Does watching more of television increase risk of coronary heart disease? Well, it could as claimed by a group of scientists at the Medical Research Council (MRC) Epidemiology Unit, University of Cambridge and the University of Hong Kong.
The study published in BAC Medicine show that 11 per cent of cases of coronary heart disease could be prevented if people watched less than an hour of TV each day.
One of the major risk factors for coronary heart disease is sedentary behaviour, which means sitting for long periods of time rather than being physically active. The researchers examined data from the UK Biobank for link between time spent in screen based sedentary behaviours such as TV viewing and leisure time computer use, an individual’s DNA, and their risk of coronary heart disease..
They created polygenic risk scores for each individual – that is their genetic risk of developing coronary heart disease based on 300 genetic variants known to influence their chances of developing the condition. As expected, individuals with higher polygenic risk scores were at greatest risk of developing the condition.
The study showed that people who watched more than four hours of TV per day were at greatest risk of the disease, regardless of their polygenic risk score. People who watched two to three hours of TV a day had a relative six per cent lower rate of developing the condition, while those who watched less than an hour of TV had a relative 16 per cent lower rate.
Leisure time spent using a computer did not appear to influence disease risk
“Limiting the amount of time sat watching TV could be a useful and relatively light touch, lifestyle change that could help individuals with a high genetic pre disposition to coronary heart disease in particular to manage their risk,” said study’s corresponding author Dr Youngwon Kim. He is assistant professor at the University of Hong Kong, and visiting researcher at the MRC Epidemiology Unit.
Last Author Dr Katrien Wijndaele from the MRC Epidemiology Unit, said: “Coronary heart disease is one of the most prominent causes of premature death, so finding ways to help people manage their risk through lifestyle modification is important.”
WORLD HEALTH ORGANIZATION
The World Health Organization recommends reducing the amount of sedentary behaviour and replacing it with physical activity of any intensity as a way of keeping healthier. While it isn’t possible to say for certain that sitting watching TV increases your risk of coronary heart disease, because of various potential confounding factors and measurement error, our work supports the WHO’s guidelines. It suggests a straightforward, measurable way of achieving this goal for the general population as well as individuals at high genetic risk of coronary heart disease.