One energy drink per month increases the risk of disturbed sleep, research shows
Energy drinks are linked to insomnia and poor quality sleep, according to a major study that suggests just one can a month increases the risk of disturbed sleep.
Millions of people consume the products, which contain an average caffeine content of 150 mg per liter, as well as sugar, vitamins, minerals and amino acids. They are marketed as mental health and physical performance boosters, and are especially popular among young people.
Although there is already evidence that they reduce sleep quality, it has until now been unclear exactly which aspects of sleep might be more or less affected, and whether there are gender-specific differences in these effects.
A study of more than 53,000 people aged 18 to 35 in Norway has shed new light on the possible negative effects of energy drinks.
Researchers found that those who consumed them every day slept about half an hour less than those who drank them occasionally or not at all.
And the higher the consumption frequency, the fewer hours of nightly sleep are clocked. But even just once – one to three times a month – is linked to an increased risk of disturbed sleep, the researchers found. Their findings were published in the BMJ Open Journal.
Men who drank two or three drinks per week were 35% more likely to go to bed after midnight, 52% more likely to sleep less than six hours and 60% more likely to wake up during the night than those who did not or rarely drunk.
Women were 20% more likely to go to bed after midnight, 58% more likely to sleep less than six hours, and 24% more likely to wake up during the night.
People who consumed the drinks daily generally had more trouble waking up after falling asleep, took longer to fall asleep, and generally slept less than those who didn’t drink them. The study also found that the more people drank, the less sleep they had.
Of women who drank energy drinks daily, 51% reported experiencing insomnia, compared with 33% of women who drank the drinks occasionally or never.
Among men, 37% of daily drinkers suffered from insomnia, compared with 22% of those who rarely or never drank.
Men who were daily drinkers were more than twice as likely to say they slept less than six hours a night than irregular drinkers, while women were 87% more likely.
But even those who drank one to three energy drinks a month had greater sleep problems than those who never touched them, the study suggested.
This was an observational study and as such no firm conclusions can be drawn about the cause. The researchers acknowledged that reverse causality – where energy drink consumption could be a consequence of poor sleep rather than the other way around – could explain the associations found.
Nevertheless, the researchers from the Universities of Bergen and Oslo concluded: “The consumption of ED (energy drinks) was a strong determinant of negative sleep outcomes.
“Even small amounts of ED drugs were associated with poorer sleep outcomes, which warrants more attention to the consequences of ED use among college and university students.”