We Need To Sit Less At Work and Home

According to a meta-analysis of 43 observational studies published in the Journal of the National Cancer Institute, American's sedentary lifestyle is leading to increased risks of various types of cancers. The analysis looked at the relation between time spent viewing TV and the risk of some types of cancers, as well as the relation between other sedentary behaviors such as using a computer at home or at work and the risk of some types of cancer. The conclusion was clear. The more you sit, the more likely it is that you will have colon, endometrial, and lung cancer.

Today, adults typically spend 50-60% of their day sitting. Think about it. When you wake up, you are likely to sit for breakfast or to relax before you leave. When you leave, you are either sitting on a car, on a bus, or a train. When you arrive at work, you are likely to sit at a desk. And then when you get home again, you are likely to once again sit down before going to sleep. 

The problem with being sedentary is that we end up expending less energy, which translates into weight gain and a deteriorating physiology. It can also lead to cravings, which increase our consumption of unhealthy foods and in many of us the desire to smoke. All of this is strongly related with obesity and diabetes, which increase the risk of cancer.

Physical activity, on the other hand, reduces the risk of cancer. However, the analysis found something very interesting. Even among individuals who engage in physical activity at recommended levels, the risk for increased cancer is still higher if they engage in sedentary behaviors. So, even if you regularly exercise but also spend a lot of time sitting, you are still at an increased risk of various types of cancer. That's a big problem.

The reason why sitting may lead to greater risks of cancer even if you exercise regularly is that the human body has adapted to the use of muscles on a regular basis throughout the day. Using your muscle releases chemicals into the body that are critical to your health. For example, a few hours of sitting inhibits the production of lipoprotein lipase, an enzyme that helps remove fats from the bloodstream. This, in turn, leads to a drop of HDL, also known as good cholesterol.