When the word “suicide” comes to mind, usually it isn’t followed by pictures of blue skies and a bright yellow sun nudged between two puffy white clouds. Instead, and it would only seem logical, to picture dark, hazy skies with a side of thunder and rain. Suicide only happens on insidiously dark days and nights, right? Wrong. Actually, as Swedish researchers have come to discover, suicides may be just as common, if not more so, on long summer days.

It’s in places like Greenland where the sun doesn’t set in the summertime, where many people face insomnia, which can drive a person to suicide.

Constant sunlight harms our circadian rhythm, or our natural biological cycle that occurs day by day. Darkness is the primary cue for signaling the body into sleep, particularly into REM sleep when most of the body’s regeneration and repair takes place. Essentially, our circadian rhythm is the reason we sleep at night and are awake during the day.

Since quantity of sleep is connected to a person’s mental heath, and if a person’s circadian rhythm isn’t allowed to properly function and send the body into necessary deep sleep patterns at around the same time every day, the body becomes increasingly weak and tired. As a result, a person can develop depression through insomnia, and depression can often lead to suicidal thoughts.

At least 877,000 people worldwide kill themselves each year, according to World Health Organization. The U.N. agency estimates that for every suicide death, 10 to 40 attempts are made.

Sleep disturbances have been previously linked to increased suicidal risk in people with psychiatric disorders and adolescents. It is not clear, however, whether this trend is true for the general population.

The Swedish study was conducted in Greenland from 1968 to 2002, and focused on the seasonal variation of suicides. Summer months showed the most suicides.

This effect was most notable in northern Greenland, where the sun remains perched high in the sky from the end of April through the end of August.

One of the researchers said that the suicides were almost exclusively violent and increased during periods of constant sunlight, with 82 percent of the suicides occurring during the daylight months in the northern regions.

Most of the suicides studied involved young men and were violent, such as shooting, hanging and jumping from high places. These types of deaths accounted for 95 percent of all the suicides.

It was speculated by the research team that light-generated imbalances in serotonin – the brain chemical linked to mood – may lead to increased irrationality that when combined with a lack of sleep may drive people to kill themselves.

And all along I thought that paradise was all about lounging under the heat of the sun, watching the tide come in and out, sipping on some iced tea…enjoying the thought of endless summer days.

Maybe I’ll stick closer to the equator for my summer vacation this year and try to enjoy my nightly Z’s just a little bit more.