Sleep hygiene is the recommended behavioral and environmental practice that is intended to promote better quality sleep. This recommendation was developed in the late 1970s as a method to help people with mild to moderate insomnia, but, as of 2014, the evidence for effectiveness of individual recommendations is 'limited and inconclusive'. Clinicians assess the sleep hygiene of people who present with insomnia and other conditions, such as depression, and offer recommendations based on the assessment. Sleep hygiene recommendations include establishing a regular sleep schedule, using naps with care, not exercising physically or mentally too close to bedtime, limiting worry, limiting exposure to light in the hours before sleep, getting out of bed if sleep does not come, not using bed for anything but sleep and sex, avoiding alcohol as well as nicotine, caffeine, and other stimulants in the hours before bedtime, and having a peaceful, comfortable and dark sleep environment. Sleep hygiene is the recommended behavioral and environmental practice that is intended to promote better quality sleep. This recommendation was developed in the late 1970s as a method to help people with mild to moderate insomnia, but, as of 2014, the evidence for effectiveness of individual recommendations is 'limited and inconclusive'. Clinicians assess the sleep hygiene of people who present with insomnia and other conditions, such as depression, and offer recommendations based on the assessment. Sleep hygiene recommendations include establishing a regular sleep schedule, using naps with care, not exercising physically or mentally too close to bedtime, limiting worry, limiting exposure to light in the hours before sleep, getting out of bed if sleep does not come, not using bed for anything but sleep and sex, avoiding alcohol as well as nicotine, caffeine, and other stimulants in the hours before bedtime, and having a peaceful, comfortable and dark sleep environment. Assessing sleep hygiene is important to determine whether an individual has inadequate sleep hygiene disorder. The diagnostic assessment is usually conducted using clinical interview and supplemented by self-report questionnaires and sleep diaries, which are typically kept from one to two weeks, to record a representative sample data. There are also computerized assessments such as the Sleep-EVAL system, which can be employed in the diagnostic process. It features 1,543 possible questions automatically selected according to the individual's previous answers. Practice of sleep hygiene and knowledge of sleep hygiene practices can be assessed with measures such as the Sleep Hygiene Index, Sleep Hygiene Awareness and Practice Scale, or the Sleep Hygiene Self-Test. For younger individuals, sleep hygiene can be assessed by the Adolescent Sleep Hygiene Scale or the Children's Sleep Hygiene Scale. Clinicians choose among recommendations for improving sleep quality for each individual and counselling is presented as a form of patient education. One set of recommendations relates to the timing of sleep. For adults, getting less than 7–8 hours of sleep is associated with a number of physical and mental health deficits, and therefore a top sleep hygiene recommendation is allowing enough time for sleep. Clinicians will frequently advise that these hours of sleep are obtained at night instead of through napping, because while naps can be helpful after sleep deprivation, under normal conditions naps may be detrimental to nighttime sleep. Negative effects of napping on sleep and performance have been found to depend on duration and timing, with shorter midday naps being the least disruptive. There is also focus on the importance of awakening around the same time every morning and generally having a regular sleep schedule. Exercise is an activity that can facilitate or inhibit sleep quality; people who exercise experience better quality of sleep than those who do not, but exercising too late in the day can be activating and delay falling asleep. Increasing exposure to bright and natural light during the daytime and avoiding bright light in the hours before bedtime may help promote a sleep-wake schedule aligned with nature's daily light-dark cycle. Activities that reduce physiological arousal and cognitive activity promote falling asleep, so engaging in relaxing activities before bedtime is recommended. Conversely, continuing important work activities or planning shortly before bedtime or once in bed has been shown to delay falling asleep. Similarly, good sleep hygiene involves minimizing time spent thinking about worries or anything emotionally upsetting shortly before bedtime. Trying purposefully to fall asleep may induce frustration that further prevents falling asleep, so in such situations a person may be advised to get out of bed and try something else for a brief amount of time. Generally, for people experiencing difficulties with sleep, spending less time in bed results in deeper and more continuous sleep, so clinicians will frequently recommend eliminating use of the bed for any activities except sleep (or sex). A number of foods and substances have been found to disturb sleep, due to stimulant effects or disruptive digestive demands. Avoiding nicotine, caffeine (including coffee, energy drinks, soft drinks, tea, chocolate, and some pain relievers), and other stimulants in the hours before bedtime is recommended by most sleep hygiene specialists, as these substances activate neurobiological systems that maintain wakefulness. Alcohol near bedtime is frequently discouraged by clinicians, because, although alcohol can induce sleepiness initially, the arousal caused by metabolizing alcohol can disrupt and significantly fragment sleep. Smoking tobacco products before bed is also thought to reduce one's quality of resting by decreasing the time spent in deep sleep, leading to sleep fragmentation and nocturnal restlessness. Both consumption of a large meal just before bedtime, requiring effort to metabolize it all, and hunger have been associated with disrupted sleep; clinicians may recommend eating a light snack before bedtime. Lastly, limiting intake of liquids before bedtime can prevent interruptions due to urinations.