Don't Take It Sitting Down: Sitting Harms Your Heart and Health

M.A., Health Writer

It's said that if you snooze, you lose, but if you sit, well, that's not great either. Maybe you admit you're a couch potato or that you lead a sedentary or inactive lifestyle.

Doing so can lead to poor blood circulation, increase inflammation — which is never your friend — and affect your bone health, especially as you age. You don't burn as many calories so you're prone to weight gain. Your muscles get weaker. You're at risk for not only obesity, but for high blood pressure and high cholesterol, heart disease and stroke, as well as type 2 diabetes and certain cancers.

You've seen studies that address health risks of sitting, and some of them "feel like" they contradict each other. What they all say is that sitting too much is bad, and moving more is good. Let's look at four relevant pieces of "the literature" that inform about sitting.

What the science says

This was a big one. A systematic review of six major databases looked at associations of sedentary behavior and physical activity with all-cause mortality — that means death from any cause. If you exercise with moderate intensity for an hour to 1:15 a day, that may eliminate increased risk of death associated with high sitting time, the authors said in 2016 in The Lancet. Certainly, if you do that much exercise, you'd hope to reap that kind of benefit from it.

In December 2017 a study in Circulation reported that if you sit for long periods of time, your heart muscles could be injured due to higher levels of troponins in your blood. These proteins are released when the heart muscle gets damaged, as with a heart attack. The researchers found undesirable troponin levels more closely associated with sitting than with exercise.

Then the American Journal of Epidemiology reported in June 2018 that "prolonged leisure time spent sitting" was associated with all-cause mortality and with 14 of 22 specific causes of death, including heart disease at the top. This was true regardless of how much moderate-to-vigorous intensity physical activity a person did.

But then, from the "in case you missed it" file, evidence that a little really can go a long way —movement, that is. As the authors explained in the American Journal of Physiology/Heart and Circulatory Physiology in July 2016, their study "provides the first evidence that the detrimental vascular effects of sitting are preventable with small amounts of leg movement while seated for an extended period."

Yes, they are talking about fidgeting, so for all the parents whose children are reprimanded in class for exhibiting that behavior, you can remind teachers that it's healthier for them than sitting completely still.

Making sense of sitting

To help sort through it all, HealthCentral reached out for a telephone interview with one of the world's experts on this topic, Professor Stuart Biddle, at the University of Southern Queensland in Australia. He's published more than 250 research papers, 14 books and more on the subject.

"Do people who sit for long periods of time die earlier? Yes, they do," he confirms. "All we need to do is to get people to be more physically active," he says, knowing that is one of the "dreams" healthcare experts have worldwide.

He encourages us to "break up sitting, at least by standing up. Even better, move and move more vigorously. Of course, we know that's not always possible. But that is still the key issue, to get off your seat and do something."

Television watching is worse than just sitting, since it can be associated with consumption of unhealthy snacks and drinks. And as to fidgeting?

"I used to think that was nonsense, but have subsequently changed my view," Professor Biddle says. "Fidgeting is better than nothing, and like standing, is a mild stimulus, which if you do on a regular basis, months and years, could have a substantial effect over a period of time. Real physical exercise, especially high intensity, however, is a much stronger stimulus."

It may seem super-simple, but standing means actually changing posture. "Try to break up sitting as much as possible," he says. "We say 'the best posture is your next posture.' Standing desks are potentially very useful because they allow you to change posture more easily."

He points to an earlier book, Sitting Kills: Moving Heals, by former NASA Director Joan Vernikos, Ph.D. "She draws an analogy between weightlessness in space flight and sitting," he says. Her book encourages developing new lifestyle habits that challenge gravity, such as standing up frequently, stretching, walking and more.

Times have changed

"We're actually fighting our physiology," says Peter T. Katzmarzyk, Ph.D., and associate executive director for population and public health sciences at Pennington Biomedical Research Center. He's widely recognized for his work in the field of physical activity and obesity.

Decades ago, people were more active. "Our level of activity has eroded over time. As humans, we're designed to be efficient and conserve energy, yet our whole society is designed to be more efficient, too," he told HealthCentral in a telephone interview. "For example, we have remote controls and we drive everywhere. That creates an energy imbalance and leads to weight gain and other problems."

If all things are cyclical, even now, planners are thinking about how we can integrate physical activity back into our lives, with options such as walkable communities, he says. "I think we'll be a lot further ahead in 10 years."

Remember the 2008 Physical Activity Guidelines for Americans? "It took 60 years of research to get to that point," Dr. Katzmarzyk says. "It's only been nearly a decade since we started studying sitting. We do know that more time spent sitting puts us at greater risk of developing heart disease and cardiovascular mortality. So yes, we know there is a relationship but we don't really know what to do about it. There's more work to be done."

In the meantime, when you’re sitting down, try to keep movement top of mind, most experts recommend. If you really think about it, you really can find more ways to move more and sit less. Ready? Let's get up and going together!

See more helpful articles:

Just 10 Minutes of Sitting Slows Blood Flow in the Legs

Why Sitting Too Much Is Not Good for You

Are You Sitting Too Much for Your Own Good?