The best time in life to think about bone health (it's not what you think)
Posted May 19
The skeleton you’ll have in your 60s is the one you built in your teens — a disturbing idea to anyone who’s ever watched a 16-year-old boy eat.
But 80 percent of our bone mass accumulates by 18, and so a teenager's diet, along with other risk factors, can set him up for osteoporosis decades later.
And it’s this debilitating disease — not cancer or strokes — that’s most likely to put women in the hospital in their senior years, often leading to a diminished lifestyle, immobility and even death.
“Most people in nursing homes have fractures. But their death certificates won’t say ‘osteoporosis.’ They’ll say ‘pneumonia’ because they’ve been lying there for a year,” said Lani Simpson, a chiropractor and certified clinical bone densitometrist in Berkeley, California.
A densitometrist, or CCD, is a medical professional trained to interpret bone-density exams. But Simpson’s interest in bone health is more than professional; she was diagnosed with osteoporosis at age 42.
Twenty-five years later, she’s a crusader for bone health, and she’s written a book ("Dr. Lani's No-Nonsense Bone Health Guide") and filmed a PBS special (airing in June) on the subject. While osteoporosis can have multiple causes and is strongly heritable, Simpson says lifestyle changes made now can prevent osteoporosis in later years and slow bone loss even after it’s been diagnosed.
And health professionals believe it’s critically important that families pay attention to bone health lest we become a nation of invalids.
The U.S., already one of the leaders in osteoporosis rates across the world, is poised to grow even more brittle as the baby boomers age, according to the National Osteoporosis Foundation. Ten million Americans have the disease, and 44 million have its precursor, low bone density.
The typical American diet — high in protein, fried foods and sugar — is believed to be one reason for its prevalence in the U.S. Another is the number of sedentary people, who don’t get the exercise they need to build strong bones.
But getting people — and especially teenagers and young adults — to worry about something they can’t see is a challenge. And although our bones begin to lose mass in our 30s, most of us won't know our bones have become dangerously weak until one breaks.
The adult human skeleton has 206 bones, made up of a protein called collagen, embedded with calcium phosphate. Under a microscope, bone looks like a honeycomb, with interlocking caverns. When bone begins to weaken, because of nutritional deficiencies or other factors, the openings widen, and the bone’s ability to support weight declines.
In severe cases of osteoporosis, a bone can snap with only light pressure; Simpson recently treated a woman who broke a bone simply because she took a step.
One in two women and one in four men can expect a fracture due to osteoporosis over their lifetime, according to Susan Randall, senior director for science and education at the National Osteoporosis Foundation in Arlington, Virginia.
For women, the incidence of osteoporosis is greater than heart attack, stroke and breast cancer combined. Their risk is greater than men's because they have less bone mass overall.
“If you’re a woman, and you’re blessed to make it to 90, one in three will have a hip fracture. If you’re a man, and you’re blessed to make it to 90, one in six will have a hip fracture,” said Dr. Kenneth W. Lyles, professor of medicine and director of the Medicine Clinical Research Unit at Duke University School of Medicine in Durham, N.C.
Already, osteoporosis causes 2 million broken bones in the U.S. each year. Because much of the cost is paid by Medicare and Medicaid, this costs taxpayers about $19 billion a year, a number that is expected to rise to $25.3 billion by 2025, when the aging population adds another million fractures to the total.
What remains to be seen is how current health trends affect osteoporosis rates. The millions of recreational runners could help; running and other weight-bearing exercises reduce risk. That's because stressing your bones encourages the development of new bone tissue. (It's also why the bones on your dominant hand and arm are larger and stronger than the other because they're used more.)
But there are other, more troubling indicators, including the prevalence of prescription drugs that negatively affect bone health, as well as nutrient-deficient diets. "The typical American diet is horrible for bones," Simpson said.
And some studies have shown that excess consumption of protein can lead to calcium deficiencies, another cause of low bone density. The U.S. dietary guidelines released in January said that men and boys, in particular, are eating too much protein, and high-protein diets like the Paleo diet remain popular.
About 99 percent of the body's calcium is stored in bones, but bones release calcium to help combat acidity from excessive protein intake or sugary soft drinks.
Some health professionals also worry that a decline in dairy consumption may lead to calcium deficiencies if people don't substitute calcium-rich foods like leafy greens for milk.
Choose your parents wisely
Although diet and exercise play a role in osteoporosis, you can get it even if you work out and eat right.
"The best way to prevent it is to choose your parents and grandparents," Lyles said. "We know that 70 percent of skeletal mass and fracture risk is inherited. If you come from a family that has fractures in their 50s, you have a much greater chance."
African-Americans, Hispanics and Asians have lower rates of osteoporosis than Caucasians for reasons that are not fully understood. Health officials stress, however, that everyone's bones begin to weaken after about age 30, and that no one is immune from the disease.
If you didn't get a chance to choose your parents, there are other steps you can take to preserve bone health. The most common advice is to consume adequate amounts of calcium, along with Vitamin D, which is necessary for calcium absorption.
The necessary amounts vary by individual and age, but Simpson cautions that a day's worth of calcium shouldn't be consumed all at once, but taken in small amounts throughout the day.
Other strategies include:
Lift weights, and perform weight-bearing exercise, such as running, walking or tennis. Teens and young adults, especially, need about an hour of exercise a day, according to the National Institutes of Health.
If you're over 50, get a baseline bone-density test; most insurance plans will cover them if you are 70 or older, or have risk factors such as previous fractures or a family history of osteoporosis.
And, "If you’re going to do just one thing, stop the junk food,” Simpson said.