Good News About Bad News?

Here’s the good news (sort of). The number of overweight teenagers is not increasing. While the number has tripled since 1980 - yikes - it has plateaued over the past 10 years. Given that news you could say American kids are not getting any fatter. But the bad news is that number of kids ages 2 through 19 carrying too much weight on their frames is nearly 31% (see the graph below.) Almost one in three kids weight too much. From personal observations this is no big surprise. But there is actual proof. In the January 13th issue of the Journal of the American Medical Association, Ogden et al. reported on data collected during 2007-2008 and compared their results to data going back to 1999-2000. Using body mass index (BMI), a common form of assessment for body weight, they found that nearly one third of kids are over weight. 

Granted, BMI only accounts for total weight regardless whether the excess is from fat or muscle. However, look around and tell me how many 2-19 year olds do you see with excess muscle? Not many. The real bad news is that unless these kids begin to exercise and eat less they’ll be likely candidates for heart disease, diabetes, high blood pressure and some types of cancer. But wait. Another study offer a twist

Paturi and colleagues reported in the September, 2009 issue of the Journal of Applied Physiology that overweight rats given to exercise have a more difficult time building muscle. In the chart below, the first two columns show the growth in slow twitch muscle fibers in lean rats (red arrow) and the last two columns so the lack of growth (blue arrow) in obese mice. The reason is found in receptors on the out wall or membrane of the muscle fibers that recognize insulin. Too much body fat weakens the receptors ability to activate the signals inside the muscle that led to muscle growth. Les muscle growth could make exercise less effective towards weight loss. I’ll admit that diet is more important than exercise when it comes to weight loss diet along with exercise is best.  Plus, exercise has its unique set of benefits including strengthening bones and improved mental state.

The same issue of the Journal of Applied Physiology has an editorial entitled, “Sugar tax, save muscle?” Scientific journals are no place for political commentary a point clearly stated by the author who goes on to discuss the implications of the findings from Paturi, et al. I first heard the idea of a sugar tax years ago at an American College of Sports Medicine meeting where it was suggested that the revenue from the tax should be used to off set the higher cost of healthy fruits and vegetables. I didn’t think it was such a bad idea at the time and I still don’t. I’d pay more for a bottle of Dr. Pepper if it meant cheaper oranges and cauliflower. 

Learn more about BMI at Livestrong.com, WebMD.com or many other places on the internet