While we all know that obesity is caused by consuming more calories than we expend, studies suggest that our surroundings may also play a factor. Specifically, it has been suggested that people are more likely to be physically active - and therefore, less likely to be overweight or obese - if they live in an environment that we find pleasing. However, few studies have measured the direct effect a pleasing environment can have on activity and obesity levels.

In this survey, researchers analyzed housing and health data collected on approximately 6,900 adults living in eight European cities. Residents in these cities filled out questionnaires on height, weight, and physical activity levels, while trained surveyors assessed the residents' environment, documenting amounts of graffiti and litter, and levels of greenery and vegetation in the immediate area.

People who lived in environments with high amounts of greenery were more than three times as likely to be physically active compared to people living in low-greenery areas; they were also 37 percent less likely to meet the criteria for being overweight or obese. Similarly, people who lived in areas with low graffiti and litter were 42 percent less likely to be overweight or obese, and 47 percent more likely to be physically active, compared to residents of high-graffiti, high-litter neighborhoods.

The results of this study add to the theory that environment can influence a person's willingness or ability to exercise, and thus influence their risk of obesity. As a result, the quality of one's environment also should be taken into account, along with diet and lifestyle, when making an attempt to increase exercise levels and reduce weight.

Ellaway A, Macintyre S, Bonnefoy X. Graffiti, greenery, and obesity in adults: secondary analysis of European cross-sectional survey. British Medical Journal, Sept. 17, 2005;331:611-612.