Findings from a recent study suggest seven hours of sleep per night is the ideal amount in middle to older age.
Poorer cognitive performance and mental health are associated with both too much and too little sleep, according to researchers from Cambridge University and Fudan University in China.
Scientists examined data from nearly 500,000 adults, aged between 38 and 73, from the UK Biobank. Those taking part were asked about their sleeping patterns, mental health and wellbeing. They also completed several cognitive tests.
