After the age of 40, avoid coffee if you insist on health and sleep. This is the conclusion of a Canadian study. People who work at night should be especially careful. A study by a group of scientists led by Julie Carrie, a professor of psychology at the University of Montreal, shows that the effect of coffee’s main ingredient, caffeine, on interfering with sleep increases with age.
24 men and women participated in the study – in one group were people between 20 and 30 years, in the other – between 45 and 60. Each had to spend two sleepless nights in a laboratory. One part drank a tablet of 200 milligrams of caffeine three hours before bedtime, the other – a placebo. For all those who consumed caffeine, sleep was affected. Older participants, who slept 50% less, were particularly affected.
“Caffeine is the most commonly used anti-sleep stimulant, but it has detrimental effects on people who work night shifts because they have to sleep during the day, just when their biological clock sends wake-up signals. As we age, sleep is increasingly influenced by coffee, Carrie told Sleep Medicine magazine. She recommends that people over the age of 40 reduce their coffee consumption.