Dozens of studies point to the importance of sleep in maintaining good health in general and warding off depression, heart disease and diabetes, in particular.
It also appears that getting enough sleep is crucial to weight loss. Researchers from Ohio’s Case Western Reserve University, studying nearly 70,000 middle-aged women, have found that those who slept only five hours a night were 32 per cent more likely to experience significant weight gain (defined as gaining an extra 16.5 kilograms over the 16-year term of the study) and 15 per cent more likely to become obese, compared to those who slept seven hours a night.
Study authors were unable to find any other factor, such as differences in diet, amount eaten or physical activity, which could account for the result, though they suggest that sleeping less may upset a person’s basal metabolic rate (the number of calories you burn while you rest).