Do you spend lots and lots of hours texting on your phone or playing video games? Sitting for long periods of time may be as bad for your body as smoking cigarettes, says Dr. David Agus. Dr. Agus has a lot to share about health and wellness and how our bodies work. He's an oncologist, a doctor who treats people with cancer. Dr. Agus is also a professor of medicine and engineering at the University of Southern California and has helped develop new drugs and diagnostic tools. As an oncologist, he studies how the environment and the way we live — like eating junk food and getting very little exercise — can contribute to the growth of different cancers. Collecting data on how our bodies act and react will give him and other researchers important information needed for new treatments, and practical ways for us to live healthy, cancer-free lives.