Televisions entered U.S. households in large numbers after World War II, and personal computers became widespread in business in the 1980s. With these technological innovations, leisure and then work time in the United States began to increasingly center on screen-based systems. Millions of people now spend workdays in front of computers and then retire to their houses to watch TV, play videogames or surf the web.
A 2011 study published in the Journal of the American College of Cardiology, “Screen-Based Entertainment Time, All-Cause Mortality and Cardiovascular Event,” indicates that leisure time spent watching TV or using computers can have significant negative effects, even when balanced with exercise.
The study was conducted by researchers affiliated with University College London, the Baker IDI Heart and Diabetes Institute, the University of Queensland and Edith Cowan University. It involved more than 4,500 individuals who responded to the 2003 Scottish Health Survey, which included assessments of screen time, physical activity and other characteristics. Follow-up contact was made in 2007 to determine subsequent fatal and nonfatal cardiovascular disease events as well as all-cause mortality.
Study results include:
- In the intervening years, 325 subjects died and there were 215 heart attacks or other cardiovascular events.
- Subjects who spent two or more hours of screen-based leisure time a day were twice as likely to have a heart attack or other cardiovascular event.
- Those who had four or more hours of screen-based leisure time per day were 50% more likely to die from any cause.
- 25% of the association between leisure screen time and cardiovascular events was explained by body mass index (BMI), cholesterol levels and other factors.
- Exercise didn’t reduce the elevated risk associated with the high amounts of screen-based leisure time.
Researchers indicated that the increased risk of mortality and cardiovascular events could be partly explained by inflammatory and metabolic factors. While the study focused on recreational screen time, work-based screen time could have similar effects.
Tags: medicine, technology, exercise, obesity, entertainment