September 24, 2007–LONDON–Researchers from the University of Warwick, and University College London, have found that lack of sleep can more than double the risk of death from cardiovascular disease. However they have also found that too much sleep can also more than double the risk of death.
According to the research, presented at the British Sleep Society by Professor Francesco Cappuccio from the University of Warwick’s Warwick Medical School, those who had cut their sleeping from seven hours to five hours or less faced a 1.7 fold increased risk in mortality from all causes, and twice the increased risk of death from a cardiovascular problem in particular.
“Fewer hours sleep and greater levels of sleep disturbance have become widespread in industrialized societies,” said Cappuccio. “This change, largely the result of sleep curtailment to create more time for leisure and shift-work, has meant that reports of fatigue, tiredness and excessive daytime sleepiness are more common than a few decades ago. Sleep represents the daily process of physiological restitution and recovery, and lack of sleep has far-reaching effects.”
Curiously, the researchers also found that too much sleep also increased mortality, but predominantly from non-cardiovascular diseases. They found that those individuals who showed an increase in sleep duration to eight hours or more a night were more than twice as likely to die as those who had not changed their habit.
“In terms of prevention, our findings indicate that consistently sleeping around seven hours per night is optimal for health and a sustained reduction may predispose to ill-health.”