causes of sadness

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You See Peaks Outside Your Window
The higher you are, the lower you may feel (especially if you're 6,500 feet or more above sea level). A University of Utah study found that the high-altitude regions in the U.S. (for instance, Nevada, Utah, Colorado and Montana) and in South Korea had the highest suicide rates. A major cause of unhappiness in mountainous areas is metabolic stress—an effect of mild oxygen shortage (hypoxia)—which worsens the mood for up to 90 days.