Two Main Causes of Cancer

Cancer is the second leading cause of death in the United States. It begins when genes mutate and allow cells to grow without control. Gene mutations can be inherited or acquired. Acquired mutations are caused by repeated exposure to carcinogens like those in cigarettes or unhealthy foods. Two main causes of cancer are smoking and aging.

Aging

• Though anyone of any age can get cancer, getting older is one of the biggest risk factors. Aging is partly caused by oxidants that can damage DNA. Cancer, which is considered an aging disease, often starts with oxidants that are produced through normal metabolism. Antioxidants like vitamins A and C minimize damage from oxidants, but most humans don't get enough nutrients to ward off cancers.

Aging and Nutrition

• Aging isn't just the number of years since we were born; it's also how quickly the parts of our bodies wear out. Our bodies age partly because we don't get enough of the right nutrients. We eat too much fat and not enough vegetables, fiber, fruit and calcium. Not eating foods that contain antioxidants--which can boost the immune system and fight disease--can lead to many forms of cancer. Poor diet is one of the main contributors to aging, which is one of the two main cancer risks.

Aging From Lack of Physical Activity

• Lack of physical activity causes you to age and gain weight. Too little exercise and being overweight increase the risk for breast, colon, kidney, uterus, esophageal and endometrial cancer. Being overweight makes your body produce too many hormones that cause cancer to grow. Most people tend to put on extra weight as they age, and those who don't usually have very active lifestyles.

Smoking

• Using tobacco is the most preventable cause of cancer. Cigarette smoke has an enormous amount of oxidants. While most people know smoking causes lung cancer, they don't realize tobacco use causes a higher risk of esophageal, stomach, kidney, bladder, pancreas, cervical, uterine, head, neck and liver cancers as well. Cancer that starts in blood cells is more likely in smokers than non-smokers.

Considerations

• According to the National Cancer Institute, lung cancer is the leading cause of cancer deaths in the United States. About 80 percent of women and 90 percent of men who die of lung cancer had cancer that was caused by smoking. A report by the surgeon general showed that tobacco smoke contains more than 4,000 chemicals, and at least 43 of them cause cancer.

Research

• A May 2008 article in "Science Daily" explains how researchers at the Oregon Health and Science University Cancer Institute studied a protein that normally prevents cancer. The protein, FANCD2, becomes ineffective when exposed to cigarette smoke. FANCD2 repairs DNA damage and causes the death of faulty cells, but smoking stops production of the protein. When your body doesn't produce enough FANCD2, the resulting DNA damage leads to cancer.