Deaths By Suicide Increase During Week Of Full Moon, Late Afternoon, Fall Season Are Peak Times: Study

A new study suggests that deaths by suicide increase significantly during the week of a full Moon, and that late afternoons, and the month of September are the peak times for suicides. 

A full Moon in the sky is believed to cause mysterious changes in people. This has been a common perception among people for centuries. Now, a new study suggests that deaths by suicide increase significantly during the week of a full Moon, and that late afternoons, and the month of September are the peak times for suicides. 

The study, led by the Indiana University School of Medicine, was recently published in the journal Discover Mental Health. 

How the study was conducted

Alexander Niculescu from the Indiana University School of Medicine, along with his colleagues, looked at data from the Marion County coroner's office in Indiana about suicides that took place from 2012 to 2016, and found that people over 55 years of age showed a significantly higher increase in deaths by suicide during the week of a full Moon. The researchers found that 3 pm to 4 pm was the peak time for suicides. 

In a statement released by the Indiana University School of Medicine, Niculescu said the team wanted to analyse the hypothesis that suicides are increased during the period around full Moons and determine if high-risk patients should be followed more closely during those times. 

He also said that the team found some important take-home messages in the study, such as the fact that high-risk patients should be followed more closely during the week of the full Moon, during late afternoons and the month of September. 

Earlier, Niculescu and his team had developed blood biomarker tests for mental health conditions such as anxiety, depression and post-traumatic stress disorder, and for pain. The researchers used blood samples previously taken by the coroner from some of the people who died by suicide, and tested the presence of biomarkers in these samples. 

Moonlight affects the genes regulating the body’s circadian rhythms

Niculescu said the team tested a list of top blood biomarkers for suicidality that the researchers identified in previous studies. He explained that the biomarkers for suicidality that are predictive of death by suicide during full Moon, peak hour of the day and peak month of the year compared to outside of those periods appear to be genes that regulate the body's own internal clock, or the circadian clock. 

Niculescu said that using the biomarkers, the researchers found that people with alcohol-use disorder or depression may be at higher risk during the peak time periods.

According to Niculescu, increased light from the full Moon could be responsible for the increase in suicides during that because. This is because ambient light plays an important role in the body's circadian rhythm, which is the natural 24-hour cycle human bodies follow to regulate when a person is asleep and when they are awake. At night, it should be darker, but during a full Moon week, moonlight makes the night bright, and impacts the circadian clock. 

Who is more vulnerable to the effects of moonlight?

Niculescu explained that changes in light can affect vulnerable people, especially those who have other risk factors such as depression, anxiety, alcohol addiction or post-traumatic stress disorder.

Why was 3 to 4 pm the peak time for suicides?

Niculescu said that the peak of suicides from 3 to 4 pm could be linked to stressors throughout the day and a decrease in light beginning to occur that day. This results in a lower expression of circadian clock genes. There could be a decrease in the secretion cortisol, the primary stress hormone. As a result, vulnerable people may become more stressed.

Why is the fall season the peak time for suicides?

In September, many people experience the end of summer vacations, and this could result in stress and seasonal affective disorder effects. This is because daylight decreases during that time of the year. 

Niculescu said the research shows that the full Moon, fall season and late afternoon are temporal windows of increased risk for suicide, particularly in individuals who suffer from depression or alcohol use disorders. 

Niculescu also aims to study if exposure to screens at night contributes to increased suicidality in people, especially the younger generation.