In the United States, there's a phenomenon of "fat cities" and "thin cities" - cities and regions where obesity is prominent, and those where it's rare. While some cities may be "fat" due to climate, culture or poverty, or "thin" because of a dense, walkable environment, it seems like some "thin cities" may be that way because they're self-selecting for a fit population. Denver and Boulder, for example, which attract thousands of new residents every year, drawn to the ski slopes, trails and "fourteeners" as much as a new job. Nothing is stopping an obese person from moving to Denver, or a thin person from moving to Houston, a city often cited as having a high percentage of obesity. Still, for a fit mountain-climbing, back country-skiing, triathlon-competing type, Denver is far more likely to be on their short list than Houston. If those who are sedentary, a natural environment and climate conducive to outdoors recreation aren't going to be must-haves, and they'll be less likely to seek out a place like Denver. I don't think obese people self-select to Houston because of a thriving restaurant scene and low grocery prices. It's just that the mountains probably don't matter as much to them, and the outdoorsy crowd really isn't flocking there.
The real estate market is changing, with the preferences of Generation X and Y for urban living, compared to more suburban-oriented Baby Boomers. However, all other things being equal -- income, education, age -- are there differences in what people want out of their neighborhoods based on activity levels?
Walkable neighborhoods are certainly healthier than conventional subdivisions, but will those who can benefit from them move there in numbers as great as those who are already active? I'm wondering if traditional neighborhood development will end up like Denver; a self-selected enclave for the thin and active. Communities that are built to be more walkable from the start will be appealing to those for whom walking is important; among them people who are already physically active. For someone who is sedentary, walkability may not be seen as a critical element, and neighborhood form won't be as important. It's not that the sedentary will gravitate to conventional subdivisions, but rather, the more active would stay away from them.
So, just like we have thin cities and fat cities, will the future give us thin neighborhoods and fat neighborhoods, each with their own distinct form? Will a neighborhood designed around TND or NU principles attract the sedentary as much as those who are active?