Of American adults do not get enough sleep on a regular basis, according to a new study in the Centers for Disease Control and Prevention’s (CDC) Morbidity and Mortality Weekly Report. This is the first study to document estimates of self-reported healthy sleep duration (7 or more hours per day) for all 50 states and the District of Columbia. The American Academy of Sleep Medicine and the Sleep Research Society recommend that adults aged 18–60 years sleep at least 7 hours each night to promote optimal health and well-being. Sleeping less than seven hours per day is associated with an increased risk of developing chronic conditions such as obesity, diabetes, high blood pressure, heart disease, stroke, and frequent mental distress. “As a nation we are not getting enough sleep,” said Wayne Giles, M.D., director of CDC’s Division of Population Health. “Lifestyle changes such as going to bed at the same time each night; rising at the same time each morning; and turning off or removing televisions, computers, mobile devices from the bedroom, can help people get the healthy sleep they need.”

Of British people, are morning risers. Jeffrey Larson, a family therapist at Brigham Young University in Utah, conducted a study with 150 couples. In this group of 300 people, 134 or 44% were morning types, 96 or 32% were evening types and 24% were undifferentiated. As is readily apparent, these few studies have established little consistency in the percentages attributed to each type. Certainly, sample size and composition of the group in question is a factor. In addition, the studies were undertaken with objectives other than providing population information. The determination of types in the group was incidental to the testing of other hypotheses. To this extent, the known scientific studies did not sample a broad range of the general population. It is also important that the same time definitions be used in categorizing night owls, early birds and intermediates. This has not always been the case and may be a reason for some of the inconsistencies in results.

Blue-Collar Workers on the Late Shifts The prevalence of night and evening shift work is greatest among those in service occupations and those who are operators, fabricators, and laborers: Of the over 11 million service workers (which include those in protective services, food service, and cleaning services), 6.5 percent work the night shift and 10.8 percent work the evening shift (U.S. Bureau of Labor Statistics). Of the over 14 million operators, fabricators, and laborers, 7.4 percent work the night shift and 7.7 percent work the evening shift (U.S. Bureau of Labor Statistics). Blue-Collar Workers on the Late Shifts The prevalence of night and evening shift work is greatest among those in service occupations and those who are operators, fabricators, and laborers: Of the over 11 million service workers (which include those in protective services, food service, and cleaning services), 6.5 percent work the night shift and 10.8 percent work the evening shift (U.S. Bureau of Labor Statistics). Of the over 14 million operators, fabricators, and laborers, 7.4 percent work the night shift and 7.7 percent work the evening shift (U.S. Bureau of Labor Statistics).