In the U.S., about 92% of Americans own a television and TV watching accounts for more than half of their free time.
Statistics show that the older people get, the more TV they watch. For instance, children between the ages of two and 11 watch an average of 24 hours of television each week. By the time adults reach the age of 65, they average around 48 hours of television-viewing each week, or seven hours daily. Approximately 80% of adults watch an average of three and a half hours of TV daily, and the link between poorer health and TV watching has been well established.
In a new prospective study recently published online in the American Journal of Preventive Medicine, researchers found a link between prolonged TV viewing and an elevated risk of death from many of the major causes of death in the U.S.
For the study, researchers from the National Cancer Institute (NCI) looked at 221,246 adults between the ages of 50 and 71. They were free of chronic disease at the beginning of entry to the study. After an average follow-up of about 14 years, the researchers found a link between daily TV watching, and many of the leading causes of death in the U.S., including heart disease, cancer, diabetes, influenza, pneumonia, Parkinson’s disease, liver disease, chronic obstructive pulmonary disease, and suicide.
People who watch three to four hours of TV each day are 15% more likely to die from these causes of death when compared to people who watch less than an hour of TV per day. People who watch TV for seven or more hours daily increase their likelihood of death by 47%. Furthermore, the risk of death rose at the three- to four-hour mark of daily TV watching during the majority of the cases examined in the study.
“We know that television viewing is the most prevalent leisure-time sedentary behavior and our working hypothesis is that it is an indicator of overall physical inactivity,” said lead study author Dr. Sarah K. Keadle. “In this context, our results fit within a growing body of research indicating that too much sitting can have many different adverse health effects.”
According to the 2008 Physical Activity Guidelines for Americans, published by the U.S. Department of Health and Human Services, adults require at least 150 minutes of moderately intense aerobic activity each week, such as walking, and two days or more of muscle strength training.
However, the study also found that the harmful effects of TV watching impacted inactive and active people, and exercise didn’t totally eliminate the negative effects of long-term TV watching.
“Our study has generated new clues about the role of sedentary behavior and health and we hope that it will spur additional research,” added Dr. Keadle. “Although we found that exercise did not fully eliminate risks associated with prolonged television viewing, certainly for those who want to reduce their sedentary television viewing, exercise should be the first choice to replace that previously inactive time.”
Dr. Keadle cautions that although the associations between TV watching and causes of death have credible biological mechanisms, several of the causes are only just now being reported. As a result, more research is needed to duplicate the study findings.
According to a 2014 study published in the Journal of the American Heart Association,adults may double their risk of premature death when they spend three hours or more every day watching TV.
Sources for Today’s Article:
Keadle, S.K., et al., “Causes of Death Associated With Prolonged TV Viewing,” American Journal of Preventive Medicine, published online July 24, 2015; doi: http://dx.doi.org/10.1016/j.amepre.2015.05.023.
“Prolonged TV viewing linked to eight leading causes of death in US,” ScienceDaily web site, October 27, 2015; http://www.sciencedaily.com/releases/2015/10/151027154939.htm.
“Watching too much TV may increase risk of early death in adults,” American Heart Association web site, June 24, 2014; http://newsroom.heart.org/news/watching-too-much-tv-may-increase-risk-of-early-death-in-adults.
Min Kok, L., “Watching too much television linked to 8 leading causes of deaths in US,” Nationmultimedia.com, October 28, 2015; http://www.nationmultimedia.com/breakingnews/Watching-too-much-television-linked-to-8-leading-c-30271782.html.
“How much physical activity do adults need?” Centers for Disease Control and Prevention web site, last updated June 4, 2015; http://www.cdc.gov/physicalactivity/basics/adults/, last accessed October 28, 2015.