Wednesday, November 4, 2009

More on Obesity

So, there is a new report from some of my colleagues at the Johns Hopkins Bloomberg School of Public Health that suggests that teenagers overweight and obesity issues may not be due to a lack of physical activity.  Once again, detailed in the School's news feed.

The findings suggest that teens may actually be watching less TV rather than more.  It does not mean that they are spending less time in front of some kind of screen (computers and personal digital devices still offer many distractions).  The findings, however, suggest that there have not been huge changes in the amount of physical activity.

So, what does this mean?  Well, if we are assessing the cost-effectiveness of alternative ways of reducing overweight and obesity among teens, this does give us some insight.  While both increasing activity and reducing caloric intake are likely to be bring down weight, the key is that what has changed in recent years may have more to do with caloric intake than with activity.  It is not necessarily easy to change things "back to the way they were" but it may be easier (and require fewer resources) to change things back than to achieve new levels of activity or lower levels of caloric intake.  While I have made some comments in passing that encouraging physical activity may be a cost-effective way to achieve weight control among children, this may not be the case.  Or it is at least likely that efforts to control caloric intake would be more cost-effective.


  1. Not to understate the benefits of increased physical activity (physical and psychological, individual and social), but...
    Reduced caloric intake would seem the no-brainer from an economo-centric point of view. Increased physical activity usually requires an initial investment of time (to which a monetary value can be ascribed) or actual money (for equipment, facilities etc.) in order to derive any subsequent benefit. Reduced caloric intake begins with an action which in-and-of-itself reduces costs (i.e. consuming less food) and leads to a benefit which reduces spending even more (i.e. reduced health care costs in the medium and long term).

  2. I agree with Agathangelos on this one--that the opportunity cost associated with increasing physical activity may be more than simply reducing calories (though both are difficult to enact behavioral changes). I still believe that the cost-effective way when it comes to our childrens' health isn't always the best argument. It doesn't teach our kids to "love their bodies". The whole point of increasing physical activity is in fact to encourage people to take the time to treat exercise as an equally important part of our days. Simply reducing calorie intakes also suggests an unhealthy relationship with food--something which should be enjoyable. Teaching our kids to love their bodies by exercising (which can also reduce anxiety and stress which causes us to overeat) may actually have a higher opportunity cost in the long-run than the short-term costs.