Sitting too long may increase your cancer risk
June 17th, 2014
10:49 AM ET

Sitting too long may increase your cancer risk

If you’re spending a lot of time sitting every day, either in front of the TV or at work, you may be at higher risk for developing certain types of cancer, according to new research published this week in the Journal of the National Cancer Institute.

The study found an additional two hours a day of sedentary behavior was linked to an 8% increase in colon cancer risk, a 10% increase in endometrial cancer risk and a 6% increase in risk for lung cancer. It did not find the same connection for breast, rectum, ovary and prostate cancers or for non-Hodgkin lymphoma.

Researchers came to these conclusions by analyzing 43 existing studies - that included more than 4 million study participants and 68,936 cancer cases - to measure the relationship between hours spent sitting and certain types of cancers.

It’s important to note that while the study identifies a link between sedentary behavior and an increased risk for certain cancers, the research doesn't prove cause and effect.

“Does sitting in front of the TV cause colon cancer? No,” said Dr. Martin Heslin, chief of surgical oncology at the University of Alabama at Birmingham. “But the recommendations (of the study) are awesome.”

Heslin, who was not involved in the research, says that in addition to sedentary behavior, several factors can increase your risk of cancer, including drinking or smoking too much, being obese and having a genetic predisposition.

It’s nearly impossible to say that any one of these factors causes someone to get a specific cancer, he says, but these are the behaviors we can control to help reduce our risk.

“You can affect TV time by turning it off," said Heslin, though he acknowledges it's not so easy to turn off work if you're stuck in an office all day.

In that case, Heslin suggests looking for opportunities to leave your desk, such as standing up while working or taking a walk, to reduce the number of hours you spend sitting down.

“If I ever have the opportunity to design (a meeting room), I’m putting a waist-high table in the room, and no chairs,” Heslin said.

According to an editorial accompanying the study, organizations such as the American Cancer Society and the UK Department of Public Health address the need to reduce hours spent sitting, but do not offer any quantitative recommendations or strategies to help people improve.

Daniela Schmid, one of the study's co-authors and a faculty member in the University of Regensburg's department of epidemiology and preventive medicine, hopes to change that.

"The findings of our study may encourage public health efforts to expand physical activity recommendations to reduce time spent in sedentary behavior,” Schmid said.

Previous studies support the findings in Schmid’s study. A 2012 study conducted by the National Institutes of Health concluded that sitting for several hours a day is bad for you, even if you are physically active. Researchers found even exercising at least 150 minutes each week – the generally accepted public health guideline for physical activity – can’t reverse the negative effects of sitting down for hours.

In that study, sitting increased an individual's risk for major chronic diseases such as Type 2 diabetes, cardiovascular disease, and breast and colon cancers.

soundoff (95 Responses)
  1. Jan

    I'd like to see a study that looked at not only sedentary time but also how much activity was included in the non-sedentary time.

    June 17, 2014 at 11:33 | Report abuse | Reply
    • Yora Nidiot

      I'd like to see a study done showing how many millions of people are being sprayed with toxic cancer-causing chemicals in the air above America from aircraft contrails!! The other day, there 11 of them in a 10 minute time period, all crossing the sky at the same time.. yeah, right, totally normal and non-toxic..

      June 17, 2014 at 22:22 | Report abuse |
    • kotchi

      I'd like to see a study that studies how often pilots are out of their seats on a flight from LAX to Perth Australia...about 20 + hours. Get a real life.

      June 17, 2014 at 22:37 | Report abuse |
  2. PS

    But if I didn't sit so much, I wouldn't have seen this article on how bad it is for me to sit so much.

    June 17, 2014 at 14:02 | Report abuse | Reply
    • Yora Nidiot

      you're my new hero!!!! love the way you think

      June 17, 2014 at 22:20 | Report abuse |
  3. BillHty

    "“If I ever have the opportunity to design (a meeting room), I’m putting a waist-high table in the room, and no chairs,” Heslin said.

    Yeah, and after getting reamed on ADA lawsuits, that's probably the last meeting room you'll design.

    June 17, 2014 at 14:05 | Report abuse | Reply
    • Smash591

      So design the table normal and instead of chairs put exercise balls... there will be no sleeping and your gluts and abs are working the whole time you're attending... yes some will bounce to distract but generally people behave and find that they are more alert and receptive to the presentation/discussion.... Just sayin'

      June 17, 2014 at 14:47 | Report abuse |
    • rbs

      Good reply.

      June 17, 2014 at 22:07 | Report abuse |
    • Nonovyerbeezwax

      My "gluts"?

      June 17, 2014 at 22:08 | Report abuse |
  4. Susannah

    I read this standing up, because I never sit...other than maybe an hour a day to read the newspaper at day's end. All of my computers are positioned for standing.

    There is no way, however, that I would trust (or even tolerate) a physician who uses the word "awesome" in that inaccurate and colloquial and annoying way. ARGH!!!!!!

    June 17, 2014 at 14:49 | Report abuse | Reply
    • ES71

      Well, good for you. Most of us don't have a choice to "position " our work computers or much of anything else.

      June 17, 2014 at 16:02 | Report abuse |
    • Mick

      Excuse me Susannah, but you sound nuts.

      June 17, 2014 at 20:14 | Report abuse |
    • DB

      RE: "There is no way, however, that I would trust (or even tolerate) a physician who uses the word "awesome" in that inaccurate and colloquial and annoying way. ARGH!!!!!!"

      Oh Susannah: Awesome means excellent, amazing, very good, etc. There was nothing wrong with that usage.

      June 17, 2014 at 21:51 | Report abuse |
    • JayCraig

      But then, a new study will come out.. and say that standing too long with lead to increased heart attack and stroke.. due to increased gravity decreasing the venous pressure return from your lower extremities... along with increased pressure in your hip, knee, and ankle joints... causing a decrease in synovial fluid and increasing the chances of hip and knee replacement by your mid to latter 40s by 72%.

      June 17, 2014 at 23:31 | Report abuse |
  5. ES71

    Newsflash – working could increase cancer risk !

    June 17, 2014 at 16:00 | Report abuse | Reply
  6. jzaks

    Hey look, something will get you sooner or later. CNN just wants to let us know that what gets us is just anything we might do or eat or think or believe. You know, just living.

    June 17, 2014 at 16:20 | Report abuse | Reply
  7. jefftotten

    Correlation does not equal causation. People who tend to sit more probably also have other bad habits like eating bad food and not exercising. Those are the real culprits.

    June 17, 2014 at 17:10 | Report abuse | Reply
    • dee bolster

      I agree. I have a sedentary job, but I exercise everyday, including cardio and eat healthy. I think they are just noticing a parallel thing...

      June 17, 2014 at 23:20 | Report abuse |
  8. jasmine


    June 17, 2014 at 17:30 | Report abuse | Reply
  9. LeeMT

    No one thinks sitting all day is good for you. But this research is flawed. Typical with these types of reports, they always, always, use the word "may". This invalidates the whole argument. Besides, do quadriplegics have a higher incidence of cancer? I don't think so.

    June 17, 2014 at 18:55 | Report abuse | Reply
  10. BG

    After reading this I rushed off to a wine tasting, smoked three cigars and haven't sat since.

    June 17, 2014 at 20:04 | Report abuse | Reply
  11. fweioff

    It's much more likely that people who have conditions or other behaviors that can lead to cancer tend to sit a lot, not the other way around.

    June 17, 2014 at 20:46 | Report abuse | Reply
  12. multiversatile

    I'm pretty much screwed. Then again, I figure that spending 20,000 hours of my life exercising vigorously, and another 40,000 hours enduring the pains and discomforts therefrom, might increase my life expectancy by 50,000 hours. That's a net loss of 10,000 hours. I think I'll skip it, do whatever I feel like, and die whenever it happens.

    June 17, 2014 at 20:50 | Report abuse | Reply
  13. IDontKnow

    I personally did a major study and found that only people that are existing without tons of health risks are dead people.

    June 17, 2014 at 20:55 | Report abuse | Reply
  14. Methuselah

    News Flash! Three things cause Cancer
    [1] Worrying about getting cancer
    [2] LIVING
    [3] Listening to doctors who can't get through a day without trying to kill optimism and good health!

    June 17, 2014 at 21:12 | Report abuse | Reply
  15. Pete

    This just in: According to a new study, 100% of humans will eventually die no matter what.

    June 17, 2014 at 21:17 | Report abuse | Reply
    • Edie

      I agree we are all going to die from something..some sooner and some later.

      June 17, 2014 at 22:17 | Report abuse |
  16. Hunt

    Yeah, well, I'm retired, sitting on a bar stool, downing Glenlivet's single malt scotch, ask me if I care.

    June 17, 2014 at 21:26 | Report abuse | Reply
  17. tebowrulz

    What's the result of the next study? "Breathing increases cancer risk" These really are becoming a joke.

    June 17, 2014 at 21:36 | Report abuse | Reply
  18. sol

    Yeah, couch potatoes have a greater cancer risk than people who are active.. makes sense

    June 17, 2014 at 21:40 | Report abuse | Reply
  19. Alex

    CNN...the pre-school of journalism.

    June 17, 2014 at 21:57 | Report abuse | Reply
  20. Sam5

    So I assume if you are in the NBA and spend more time sitting on the bench instead of starting, your cancer risk is higher than say LeBron James getting cancer? If at some point you become a starter, does that negate all the time you spent sitting on the bench? So many questions CNN, so many questions.

    June 17, 2014 at 22:01 | Report abuse | Reply
  21. jackrap

    But it's ok to keep eating fish from the Pacific. Fukushima sushi has been declared safe from Cancer- although your private parts will glow!

    June 17, 2014 at 22:01 | Report abuse | Reply
  22. Roxane

    My mom is 84 years old. Lives in her lazyboy chair. She does not have cancer. Stop writing these articles you yahoos that don't know what you are talking about.

    June 17, 2014 at 22:08 | Report abuse | Reply
    • Eleanor

      This article is about increasing or decreasing risk to cancer. You can't compare Person A to Person B. A person who is not prone to cancer might have an even better chance if they sat less.

      June 18, 2014 at 00:04 | Report abuse |
  23. Beavis

    I'm pretty sure you can find a study where anything you do can be directly related to cancer and/or death.

    June 17, 2014 at 22:09 | Report abuse | Reply
  24. Derek Campbell

    What doesn't cause cancer these days? Breathing air can give you cancer. I say that sarcastically and seriously. Everything that is in the air can probably end up giving you cancer anyway. Everyone move along... nothing to see here besides the fact cancer can be gotten from anything.

    June 17, 2014 at 22:13 | Report abuse | Reply
    • drtodp

      Agreed, just breathing the air will give you cancer and in some places especially the big cities, it will be more prevalent due to massive amounts of carcinogenic brake dust. Don't forget the rubber dust from tires, the exhaust from trucks and cars. Really, have you ever seen a diesel truck spewing out a black smoke? Do you think that is healthy? It is actually nasty hydrocarbon particulate gases (DPM), large molecules.

      June 18, 2014 at 00:46 | Report abuse |
  25. Edie

    My mother was diagnosed with colon cancer in 1970 but i think she had it for at least 2 yrs before the stupid doctor did any tests and she worked as a sales person for 10 yrs at that time. All her other jobs previous to that were standing up too . She was lucky that she survived the cancer and lived to be 85. I don't believe in those stupid studies anyway.

    June 17, 2014 at 22:15 | Report abuse | Reply
  26. Steve Walker

    In a related study, 100% of people who are currently alive are at risk of death at some point in their life times. – I can't believe that I just wasted several moments of my life reading this article while sitting down.

    June 17, 2014 at 22:28 | Report abuse | Reply
  27. Tom

    So what I got out of this story is that the basic functions of life will give you some forms of cancer.

    June 17, 2014 at 22:30 | Report abuse | Reply
  28. columbus

    I heard breathing too much air can cause cancer.

    June 17, 2014 at 22:34 | Report abuse | Reply
  29. mtnDweller

    So, what about all the people who have worked in factories all their lives, standing on a concrete floor for anywhere from 8 – 12 hours a day? Are they at less risk of cancer? I doubt it.

    June 17, 2014 at 22:40 | Report abuse | Reply
  30. bill

    In other news, being born causes cancer...

    June 17, 2014 at 22:45 | Report abuse | Reply
  31. Ubershaman

    As your criticizing the article, just bear in mind there was recently a London School of Economic study that cynicism led to a greater risk of dementia.

    June 17, 2014 at 22:56 | Report abuse | Reply
    • dee bolster

      I read that..I thought they were being sarcastic...:O

      June 17, 2014 at 23:26 | Report abuse |
  32. TheBob

    Ahh f%&k!

    June 17, 2014 at 23:01 | Report abuse | Reply
  33. New Study

    Waking up in the morning has been linked to cancer but not heart disease.

    June 17, 2014 at 23:09 | Report abuse | Reply
  34. Ankur Trivedi

    This is a well written, grammatically correct article. I like how the author emphasizes the importance of the study, while simultaneously telling readers to be cautious of uncompleted research. Most importantly, the article is unbiased, which is rare in today's news (i.e. CNN vs. Fox). Good job, Ms. Parachuru!

    June 17, 2014 at 23:11 | Report abuse | Reply
  35. Peter

    I suppose that cashiers who stand all day long, then shop for their families and clean the home after cooking have no cancers at all?
    Utter nonsense about turning off the TV. This idea that the TV stops you from running is a fallacy. However, too much running can kill you too.

    June 17, 2014 at 23:11 | Report abuse | Reply
  36. cb

    Nature hates sitters.

    June 17, 2014 at 23:17 | Report abuse | Reply
  37. Merry Grant

    This is such a limited study. So limited it does not mean anything.
    Granted we sit to much and I feel confident there are many many more health risk but not cancer. We need to be more mobile in our everyday life.

    June 17, 2014 at 23:31 | Report abuse | Reply
  38. CB

    Warning! Living causes death.

    That's right, in the end, something is going to get you.

    June 17, 2014 at 23:43 | Report abuse | Reply
  39. Jack Handy

    I read this on The Onion.

    June 17, 2014 at 23:45 | Report abuse | Reply
  40. kurtinco

    In other news, breathing too much may increase cancer risk.

    June 18, 2014 at 00:12 | Report abuse | Reply
  41. Ron

    Great, now I'm not allowed to sit..

    June 18, 2014 at 00:15 | Report abuse | Reply
  42. Beep boop

    To all the doctors who think up new things that give you cancer every year.......Shut up ....just Shut up!

    June 18, 2014 at 00:20 | Report abuse | Reply
  43. Pushhyarag2000

    The facility to use intercom to talk to colleagues must be discouraged except in serious emergencies. If people walk to the desk of their colleagues, even during work they will be compelled to move and may walk a few hundred steps every day.

    June 18, 2014 at 00:21 | Report abuse | Reply
  44. gmichael52

    Not only does that make the United States the fattest nation on the planet- it makes them the most cancer prone also.

    June 18, 2014 at 00:34 | Report abuse | Reply
  45. gmichael52

    The United States is not only the fattest, consumes the most resources and now also is the most cancer prone.

    June 18, 2014 at 00:35 | Report abuse | Reply
  46. steve

    oh no.. it isn't all the poison additives in our food or the fact that we ship poutry and pork and seafood to china's filthy factories for processing.. oh no good heavens it isn't the thousands of 'generally accepted as safe' food dyes and things we ingest daily that is giving us cancer. goodness no it is sitting!

    June 18, 2014 at 00:38 | Report abuse | Reply
  47. Gay is wrong

    Being gay increases the risk of cancer.

    June 18, 2014 at 00:53 | Report abuse | Reply
    • Gay is amazing

      Shut the fuuck up.

      June 18, 2014 at 02:10 | Report abuse |
  48. Daniel Ashe

    This article has changed my life. I will by laying down to read and watch TV from now on! THANK YOU CNN!

    June 18, 2014 at 01:00 | Report abuse | Reply
  49. MagnuM

    A breakthrough in scientific research concluded that being alive is a terminal illness.

    June 18, 2014 at 01:28 | Report abuse | Reply
  50. Preston

    Do you know what else increases your risk of cancer? Breathing. Each time you inhale oxygen your chance of coming down with cancer goes up .00001%.

    June 18, 2014 at 01:33 | Report abuse | Reply
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