In the US, cancer accounts for more than more than half a million deaths per year. Many of us associate cancer risk with a family history of cancer but only 5 percent to 10 percent of cases are believed to be the result of an inherited mutation.
Far more cancer cases are caused by controllable factors, such as using tobacco, drinking alcohol, consuming an unhealthy diet and being sedentary. Adopting healthier habits is not a guarantee someone will avoid cancer but it can significantly reduce the risk.
Tobacco, obesity, poor diet and physical inactivity account for two-thirds of cancers in the United States.
The message that cancer risk can be lowered, though not eliminated, by leading a healthy lifestyle doesn't appear to resonate with most Americans.
Recommendations for healthy living and prevention of other diseases (such as diabetes and high blood pressure) include: maintain a healthy weight, be physically active, eat mostly plant-based foods and avoid tobacco, alcohol and red meat.
The American Cancer Society estimates 14 percent of cancer deaths in men and 20 percent in women are attributable to excess weight. The problem with extra pounds seems to be the changes they cause in the body. Being overweight has been linked to inflammation and scientists believe that may cause changes at the cellular level that can spur the development of cancer cells.
According to the CDC, 63 percent of Americans are either overweight or obese. Obesity has been implicated in health problems such as heart disease and diabetes, but people don't seem to make the same kind of connection with cancer.
Excess body fat increases the risk of some of the most common cancers -- colorectal, kidney, endometrial, pancreatic and postmenopausal breast cancers.
While some factors, like tobacco use, which accounts for 30 percent of cancer deaths, have been known for years, individual situations are complex, making it hard to discern who will be affected the most by changing their diet or beginning an exercise routine.