SLEEP How much sleep should older adults get? The National Sleep Foundation (2020) recommends that they get 7 to 8 hours a night. However, 5 percent or more of older adults complain of having difficulty sleeping, which can have detrimental effects on their lives (Farajinia & others, 2014). In an analysis of sleep patterns from 20 to 90 years of age, total sleep decreased about 8 minutes per decade for males and about 10 minutes per decade for females as they got older (Dorffner, Vitr, & Anderer, 2015). Also in this study, as individuals aged, they engaged in more light sleep and less deep sleep. Researchers also have found that older adults' sleep is more easily disrupted than that of younger adults (it takes longer for older adults to fall asleep initially, they wake up more often during the night, and they have greater difficulty going back to sleep) (McRae & others, 2016). Further, the significant reduction in deep sleep in older adults is more likely to occur in men than women (Redline & others, 2004). And in a recent study, older adults who slept 6 hours or less per day were more likely to have fair or poor health (Lauderdale & others, 2016). Page 534 Page 534 developmental connection Language Speech and grammar are highly lateralized functions, strongly depending on activity in the left hemisphere. Connect to Physical Development in Infancy." Sleep factors are linked to many aspects of older adults' lives (Bernstein, DeVito, & Calamia, 2019; Kaur & others, 2020). Poor sleep is a risk factor for falls, obesity, a lower level of cognitive functioning, and earlier death (Kohn & others, 2020; J. H. Liu & others, 2020; Winer & others, 2019). Research indicates that improving older adults' sleep through behavioral and pharmaceutical treatments may enhance their cognitive skills (Dzierzewski, Dautovich, & Ravyts, 2018). Further, one study found poor quality of sleep in individuals with mild cognitive impairment, which in some cases is a precursor for Alzheimer disease (Hita-Yanez, Atienza, & Cantero, 2013). In another study, sleep duration of more than seven hours per night in older adults was linked to longer telomere length, which was similar to the telomere length of middle-aged adults (Cribbet & others, 2014). And one study revealed that even just one night of partial sleep deprivation activated DNA damage characteristic of biological aging (Carroll & others, 2015). However, excessively long sleep duration also is often an indicator of less effective physical and cognitive functioning (Nutakor & Page 535 others, 2020). In a recent study, long sleep duration predicted an increase in all-cause mortality in individuals 65 years and older (Beydoun & others, 2017). Research indicates that older adults who slept 10 or more hours a day were more likely to have cardiovascular disease and diabetes (Han & others, 2016; Yang & others, 2016). And in a recent study, older adults who slept 8 to 10 hours or more a night were more likely to have memory recall problems (Low, Wu, & Spira, 2019). In general, it now appears that when older adults sleep less than 7 hours or more than 9 hours a night, their cognitive functioning is harmed (Lo & others, 2016). Many of the sleep problems of older adults are associated with health problems (Campanini & others, 2019). Strategies to help older adults sleep better at night include avoiding caffeine, avoiding over-the-counter sleep remedies, staying physically active during the day, staying mentally active, and limiting naps (Vanderlinden, Boen, & van Uffelen, 2020). In addition, one study of older adults indicated that walking at or above the internationally recommended level of 150 minutes per week predicted a lower likelihood of problems with sleep onset or sleep maintenance four years later (Hartescu, Morgan, & Stevinson, 2016). And a recent Chinese study revealed that older adults who engaged in a higher level of overall physical activity, leisure-time exercise, and household activity were less likely to have sleep problems (Li & others, 2018). The health profile of emerging and young adults can be improved by reducing the incidence of certain health-impairing lifestyles, such as overeating, and by engaging in health-improving lifestyles that include good eating habits, regular exercise, abstaining from drugs, and getting adequate sleep (Prichard, 2020). For example, a study of college students found that regularly engaging in moderate or vigorous physical activity was linked to adequate daily fruit and vegetable consumption, healthy body mass index, not smoking, being less depressed, having a lower incidence of binge drinking, being less likely to have multiple sex partners, and getting adequate sleep (Dinger, Brittain, & Hutchinson, 2014). And a recent study of college students revealed that regularly eating breakfast was positively linked to their grade point average (GPA), while regularly eating fast food was negatively associated with their GPA (Reuter, Forster, & Brister, 2020). Page 414 Page 414 developmental connection Health Recent research indicates that traditional-age college freshmen go to bed more than one hour later than high school seniors but by their third or fourth years of college, their bedtimes begin to get earlier. Connect to "Physical and Cognitive Development in Early Adulthood." Research indicates that 70 percent of college students do not get adequate sleep and that 50 percent of them report daytime sleepiness (Hershner & Chervin, 2015). In a recent study of college students, sleep deprivation was linked to having a lower grade point average and delayed college graduation (Chen & Chen, 2019). Also, in another recent study of female college students, poorer sleep quality was associated with smartphone dependence and less effective stress management (Wang & others, 2019). Further, in another study, higher consumption of energy drinks was linked to more sleep problems in college students (Faris & others, 2017). The National Sleep Foundation (2019a) recently recommended that 18- to 25-year-olds should get 7 to 9 hours of sleep every night. Many college students occasionally or often pull an all-nighter to cram for an exam. Recent, the National Sleep Foundation (2019b) described why this might not be a good idea and could harm your exam performance: It can distort your memory, cause thinking to be less clear, and impair concentration. Thus, your exam performance will likely be much better if you engage in effective planning and time management and spread your studying over a number of days and weeks. College students are not the only ones who are getting inadequate sleep. Many adults in their late twenties and thirties don't get enough either (Mamun & others, 2020). A statement by the American Academy of Sleep Medicine and Sleep Research Society (Luyster & others, 2012) emphasized that chronic sleep deprivation may contribute to cardiovascular disease and a shortened life span, and also result in cognitive and motor impairment that increases the risk of motor vehicle crashes and work-related accidents. The average American adult gets just under seven hours of sleep a night. How much sleep do adults need to function optimally the next day? An increasing number of experts note that eight hours of sleep or more per night are necessary for optimal performance the next day. These experts argue that many adults have become sleep deprived (Makarem & others, 2019). Work pressures, school pressures, family obligations, and social obligations often lead to long hours of wakefulness and irregular sleep/wake schedules (Haun & Oppenauer, 2019; Riemann, 2019). Professional guidelines for adolescents and emerging adults recommend annual preventive medical visits with screening and guidance for health-related behaviors. One study examined the delivery of preventive health-care services to emerging adults 18 to 26 years of age (Lau & others, 2013). In this study, rates of preventive services utilized by emerging adults were generally low. Females were more likely to receive health care services than males were.