ST. LOUIS — Everybody needs a little couch time every now and then. That being said, many Americans are seriously overdoing it when it comes to sitting and lounging around. According to a new study of 51,000 Americans, most sit for prolonged periods of time nearly every day — despite public health messages warning that inactivity increases the risk of diabetes, obesity, heart disease, and even cancer.
The research team, from Washington University School of Medicine in St. Louis, analyzed thousands of surveys taken between 2001 and 2016. These surveys asked respondents about total time spent sitting on a daily basis, and time spent sitting in front of a TV or computer. The researchers made it a point to survey a nationally representative sample of the U.S. population across multiple age groups ranging from children to the elderly.
“In almost none of the groups we analyzed are the numbers going in the right direction,” says epidemiologist Yin Cao, the study’s senior author, in a media release. “We want to raise awareness about this issue on multiple levels — from individuals and families to schools, employers and elected officials.”
Researchers believe that most Americans pick up the tendency to sit for hours at a time during childhood, and end up maintaining the habit well into adulthood.
“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 health-care 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,” comments co-senior author co-senior author Graham A. Colditz.
This study is especially noteworthy because it is the first to actually determine specific numbers on the amount of time Americans of certain age groups spend sitting on a daily basis. Other similar studies have recommended less time spent sitting, but hadn’t actually estimated how much time Americans are spending on the couch.
After crunching all of the numbers, researchers discovered that daily sitting time among both adults and adolescents has steadily increased between 2007 and 2016. Teenagers have gone up from seven hours per day to eight, while adults increased from 5.5 hours to 6.5 hours on a daily basis.
“Until now, we haven’t had data demonstrating the amount of time most Americans spend sitting watching TV or doing other sedentary activities,” Cao says. “Now that we have a baseline — on population level and for different age groups — we can look at trends over time and see whether different interventions or public health initiatives are effective in reducing the time spent sitting and nudging people toward more active behaviors.”
Most Americans spend two hours a day watching TV or videos. A total of 62% of children aged 5-11 spend at least two hours staring at screens every day, and 59% of adolescents aged 12-19 do the same. Additionally, 65% of adults ages 20 to 64 spend at least two hours per day watching TV. In 2015-2016, a whopping 84% of older adults aged 65 or older spent at least two hours per day watching TV as well.
Across all the age groups, 28-38% of respondents spent at least three hours per day watching TV or videos, and 13-23% spent four or more hours in front of a screen. It is also worth noting that males of all ages, non-Hispanic black individuals of all ages, and obese or inactive participants, were all found to be more likely to spend excessive time watching TV or videos compared to other respondents.
Overall screen time outside or work or school has also increased. At least half of the respondents across all age groups reported using a computer during their free time for more than one hour per day in 2015-2016.
The study is published in the Journal of the American Medical Association.