People failing to exercise may be responsible for as many global deaths as smoking, according to a new study. Individuals not spending at least 150 minutes a week doing moderate exercise (walking for 30 minutes 5 times a week), is causing from approximately 6% to 10% of deaths in four serious non-communicable diseases: coronary heart disease (CHD), type 2 diabetes, and colon and breast cancer worldwide.
In 2008, this lack of exercise was responsible for the deaths of 5.3 million of the 57 million lives that were taken that year globally. This information was revealed in a report in The Lancet, which explained how physical inactivity is much like tobacco smoking or obesity, causing disease and shortening people’s lives.
I-Min Lee, from Brigham and Women’s Hospital and Harvard Medical School, and colleagues, estimated the global impact of physical inactivity on CHD, type 2 diabetes, and colon and breast cancer. They did so by calculating population attributable fractions (PAF) by country and region. PAF means how much of these diseases could possibly be prevented if people started to become as active as they needed to be.
- About 6% of CHD cases are associated with physical inactivity, ranging from 3.2% in southeast Asia to 7.8% in the eastern Mediterranean region
- About 7% of type 2 diabetes cases are linked to lack of activity, ranging from 3.9% to 9.6%
- Around 10% of breast cancer cases (5.6%-14.1%) and colon cancer cases (5.7%-13.8%) are linked to lack of activity
The researchers explain:
“Removal of physical inactivity had the largest effect on colon cancer, and the smallest coronary heart disease, in terms of percentage reduction. However, with respect to the number of cases that can potentially be averted, coronary heart disease would have a far larger effect than would colon cancer because of its higher incidence. Although the worldwide incidence of coronary heart disease is not readily available, deaths from coronary heart disease can be viewed against colorectal cancer deaths to provide some perspective.”
7.25 million people died from CHD in 2008. Lack of physical activity was responsible for 121,000 preventable deaths in Europe, 100,000 in the western Pacific region, 60,000 in the Americas, 59,000 in southeast Asia, 44,000 in the eastern Mediterranean region, and 15,000 in Africa.
There were 647,000 colorectal cancer deaths in 2008. If these people were physically active, 1,000 deaths in Africa could have been prevented, 24,000 in the western Pacific region, 4,000 in southeast Asia, 24,000 in Europe, 2000 in the eastern Mediterranean region, and 14,000 in the Americas.
Although it is in people’s best interest to eliminate physical inactivity from their lives, it is probably unlikely that so many people would change. Bearing this in mind, the research team calculated the possible number of preventable deaths worldwide every year if:
- 10% of people became physically active, 533,000 deaths would be avoided
- 25% of people became physically activeit, 1.3 million deaths would be avoided
If smoking or obesity were eradicated, life expectancy would rise dramatically. Similarly, if physical inactivity no longer existed, the authors say life expectancy of the world’s population would increase by around 0.68 years.
“This summer, we will admire the breathtaking feats of athletes competing in the 2012 Olympic Games. Although only the smallest fraction of the population will attain these heights, the overwhelming majority of us are able to be physically active at every modest levels-e.g. 15-30 min a day of brisk walking- which bring substantial health benefits.”
Written by Sarah Glynn