THURSDAY, May 7, 2015 (HealthDay News) -- People who live at higher altitudes are less likely to become overweight or obese, a new study suggests.

The research included more than 9,300 Spanish university graduates who were not overweight or obese at the start of the study. They were divided into three groups based on their homes' altitude: below 407 feet (low); 407 to 1496 feet (medium); and above 1496 feet (high).

Over a median follow-up of 8.5 years, nearly 2,100 of the participants became overweight or obese. After accounting for other factors, such as diet and physical activity, the researchers concluded that study participants who lived at high altitudes were 13 percent less likely to become overweight or obese than those who lived at low altitudes.

However, while the study did find an association between altitude and weight, it wasn't designed to show that living at a certain altitude can actually cause changes in weight.

"While it might not be realistic to expect everyone to move further uphill to reduce obesity levels, it is encouraging to see this effect occurred at only [about 1,500 feet] altitude," the study authors from the University of Navarra in Spain reported.

Previous research has suggested that lower concentrations of oxygen in the air at higher altitudes are associated with lower obesity rates. It's believed that lower concentrations of oxygen in the air may suppress hunger, according to the researchers.

The study was to be presented Thursday at the European Congress on Obesity, in Prague. Findings presented at meetings are generally considered preliminary until published in a peer-reviewed journal.

SOURCE: European Congress on Obesity, news release, May 7, 2015