From Our 2010 Archives
High Altitudes May Aid Weight Loss
Obese Men Lost Weight During Week on Mountain, Study Finds
By Salynn Boyles
Reviewed by Louise Chang, MD
Feb. 4, 2010 -- Looking to jump-start your weight loss? You may want to head to higher ground.
Early research suggests that simply relocating to a higher altitude for a while can help overweight people shed some pounds.
That is exactly what happened when researchers in Germany took 20 middle-aged, obese men to the mountains for a week in a study designed to help explain altitude-related weight loss.
Past research has linked being at very high altitudes with weight loss, but these studies mostly involved hikers and skiers who were highly active.
Because of this, it has been impossible to determine if altitude alone plays a role in weight loss, lead researcher Florian J. Lippl, MD, tells WebMD.
"We wanted to see if being at moderately high altitudes impacted weight when there was no change in activity levels or food availability," he says.
Mountain Living Led to Weight Loss
The men who took part in the study lived in Munich, which is about 1,740 feet above sea level. Their average age was 56, they were all obese (average BMI=34), and they all had risk factors for heart disease and diabetes as a result of being overweight.
They were subjected to a battery of tests while in Munich and again after being relocated to a research station on Germany's highest mountain, the Zugspitze, where they spent a week at an elevation of about 8,700 feet.
During their mountain stay, no restrictions were placed on what the men ate or drank, but their exercise was restricted to slow walks inside the station.
Food intake and activity levels were closely monitored, and follow-up testing was performed a month after the men returned home.
During their alpine week, the men lost an average of 3.5 pounds. Their weight still averaged 2 pounds less than it had at the start of the study a month after their return from the mountain, Lippl says.
The men did eat less and take in fewer calories during their mountain stay, but calorie restriction alone did not explain the weight loss.
They also burned more calories while on the mountain, even though they were no more active than they had been at home.
Exercise Capacity Increased
A month after returning home, the men were still burning slightly more calories than they had at the start of the study, and their exercise capacity had improved dramatically.
Exercise capacity was measured by subjecting the men to a six-minute walking test.
Lippl says the week spent on the mountain appeared to jump-start their metabolisms and make exercise easier for the men.
"We don't really understand why," he says. "Exercising is hard for people who are obese, but something about being at higher altitudes had a lasting impact on exercise capacity in this group."
The researchers hope to duplicate the study at even higher elevations by taking the next group of study participants to a larger mountain in Italy.
University of Southern California physiology professor Richard N. Bergman, PhD, calls the research "preliminary but provocative."
Bergman chairs the department of physiology and biophysics at USC's Keck School of Medicine.
He points out that Colorado has the highest mean elevation of any state in the U.S. and the lowest obesity rate, while states with high rates of obesity also tend to be located at lower elevations.
"Maybe altitude has something to do with this," he tells WebMD. We certainly can't say that from this study, but it is interesting."