The Impact of Diet and Physical Activity on Cancer
How big is it?

By Annette Rich

What is cancer? The term “cancer” is actually used for more than 100 different diseases. And it affects everyone – it doesn’t matter if you are young or old, rich or poor. After heart disease, cancer is the leading cause of death in the United States. All cancers involve the malfunction of genes that control cell growth and division in the body. About 5 percent of all cancers are hereditary, meaning you could have been born with a higher risk of developing a certain type of cancer depending on the genes you inherited from your parents. However, most cancers are not the result of renegade family genes gone bad, but from damage to those genes that occurs during a person’s lifetime. That damage can come from your environment, hormones, sunlight or the personal choices you make every day. We all know the risk of smoking and developing cancer, but can what you eat, and how much you exercise really play major roles in whether or not you develop cancer?
Diet and physical activity are currently very popular and important areas of cancer research. While tobacco use is the single largest preventable cause of cancer, diet and exercise have shown to be key elements in the prevention of cancer themselves.
According to the American Cancer Society, one-third of cancer deaths in 2007 were related to being overweight or obese, being physically inactive, and having poor nutrition, and they could have been prevented.
In Texas, more than 25 percent of the population is considered to be obese. And after eliminating tobacco use, maintaining a healthy weight appears to be the most important aspect to avoiding the possibility of cancer. There have been several studies in the last few years showing an increasing link between being overweight or obese to many types of cancer including breast, esophageal, colon, endometrial and kidney. Those studies suggest that diet accounts for about 30 percent of all cancers in the United States. Lung disease is the leading cause of cancer death among women in the United States with breast cancer pulling up a strong second. Postmenopausal, overweight women with breast cancer have a worse prognosis even at earlier stages of diagnosis. There also seems to be an association between obesity and breast cancer relapse. An obese patient is also more likely to be diagnosed at a later stage of breast cancer due to the difficulty in identifying an area of concern during routine screening.
What you eat can increase or decrease your risk of cancer. We have all heard the term, “An apple a day keeps the doctor away.” And it is true - diets high in fruits and vegetables may protect you from several kinds of cancer. Red apples offer more than just fiber. And the color is key. Studying large groups of people from many countries, researchers have shown that the risk of developing some cancers is lower in people who have diets high in foods containing the phytochemical lycopene. Lycopene is the chemical that gives tomatoes and certain other fruits and vegetables their bright red color. Foods that are high in lycopene include tomatoes, watermelon, pink grapefruit, pink guava, papaya and red bell pepper. Processed tomato products such as pasteurized tomato juice, soup, sauce, and ketchup contain the highest concentrations of lycopene available to the body. Diets rich in tomatoes may help reduce your risk of several different types of cancer, especially cancers of the prostate, lung and stomach. Keep this in mind next time you are cruising through the produce aisle.
Along with weight control and nutrition, physical activity can substantially decrease the risk of cancer. Scientific evidence shows that physical activity may reduce the risk of certain cancers as well as help maintain a healthy body weight. The American Cancer Society reviews and updates its guidelines on nutrition and physical activity every five years. The current guidelines, published in 2006, suggest that carving out just 30 minutes a day, for five days a week, for moderate physical activity can make a difference. Increasing that to 60 minutes a day would be ideal. Walk with a friend to catch up instead of talking on the phone, or walk with your kids to school and teach them the importance of exercise. The American Cancer Society also recommends that children and adolescents get at least 60 minutes of physical activity on five days a week.
There’s an added benefit of maintaining a healthy weight, eating smart and being more active to decrease your risk of developing cancer - you also lower your risk of that pesky number No. 1 killer in women, heart disease.