Ignore the scary headlines - sitting is a health concern, but it is NOT the new smoking

ATHABASCA, AB, Sept. 28, 2018 /CNW/ - The stories are almost everywhere — in Time Magazine, the Los Angeles Times and are even promoted by some prominent healthcare institutions — raising the alarm that sitting is just as bad for your health as smoking. But is it really? Not by a long shot.

The evidence says that too much sitting clearly isn't good for you, but smoking remains in a class by itself.

This is the conclusion reached after an investigation led by Athabasca University's Dr. Jeff Vallance and a global team of leading health researchers. The group's findings have just been published in the September issue of the peer-reviewed American Journal of Public Health — and the science doesn't support all those scary headlines.

Vallance, AU Faculty of Health Disciplines Professor and Tier II Canada Research Chair in Health Promotion and Chronic Disease Management, has long been interested in research looking at the health impacts of physical activity and, more recently, too much sitting. He and his team (comprising leading researchers from Australia, Arizona and Alberta) were eager to delve deeper into literature about the latest buzz — the dangers of there being so much sedentary time these days in people's lives — in order to separate fact from fiction.

"The claims have been outrageous and unsubstantiated," Vallance says. "Some have suggested that smoking is safer than sitting. One website that promotes active gaming programs indicated that sitting for six hours is equivalent to smoking 25 cigarettes a day. Another said that sitting for one hour is equivalent to smoking two cigarettes. But these claims are not backed up by any kind of credible science.

"All of these stories communicate a false message and, because many people get a lot of their health information and knowledge from mass media, can have significant health implications.

"We need to communicate the facts as the science tells us, and avoid making erroneous comparisons," Vallance says, explaining the team found that "equating sitting with smoking is unwarranted, misleading and only distorts and trivializes the ongoing and serious risks of smoking."

The researchers arrived at this conclusion through reviewing the science, which necessarily included taking into account the key differences between sitting and smoking when comparing health impacts.

"Smoking has been called one of the greatest public health disasters of the 20th century, and there is good reason for that," Vallance notes, explaining there are several reasons why sitting and smoking can't be compared.

The first is the risk of premature death and chronic disease, both of which are substantially higher for smoking than for sitting (recent studies suggest people who sit a lot have around a 20% higher risk of mortality, and smokers' risk of mortality is almost 300% higher than that of non-smokers).

While people who sit a lot (for example, exceeding eight hours per day) have around a 10-20% increased risk of some cancers and cardiovascular disease, smokers are at more than 10 times (heavy smokers are at more than 20 times) greater risk of lung cancer and have more than double the risk of cancer and cancer mortality.

There are also inherent differences between the two behaviours themselves: smoking is an addiction, while sitting is a habit, driven by convenience and in many cases by there being no other option but to sit.

Nicotine has a profound impact on the development of a fetus, can lead to physiological dependence and can create a spectrum of withdrawal symptoms. No such responses have been linked with sitting.

Furthermore, smoking kills others who are exposed to second-hand smoke (approximately 2.5 million people in the U.S. alone have died from exposure to second-hand smoke-related problems), while the impact of sitting stays with the individual.

The economic impact that smoking and sitting can have on the healthcare system can't be compared, because the relevant data are not available. The annual global cost of smoking-attributable disease was almost US$500 billion in 2012, and there are no estimates for the impact of sitting. Physical inactivity (not meeting physical activity guidelines) cost healthcare systems US$54 billion in 2013.

So what's the take-away from the team's work?

"We know that too much sitting is not good for you," Vallance concludes. "For health, you need to move more, and it is even better if you are active at least at a moderate intensity.

"There is a strong signal emerging from a large body of recent research findings that sitting for excessive amounts of time has adverse effects on a variety of health outcomes, both physiological (higher blood glucose or weight gain) and mental (higher risk of depression).

"But smoking has an impact on nearly every system and organ in the body. The well-established adverse health risks of smoking should not be trivialized or minimized.

"If you have to choose between sitting or having a smoke? I'll still take the couch. Smoking kills…there's no way around it".

Read the full research commentary online at the American Journal of Public Health, ajphapublications.org.

SOURCE Athabasca University Faculty of Business