Below is some advice on how to prevent cancer:

    Eat blueberries

    Aside from being a healthy and delicious snack, the blueberries contains pterostilbene, which has important colon(结肠) cancer-fighting. ____. Blueberries also offer a large dose of vitamins C. So at breakfast, try to take in a cup and a half of blueberries in your cereal or yogurt, or mixed with other berries.

    Relax

    ____? Find ways to relax and you may reduce your chances of developing cancer. Purdue University researchers tracked 1,600 men over 12 years and found that half of those with high levels of worry died during the study period. Only 20 percent of the optimists died before the study were completed, while 34 percent of the extremely anxious men died of some type of cancer.____!

    Break a Sweat

    ____. In a study of 29,110 men published in The International Journal of Cancer, men who exercised just once a week had a percent lower risk of prostate cancer than men who didn't work out at all. The better the frequency and intensity of the exercise, the bigger the reduction in risk, according to the study.

    ____

    There's no question that secondhand smoke kills, A recent American Journal of Public Health study showed that nonsmokers working in smoky places had three times the amount of carcinogen（致癌物）in their body than nonsmokers working in smoke-free locations. What's worse, their levels of the carcinogen rose 6 percent for every working hour. Many states have banned smoking in all workplaces, bars and restaurants. The message is clear: Do whatever you can to avoid the cloud of smoke.