10 ways to reduce your cancer risk

Cancer is now one of the leading causes of death in the Philippines. And the most common types of cancer in our country, arranged by sex, according to the 2005 estimates of the Philippine Cancer Society, are as follows:

• Men: 1) lung, 2) liver, 3) colon/rectum, 4) prostate, 5) stomach, 6) leukemia, 7) nasopharynx, 8) oral cavity, 9) non-Hodgkin Lymphoma; and 10) larynx.

• Women: 1) breast, 2) cervix uteri, 3) lung, 4) colon/rectum, 5) ovary, 6) thyroid, 7) liver, 8) leukemia, 9) corpus uteri, and 10) stomach.

Even though a number of factors can increase your risk of getting or dying of cancer, many of them can be controlled by the choices you make every day. Evidence suggests that two-thirds of annual cancer deaths are related to diet, weight, exercise, and tobacco exposure. In today’s column, we’ll look at the role that many lifestyle behaviors can play in raising or lowering your risk of canEdit Articlecer development.

You may have heard conflicting news reports about what can or can’t help you in terms of cancer prevention. This can make it difficult to know what to believe. Although not every new discovery may pan out, there are some prevention methods that can make a real difference. Here are 10 of them:

1. Don’t smoke. Staying away from tobacco, or deciding to stop using it, is one of the best health decisions you can make. It has been linked to several types of cancer — including cancers of the bladder, cervix, esophagus, kidney, pancreas, voice box (larynx), and lung.

The most common cancer associated with smoking is lung cancer. That’s because when you inhale cigarette smoke, your lungs are exposed to more than 4,000 chemicals, including over 40 known to cause cancer. Your risk of smoking-related cancers increases with the length of time and number of cigarettes you smoke. However, quitting reduces your risk of lung and other cancers — no matter how many years you’ve been smoking (An Apple a Day, August 9, 2010 ). It also lowers your chance of death from other causes, including heart attack and stroke.

2. Eat fruits and vegetables. It is recommended that you eat at least five servings of fruits and vegetables every day. The reason: These foods are loaded with vitamins, minerals, antioxidants, and other valuable substances that may lower the risk of cancers of the lung, esophagus, stomach, and colon. They’re also low in calories, which can help with weight control.

Fruits and vegetables containing vitamin C and beta carotene, which forms vitamin A, may be particularly beneficial. That’s because these antioxidant vitamins can protect against cell damage, which may play a role in cancer development. Good sources include dark leafy green vegetables as well as red and orange fruits and vegetables. Supplements may offer some of the same vitamins. However, they’re not meant to take the place of fruits and vegetables.

3. Limit fat in your diet. Some studies suggest that high-fat diets or high intakes of certain types of fat may be linked to several cancers — including colon, lung, and postmenopausal breast cancer. This may be because high-fat diets tend to be higher in calories and may increase obesity. However, more research is needed to understand which types of fat should be avoided and how much of each alters cancer risks.

Meanwhile, it is best to follow current dietary guidelines on fat consumption which recommend keeping total fat intake between 20 and 30 percent of your total daily calories — with most of fats coming from sources of polyunsaturated and monounsaturated fats, such as fish, nuts, and vegetables (including canola and olive oil). (An Apple a Day, October 12, 2010). Also, get less than 10 percent of your daily calories from saturated fats and keep consumption of trans fats as low as possible.

4. Maintain a healthy weight. Being overweight or obese can make you more likely to develop postmenopausal breast cancer as well as cancers of the colon, endometrium (uterus), esophagus, and kidney. Evidence also suggests that obesity increases the risk of cancer of the prostate, liver, gallbladder, pancreas, stomach, ovary, and cervix.

Excess weight may contribute to cancer development by affecting your metabolism, immune function, and levels of several hormones — including insulin and estrogen. Avoiding weight gain as an adult, especially after menopause, may reduce the risk of some cancers. Some studies have shown that losing excess weight can decrease the odds of developing breast cancer after menopause because it can keep estrogen levels down.

5. Be physically active. A growing number of evidence suggests that people who are more physically active have lower risks of cancers than those who are more sedentary. These cancers may include those of the breast, colon, and endometrium. For men, prostate cancer is included in this list.

The benefits of physical activity may largely be traced to weight control. However, being active may also have an impact on cancer development by regulating sex hormones and insulin levels boosting the immune system. Current exercise guidelines have recommended that all adults engage in 30 minutes of moderate to vigorous physical activity on five or more days of the week. However, to reduce the risk of breast and colorectal cancers, 45 to 60 minutes of moderate to vigorous exercise a day, on most days of the week, is considered optimal.

6. Curb alcohol consumption. Alcohol consumption is a concern because it increases the risk of cancers of the mouth, pharynx, esophagus, liver, colon and rectum, and breast. Regularly having more than one drink a day for women and two drinks a day for men, can raise your risk even more. So can combining alcohol consumption and smoking.

If you’re a regular drinker and don’t get enough folate in your diet, you may be at a particularly higher risk of breast and colorectal cancers. Folate is a B vitamin found in leafy green vegetables, citrus fruits and juices, and dried beans and peas. It’s recommended that most adult women get 400 mcg a day.

7. Limit exposure to radiation. Exposure to radiation is a clearly established cause of cancer. Ultraviolet (UV) radiation — which comes from the sun, sunlamps or commercial tanning beds — is the most common source. It’s also the primary cause of skin cancer. Common preventive recommendations are to stay out of the midday sun whenever possible, wear protective clothing, and use sunscreen with an SPF of at least 15.

High levels of ionizing radiation (from X-rays, radiotherapy, or radon gas) can lead to the development of leukemia, thyroid cancer, and breast cancer. There’s also evidence that this type of radiation may cause cancers of the stomach, colon, esophagus, bladder, and ovaries. Radon gas, which has been linked to lung cancer, is another environmental risk factor.

8. Protect against infections. Infections caused by viruses are recognized as a risk factor for several types of cancers. Some of the most common include: human papillomavirus (HPV), a sexually transmitted infection and the most common cause of cervical cancer; hepatitis B and hepatitis C virus (HBV and HCV), which can increase your risk of liver cancer; and human immunodeficiency virus (HIV), the virus that causes AIDS.

Avoiding risky behaviors, such as engaging in unprotected sex, having multiple partners, and sharing needles with intravenous drug users can help lower your risk of contracting these viruses.

9. Consider chemoprevention. Chemoprevention agents have been studied, or are currently under study, for many cancers. The best known is tamoxifen, the first chemoprevention drug to receive approval from the US FDA. Tamoxifen is used to prevent breast cancer in women who are over age 35 and are at high risk of the disease. Aspirin and other nonsteroidal anti-inflammatory drugs have been shown to reduce the risk of colorectal cancer and some other cancers. Yet, these drugs are not routinely recommended for chemoprevention because they can have serious side effects.

If you’re interested in chemoprevention for a particular type of cancer, talk with your doctor about what type of drug may be appropriate for you.

10. Get recommended screening exams. Although screening for certain cancers may not prevent these diseases, it can increase your chances of discovering cancer early, when treatment is most likely to be successful. For instance, the best way to detect breast cancer early is with an annual mammogram, usually starting at age 40. Pap tests for cervical cancer, should be done at age 21, or within three years of the first time you had sex.

Colorectal cancer screening is usually done at age 50. With a colonoscopy, that may mean every 10 years. If you’re unsure of what screening exams you should be getting, or when and how to get them, talk with your doctor. He/she can provide guidance, as well as refer you to other specialists, who can give you additional information and advice on the prevention of other forms of cancer.

Additional resources: American Cancer Society (www.cancer.org); Centers for Disease Control and Prevention -Cancer Prevention and Control (www.cdc.gov/cancer); and National Cancer Institute (www.cancer.gov).