With apologies to John Denver, here in the mountains, it’s not just the sunshine on your shoulders that makes you smile. Scientists have been studying the effects of high altitude and mild hypoxemia on dopamine, one of the chemicals in the brain. Dopamine causes feelings of pleasure and happiness. At higher altitudes where oxygen levels in people are lower, dopamine levels are increased.

Here’s a little bit more on how that works: Oxygen makes up 21% of the atmosphere. At sea level, 100% of that oxygen is available to breathe. With a rise in altitude, barometric pressure decreases causing the air molecules to become more spread out. This means that at 10,000 feet above sea level, only 70% of atmospheric oxygen is available to breathe. This results in a state of mild hypoxemia, or lower levels of oxygen in the blood, which in turn causes increased levels of dopamine.

You can read more about dopamine and altitude here:

Toler, A. (2014). “Your brain on altitude.” Catalyst Magazine. Retrieved from http://www.catalystmagazine.net/your-brain-on-altitude-2/

Here’s more about the effects of altitude on oxygenation:

Peacock, A.J. (1998). Oxygen at high altitude. British Medical Journal, 317 (7165). p1063-1066.

Here a calculator to figure out oxygen and barometric pressure at different altitudes:

http://www.altitude.org/air_pressure.php

Submitted by Rebecca Somershoe PNP Student from Vanderbilt University rotating Summer 2016