Try to stay active, even in front of a screen

Dear Readers: Welcome to the second day of our new “Ask the Doctors” column. As an internist and primary care physician at UCLA Health, my approach to medicine is to understand that I don’t have all the answers – that I have to learn new topics and review old topics all the time.

Sometimes, I can provide answers right away. But sometimes, I have to stop and reassess. Medicine has seen many breakthroughs since I graduated from medical school nearly 20 years ago, and evidence has changed many dogmatic ways of practice.

Objective, non-biased data are important to the practice of medicine. Doctors must understand how that data can be applied to one person or to large groups of people.

You met my colleagues Dr. Eve Glazier and Dr. Elizabeth Ko yesterday and learned about their approach to health and wellness. My column focuses on commonsense answers based upon scientific literature. As I increase my professional knowledge, I hope to provide people with thoughtful and deliberate interpretations of medical science that people can use to direct their own health.

Dear Doctor: My job requires me to sit in front of a computer for at least eight hours a day. When I come home, I usually watch television for a few hours before going to bed. Is being so sedentary bad for me?

Dear Reader: Unequivocally, yes. Many studies of many types have found increased death rates among people who sit for prolonged periods. The biggest problem is being sedentary in front of a television.

The average American watches more than four hours of television per day. Some studies have found that for every additional two hours in front of the television, the risk of diabetes increases 14 to 20 percent.

Here’s why: Sitting for prolonged periods decreases insulin sensitivity, meaning your blood sugar rises. Add to that the types of sugary foods that are often eaten while watching television, and you have the creation of a serious health problem. If you’re sedentary throughout the day, exercise can help ease the negative impact, but not completely make up for it.

So for starters, watch less television or, if you do watch television, put an exercise bike in front of the screen. Second, if you have a job in which you sit for long periods, take three-minute breaks every 30 minutes to stretch and walk around a little. Every little bit of activity helps.

Robert Ashley, M.D., is an internist and assistant professor of medicine at the University of California, Los Angeles.