During the Washington budget debate earlier this year, a phrase widely attributed to White House budget director Peter Orszag was rolling off many a reporter’s keyboard: "Health reform is entitlement reform."

Orszag’s idea, in a nutshell, is that controlling the nation’s skyrocketing health care costs, which are fueled in part by the obesity epidemic, would ultimately slow the growth in spending on Medicaid and Medicare, two of the government’s three main entitlement programs.

The House and Senate health care bills include grants to help cities become more walkable, but those funds are in jeopardy. Photo: panuta/Flickr.

What’s happening in the background during Congress’s health care debate this summer can be summed up similarly (with credit to Orszag for the terminology): Transportation reform is health reform.

The link between walkable, bikeable, denser communities and public health is explored in depth by reporter Christopher Steiner, whose new book cites research by University of North Carolina economist Charles Courtemanche that found a causal relationship between the price of gas and U.S. obesity.

For every long-term $1 increase in gas prices, the national obesity rate drops by 10 percent, according to Courtemanche. That relationship goes a long way towards explaining why the House and Senate health care bills include "community transformation" grants to entice cities and towns into building bike paths, playgrounds, and other pedestrian-friendly improvements.

The grants are not assured of surviving the intense health care negotiations now going on in the Capitol, however, because they have become a full-fledged talking point for GOP critics in the House and Senate.

Congressional transportation wonks are focusing much of their energy on the battle over reauthorizing federal transport programs and the climate change bill, but it’s worth noting that they also have a dog in the health care fight.