Cheap melatonin pills before bed could help fight childhood depression, a study suggests.
Researchers in Sweden tracked 25,500 children aged six to 18 years who had one pill every evening for about six months.
The risk of self-harm incidents halved in the year after they started taking the pills, compared to the year beforehand.
Researchers suggested that the drop may have been driven by participants getting more sleep, which has mood-boosting benefits. But the study was observational and could not prove the pills were definitely behind the lower self-harm rates.
Popping melatonin pills before bed could help fight childhood depression, a study suggests (stock)
Experts are not encouraging parents to rush out and get melatonin tablets for their children because there are not enough studies showing the benefits.
Melatonin is a hormone crucial to the body’s sleep-wake cycle, with levels rising in the evening as the sun goes down, signaling it is time to go to bed, and dropping to almost nil during the day.
Supplements of the hormone have been available over the counter in the US since the mid-1990s and are available at most pharmacies and health shops for around 12 cents per pill.
More than four million American adults now use the supplements regularly, estimates show, a five-fold uptick on two decades ago.
This is despite some evidence that suggests melatonin can cause cognitive problems when taken over a long period, although this is not definitively proven.
But in Sweden — where the research was carried out — melatonin supplements were not available over the counter until 2020.
For the study, researchers combed through the national database for children aged six to 18 years who had been prescribed melatonin.
Youngsters included in the study had been born between 1989 and 2008.
Among them, the most common disorder was ADHD, affecting 14,000 participants, followed by anxiety and depression, at about 5,500 each.
In the study, each child took a melatonin pill before going to bed for about six months.
Boys were 13 years old on average when they got the prescription, while girls were 15 years old.
It was most common to get the prescription in November and least common over July and August — or the summer holidays.
Researchers then tracked the number of injuries recorded in the group in the year before and the year after starting treatment.
Overall, they recorded a 12 percent decline in injuries.
There were 5,696 in the year before melatonin began compared to 5,011 after, which they said suggested melatonin had helped participants struggling with depression or other conditions.
Poisonings including from drugs and personal care products saw the biggest decline, with levels down 21 percent from 778 to 615 events over the two years. This was driven by girls, among whom the events dropped by 23 percent. It was not clear whether these poisonings were intentional because this was not recorded.
They were followed by falls which fell 15 percent, from 1,970 to 1,669, and body injuries, which fell from 4,585 to 4,056.
Researchers also carried out an analysis of the risk of injuries which showed that the risk of self-harm events — such as poisonings — had halved.
The scientists suggested that melatonin may have helped participants by boosting their mood.
A lack of sleep is known to raise levels of the stress hormone cortisol and disrupt restorative long-wave sleep, both driving someone’s mood into the negative.
It can also make someone more sensitive to pain, by increasing activity in areas of the brain involved in interpreting pain — such as the somatosensory cortex at the top of the brain — while lowering it in those that work to dampen pain perception — like the striatum and insula in the organ’s center.
Research also shows that a lack of sleep among people suffering from ADHD can exacerbate symptoms including impulsive behavior, inattention and hyperactivity.
Dr Sarah Bergen, a psychologist at the Karolinska Institutet who led the research, said: ‘Our findings support the hypothesis that sleep interventions may reduce self-harm in this population, especially in girls.
‘This suggests that melatonin might be responsible for the reduced self-harm rates, but we cannot rule out that the use of other psychiatric medications or psychotherapy may have influenced the findings.’
WHAT IS MELATONIN?
Melatonin is a hormone which controls how asleep or awake people feel.
The hormone is produced in the pineal gland in the brain and its release into the body is controlled by light.
During the day, when the eye absorbs light, melatonin levels in the body are low and, as a result, we feel awake.
But when darkness settles and the amount of light being absorbed by the eye reduces (although this is disrupted in modern societies because of artificial light), more melatonin circulates round the body.
Melatonin prepares the body for sleep by slowing the heart rate, reducing blood pressure, and changing how heat is stored in the body – the body’s core temperature drops while the outside of the body and the limbs become warmer.
The hormone also makes people feel sleepy.
Melatonin supplements can be taken to aid sleep in people who have problems with it, as well as for certain medical conditions such as tinnitus or Alzheimer’s disease.
Sources: Medical News Today and Journal of Applied Physics