At least one in four Greeks suffers from insomnia which, when chronic, can provoke mental problems, psychiatrists told a seminar in Athens yesterday. Sometimes mental problems are at the root of insomnia but sleeplessness can also be provoked by health problems or environmental factors – such as the current heat wave – experts from Greece and the USA agreed. Insomnia can be a symptom of latent mental problems, according to Athens University Professor Constantinos Soldatos and Antonis Kalos, professor emeritus at the University of Pennsylvania. If symptoms of sleeplessness persist for a year, the chances of the sufferer developing mental problems increases 40-fold in comparison to people who have no history of problems with sleep, the experts said. According to doctors, the best way of warding off insomnia is to attempt to get at least seven hours sleep a night and to ensure that sleeping and waking times do not vary greatly. Reducing caffeine and alcohol intake also helps.