7 Side Effects of Sitting Too Much That Prove It's Harmful to Your Health


Chances are you've heard by now that sitting is the new smoking. And, even if you lead a generally active lifestyle, you probably spend a great deal of time sitting down. After all, many jobs have us sitting at desks at least eight hours a day, and other daily activities—like driving and watching TV—also contribute to our collectively rising sedentary lifestyle. Of course, you can't necessarily control having a desk job or how long your commute is, but you'd be wise to be more active in your spare time. Need some motivation to invest in a standing desk or get off the couch? From an increased risk of depression to a slower metabolism, here are the side effects of sitting too much that can harm your health.

It can slow down your metabolism.

"The general consensus points to gravity as a key factor in the way food travels through our digestive system," says Niket Sonpal, MD, a New York-based internist and gastroenterologist. Medical experts like Sonpal believe this is the reason why digestion slows down when a person sits after eating rather than walking around.

Unfortunately, sitting too much can impact your metabolism not just after a meal, but all throughout the day. "Sitting all day will leave your calorie burn at its minimum, whereas standing for just an hour will increase your calorie burn by approximately 40 calories depending on weight, sex, and age," Sonpal notes. "Remembering to fit in more steps during your day can increase your calorie burn, help improve digestion and metabolism, and aid in managing your weight."

It makes you more vulnerable to mental health issues.

According to Caesar Djavaherian, MD, co-founder and chief medical officer of Carbon Health, sitting too much can make you more susceptible to mental health disorders—particularly depression. And several studies have found a similar link: In one 2015 meta-analysis published in the British Journal of Sports Medicine, for example, researchers concluded that individuals who engage in the highest levels of sedentary behavior are 25 percent more likely to be depressed than those who only sit occasionally.

It increases your cancer risk.
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Sedentary behaviors have also been linked to an increased risk of certain cancers, as 2014 research published in the Journal of the National Cancer Institute notes. In particular, researchers found that with each two-hour increase in sitting time per day, subjects saw a 10 percent increased risk of endometrial cancer, an 8 percent increased risk of colon cancer, and a 6 percent increased risk of lung cancer.

What's more, among individuals who develop cancer, those with sedentary lifestyles have higher mortality rates. A 2018 study published in the American Journal of Epidemiology found that participants who reported sitting for six or more hours per day were at an 11 percent increased risk of dying from cancer compared to those who sat for less than three hours a day.

And your type 2 diabetes risk.

According to a 2013 study published in the International Journal of Behavioral Nutrition and Physical Activity, the more hours per day an individual spends sitting down, the more likely they are to develop type 2 diabetes. The study, which examined the behaviors of more than 63,000 middle-aged men, found that even with regular exercise, subjects were still at an increased risk of developing the illness if they sat for more than four hours per day. Those who sat for between four and six hours daily saw a 12 percent increased risk of type 2 diabetes, and those who sat for between six to eight hours a day saw a 19 percent increased risk.

It raises your blood pressure.

Sanjiv Patel, MD, a cardiologist at Orange Coast Medical Center in Fountain Valley, California, says that sitting for too long can also lead to higher blood pressure and blood sugar. This is because low energy expenditure causes the body to store energy in the form of fat and leads to an increase in the release of stress hormones.

But if your sedentary lifestyle is making you hypertensive, all you have to do is start moving more. One 2018 study published in the Journal of Occupational and Environmental Medicine found that when sedentary workers took breaks throughout the day, they saw reductions in their blood pressure.

And it increases your risk of cardiovascular disease.

High blood pressure is one of the most critical risk factors for cardiovascular disease, according to a 2015 study published in the journal Medicine (Baltimore). And since sitting too much can lead to hypertension, it can also lead to an increased risk of heart disease.

Research published in 2010 in the journal Medicine & Science in Sports & Exercise found that the sedentary behaviors of riding in a car and watching television were significant predictors of cardiovascular disease (CVD)—and mortality from CVD—in men. But the study also found that, even if participants had high levels of sedentary behaviors, if they also did high levels of physical activity, they had lower rates of death from CVD.

It raises your cholesterol levels.

An August 2015 study published in the journal Lipids in Health and Disease found that subjects who spent more time engaging in sedentary behaviors had higher levels of total cholesterol and LDL cholesterol (also known as the "bad" cholesterol). And, as Patel explains, higher cholesterol levels "lead to metabolic syndrome, which then [increases] the risk of heart attack, stroke, and death from those events." And for more on the dangers of LDL levels, check out 11 Ways You're Putting Yourself at Risk of High Cholesterol.