Your health
Numbers do lie:
The number on the scale might be reassuring, but you can still be too fat. More than half of Americans who are considered normal weight have high levels of body fat, according to a Mayo Clinic study. Women with more than 30 percent body fat and men with more than 20 percent are considered obese, no matter what they weigh.
"The definition of obesity is having excess fat, not excess weight," said cardiologist Dr. Francisco Lopez-Jimenez in this month's issue of Mayo Clinic Women's HealthSource.
What's your body fat? Most health clubs and fitness centers have devices for measuring body composition. If yours is too high, the solution is straightforward, though not easy: Exercise more and eat a healthier diet.
Save your knees
Everyone knows that excess body fat is linked to heart disease and type 2 diabetes, but here's another reason to lighten up: It might save you from hobbling around on painful knees later on.
Almost half of all U.S. adults and nearly two-thirds of obese adults will develop painful osteoarthritis of the knee by age 85, a study based at the University of North Carolina at Chapel Hill suggests. Most at risk are people whose weight was normal at age 18 but who were overweight or obese when they got to be 45 or older.
"Simply put, people who keep their weight within the normal range are much less likely to develop symptomatic knee osteoarthritis as they get older and thus much less likely to face the need for major surgical procedures, such as knee replacement surgery," said Dr. Joanne Jordan, principal investigator of the Johnston County Osteoarthritis Project and senior study author.
The results were published in Arthritis Care & Research.
Asthma risks
Asthma is more common - and severe - in little boys than in girls. But once puberty hits, boys' symptoms often taper off and it's the girls who face the higher risk of severe cases.
Doctors don't really know why this is, but a study in the American Journal of Respiratory and Critical Care Medicine touches on a couple of possible reasons: Female hormones may make women more susceptible, while the male hormone testosterone may have a protective effect. And women have smaller airways in proportion to lung volume than men do.
More research on these gender differences is needed, but in the meantime, boys who start to feel better after being on asthma medication for years - and their parents - can feel comfortable if their doctor suggests tapering off their meds.