A new study from the University of Regensburg in Germany found that people who spend most of their time sitting down have an increased risk for numerous cancers, including colon cancer. Previous studies have also linked sitting to health problems such as heart disease, high blood sugar, blood clots, and obesity.
The study looked at the results of 43 studies that examined the link between sitting and 70,000 cases of cancer. This type of meta-analysis helps reveal the trends across numerous research studies, helping researchers to base a conclusion on large amounts of data. In this case, the results were remarkably consistent across numerous studies, making the association between sitting and colon cancer well worth noticing.
Colon cancer and endometrial cancer were both linked to spending most of the time sitting down. However, not all cancers were linked to a sedentary lifestyle – there was no increased risk of testicular, prostate, breast, ovarian, stomach, esophagus, or kidney cancer.
The Results
Just how dramatic are the risks? People who spent the most time sitting, such as people who worked desk jobs or driving jobs, had a 24% increased risk of developing colon cancer as compared to the group that spent the least amount of time sitting. Every two-hour increase in sitting time was associated with an 8% increased risk of colon cancer.
Consumption of television is closely linked to both a sedentary lifestyle and to the consumption of junk food and high-calorie drinks. Researchers found an even more dramatic risk of colon cancer for people who spent the most time watching television, with a 54% increased risk as compared to those who watched the least amount of television.
Even people who regularly hit the gym but spend most of their day sitting were at an elevated risk of colon cancer, a fact which suggests that regular exercise doesn’t offset all the risks of excessive sitting.
Several factors may be at play in this link. High blood sugar and high insulin are heavily associated with colon cancer. Meanwhile, past studies have shown that getting up after meals lowers blood sugar and walking lowers insulin levels.
How to Address the Risks
If you work a desk job or other job that requires long periods of sitting, there may be no way for you to start spending most of your time on your feet. However, people with desk jobs may be able to minimize their risks by taking small steps to get more active. During the day, you can get up regularly – even just getting up every hour to stretch and take a walk to the copy machine could help.
In your free time, minimizing the amount of time spent watching TV and maximizing the amount of time you spend on your feet in more active pursuits is valuable. Exercise can help, as can incorporating more active hobbies into your lifestyle – for example, maybe a short post-dinner walk can replace a post-dinner TV session.
People over 50 and other people with an increased risk of colon cancer should be screened periodically. In addition, you should visit a colon expert, or gastroenterologist such as the team at Gastroenterology Associates, if you have symptoms that could indicate colon cancer or other factors placing you in a high-risk category. People over 50 should receive a colonoscopy every 10 years and/or a sigmoidoscopy every 5 years, along with fecal occult blood testing every year, to identify potential abnormalities. If you have additional risk factors such as African-American ancestry, family history of colon cancer or precancerous polyps or inflammatory bowel disease, your doctor will recommend that you receive screening earlier, at 40 or 45 years, depending on the situation.