How much sleep do you need to be at your best?

Large study reveals seven hours a night - no more or less - is the ideal amount for optimum cognition and mental health

Middle-aged and older people need seven hours of sleep per night for optimal cognitive processing, visual attention, memory and problem-solving, suggests a study using data on almost half a million adults.

The study shows both too much and too little sleep are associated with poorer cognitive performance and mental health,

The researchers from the University of Cambridge in the UK and Fudan University in China examined data from nearly 500,000 adults, aged between 38 and 73, from the UK Biobank.