No matter how many ongoing warnings over the past decades, Americans are not heeding them at great peril to the health of individuals, communities, and the nation as a whole. Obesity and the results of a sedentary lifestyle are a national security level issue at this point.
Recent research from Washington University School of Medicine and colleagues highlights that most people are living a dangerously sedentary lifestyle as they sit for prolonged periods of time—leading to obesity, diabetes, heart disease, and certain cancers.
The research team analyzed surveys (National Health and Nutrition Examination Survey) from 51,000 people from 2001 to 2016 to track sitting trends in front of TVs and computers and the total amount of time spent on a daily basis. This research is the first to document sitting in a nationally representative sample of the U.S. population across multiple age groups—from children to the elderly—as well as different racial and ethnic groups. The study results were published in the Journal of the American Medical Association.
The survey participants included four age groups: children ages 5 to 11, adolescents ages 12 to 19, adults ages 20 to 64, and adults ages 56 and older. Race and ethnicity were defined as non-Hispanic white, non-Hispanic black, Hispanic, and other races, including multiracial.
The Results (Summary)
The team found that Americans spend at least two hours per day sitting and watching TV and videos. Among children ages 5-11, 62% spent at least that long in front of screens daily. For adolescents ages the number was 59%. About 65% of adults spent at least two hours watching TV per day while 84% of adults 65 and older spent at least that much time watching TV.
Adolescents and adults sit more and more—just over 8 hours per day for teenagers and 6.5 hours for adults.
Computer screen time continues to increase as more than half of individuals across all age groups use a computer during leisure time for more than one hour per day. Up to 25% of the American population used computers outside of work and school for three hours or more.
Yin Cao, ScD, an epidemiologist and assistant professor of surgery in the Division of Public Health Sciences notes, “In almost none of the groups we analyzed are the numbers going in the right direction.” She continued, “We want to raise the awareness about this issue on multiple levels—from individuals to families to schools, employers and elected officials.”
Graham A. Colditz, MD, DrPH, the Niess-Gain Professor of Surgery and Director of the Division of Public Health Sciences commented “We think a lot of these sedentary habits are formed early, so if we can make changes that help children be more active, it could pay off in the future, both for children as they grow to adulthood and for future healthcare spending. Sedentary behavior is linked to poor health in many areas, and if we can reduce that across the board it could have a big impact.”
Yin Cao, ScD, an epidemiologist and assistant professor of surgery in the Division of Public Health Sciences
Graham A. Colditz, MD, DrPH, the Niess-Gain Professor of Surgery and Director of the Division of Public Health Sciences
Chao Cao, a recent graduate of the Brown School and a data analyst in Yin Cao’s lab, co-led the analyses. Washington University also collaborated with researchers at a number of other institutions, including Charles Matthews, PhD, at the National Cancer Institute (NCI); Lin Yang, PhD, at the Alberta Health Services, Calgary, Canada; the Harvard T.H. Chan School of Public Health; Memorial Sloan Kettering Cancer Center; and Massachusetts General Hospital and Harvard Medical School.