The ideal amount of sleep in middle and old age has become known

Seven hour – this is ideal amount of sleep due to new research at China's Fudan University.

The ideal night's rest, with insufficient and excessive sleep associated with a reduced ability to pay attention, remember and learn new things, solve problems and make decisions.

Seven hours of slumber was also found to be linked with better mental health, with people experiencing more symptoms of anxiety and depression and worse overall well-being if they reported sleeping for longer or shorter stints.

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