Sleeping well

Eight hours is usually regarded as a decent night's sleep. However, people differ and this figure does not consider an individual's needs, age, nor the sleep quality.1

Last year, the US National Sleep Foundation set out what it considered the determinants of good sleep quality. Endorsed by several medical societies, the NSF summarised key factors as:2

·       sleeping more time while in bed (at least 85 per cent of the total time);

·       falling asleep in 30 minutes or less;

·       waking up no more than once per night;

·       being awake for 20 minutes or less after initially falling asleep.

Sleeping well is associated with a healthier immune system and better mental health and wellbeing. However, impaired sleep affects mood, judgement and health. In the short term, people can feel irritable or lack focus which may increase the risk of accidents happening; driver tiredness could be a significant factor in a fifth of all road accidents.3,4

Longer-term, sleep quality and quantity influences hormone levels. Insufficient or poor-quality sleep can increase the risk of obesity with decreased leptin levels (the satiety hormone) and excess ghrelin (the hunger hormone). Sleep deprivation increases the risk of cardiovascular disease due to inflammatory modulation being affected, and type 2 diabetes risk is influenced due to decreases in insulin sensitivity and glucose tolerance.5

Poor sleep can also impair libido, and may affect ability to conceive due to decreased levels of fertility hormones.3