulin-like growth factor-1, kick in, prompting the body to store calcium and absorb more of it from food.

"The teen years are when you acquire nearly half of all the bone you’re going to have for the rest of your life," says Susan Coupey, M.D., chief of the division of adolescent medicine at the Children’s Hospital at Montefiore in the Bronx. Your child draws from this "bone bank account" throughout adulthood, especially after age 50, when bone mass naturally starts to decline. If your kid doesn’t build bone now, she may not reach? her peak bone density.

The good news: Research shows that boosting bone density by as little as 5 percent during the teen years lowers the?risk of fractures later by 40 percent. Help your kids maximize their bone-building window of opportunity with our action plan.

Keep dairy handy

A recent study reveals that teens ages 14-18 typically down 18 ounces of soft drinks daily, which is more than double their milk intake. To help your teen boost her calcium quota, encourage her to have at least four 1-cup servings of dairy a day. Stock up on yogurt, yogurt smoothies, low-fat string cheese, and calcium-fortified cereal bars. Besides providing a healthy dose of calcium and vitamin D, dairy products offer a package of nutrients—including riboflavin, phosphorus, potassium, protein, zinc, and essential amino acids—all of which aid bone development.

"Drinking milk fosters good bacteria in the intestine that digests lactose," explains Robert P. Heaney, M.D., professor of medicine at Creighton University in Omaha. When there is not enough “good bacteria," or lactase, to break down lactose, it causes stomach cramps, bloating, gas, and diarrhea.

If your teen is lactose intolerant, there are other options to consider that can ensure a well-balanced, nutritious diet. Older children, including teens, can usually have small amounts of lactose-containing foods, such as yogurt and aged cheeses like Swiss or Parmesan when eaten as part of a meal; lactose-reduced milk is a good option because it retains all the ingredients of regular milk, according to the American Academy of Pediatrics.

Set a good example

Make soft drinks a rare treat for you and your teens. "Don’t bring them into the house," suggests Stephanie Smith, R.D., a spokesperson for the National Dairy Council. That way, your teens won’t be tempted. Also, push nonfat milk at meals, and drink it yourself. It’s important to be a good role model. And try to eat together as often as you can. "Getting calcium into your child’s diet is a family affair," Smith says. In fact, studies show that families who eat together tend to be major milk consumers.

Seek out a supplement

In addition to calcium, teens also need 200 daily IUs of vitamin D, which helps the body utilize the bone-building mineral. Have your teens take a daily supplement as extra health insurance, Dr. Coupey recommends. A multivitamin also offers some other nutrients teens may be missing, such as folic acid.

Give team sports a go

Bones also need regular weight-bearing exercise, such as walking, running, and jumping, to get stronger. Unfortunately, many teens aren’t getting the recommended 60 minutes of daily physical activity their bodies need. But a recent study found that teens who participated in team sports such as soccer, basketball, ultimate Frisbee, baseball, and rugby, had higher bone mass than those who didn’t. Team sports also offer the chance to build bone mass through weight training, a key component of many organized sports programs.

Pay attention to her period

If your daughter hasn’t gotten her first period by age 14, or if she misses her period anytime for three to six months in a row, see a doctor. Delayed puberty and missed periods may be the result of excessive dieting or over-exercising, and can trigger the fall of estrogen levels, compromising peak?bone mass, explains Saralyn Mark, M.D., associate professor of medicine and obstetrician-gynecologist at Yale University and Georgetown University School of Medicine.

Sandra Gordon is a mom of two from Fairfield County, CT, who writes about health, nutrition, parenting, and consumer issues. Find her at sandrajgordon.com.