Seven hours seems to be the ideal amount of sleep that we should aim to get every night – it may even keep us trim. A new study has found that people who slept significantly more or less than the optimum seven hours were overweight or even obese.
It’s not clear if the lack or excess of sleep caused people to put on weight, or if it was obesity that caused the irregular sleeping habit, but Spanish researchers discovered that people were more likely to be overweight if they slept for five hours or less, or for nine hours or more.
(Source: American Journal of Clinical Nutrition, 2008; 87: 310-6).