People consuming cans daily sleep half an hour less than those drinking occasionally or never, researchers say

Energy drinks are associated with insomnia and poor-quality sleep, according to a large study that suggests just one can a month raises the risk of disturbed sleep.

Millions consume the products, which contain an average caffeine content of 150mg per litre as well as sugar, vitamins, minerals and amino acids. They are marketed as boosters of mental health and physical performance, and are popular with young people in particular.

While there is already evidence to suggest they reduce sleep quality, until now it has been unclear exactly which aspects of sleep might be more or less affected, or whether there are any sex-specific differences in these effects.

A study involving more than 53,000 people aged between 18 and 35 in Norway has shed fresh light on the potential negative effects of energy drinks.

Researchers found those who consumed them every day slept about half an hour less than those drinking them occasionally or not at all.