Utah is the top state in the US for antidepressant use and has "disproportionately high rates of suicide and associated mood disorders compared to the rest of the country."
Perry Renshaw, a neuroscientist at the University of Utah, thinks the reason could be that living in a high altitude screws up people's neurotransmitters.
Renshaw believes that oxygen-poor air tampers with brain chemistry, leading to a drop in serotonin and an uptick in dopamine. Serotonin and dopamine are neurotransmitters, brain chemicals that relay signals between neurons and other cells.
Serotonin, an inhibitory neurotransmitter, helps stabilize emotions. Antidepressants — SSRIs, (selective serotonin reuptake inhibitor), which include Prozac and Lexapro — work by blocking the transport of serotonin back to the neurons, thereby increasing its supply in the brain.
Dopamine, an excitatory neurotransmitter, plays a vital role in our ability to focus. Too little dopamine can make us scatterbrained, whereas a dopamine increase causes hyper-concentration and feelings of euphoria. Caffeine, prescription drugs, including some ADD/ADHD medications, and illegal stimulants like cocaine and methamphetamine, work by increasing the availability of dopamine in our brains.