Yet, cancer is preventable and one-third of all cancers are curable if detected early and treated properly. However, as you get older, your risk for cancer does increase. For example, if you’ve reached the age of 40, your odds of getting some form of cancer over the next 20 years are about 1 in 11. Once you hit 60, your 20-year risk is 1 in 5 (for women) and 1 in 3 (for men).
You can’t keep yourself from getting older. But you can change other risk factors for cancer. Unfortunately, many people don’t know which cancers are most common, which are most deadly, which are easiest to detect, and most importantly, what can lower your risk.
Here’s a guide to some major cancers and what you can do to dodge them.
• Lowering your risk. "Research on fruits and vegetables, fat, meat or dairy foods, and organochlorine pesticides hasn’t panned out," says Regina Ziegler of US National Cancer Institute’s Division of Cancer Epidemiology. "And it’s too simple to say that soy is protective." Soy’s plant estrogens may act like estrogen rather than compete with the hormone. "So we can’t rule out that soy increases breast cancer risk."
The strongest lead: "Obesity is now widely accepted as a risk factor for breast cancer," Ziegler explains. "Heavy women have a lower risk of premenopausal breast cancer, but once women hit their 40s, and certainly by their 50s, being overweight increases their risk."
"Physical activity probably reduces the risk of breast cancer, but we don’t know how much you need," says Ziegler. Whether the exercise needs to be strenuous or not is still an open question.
The only other consistent link with diet: "Alcohol, even in moderation, seems to increase the risk," she adds. However, alcohol may not raise the risk of breast cancer in women who get at least 300 mcg a day of the B-vitamin folate (folic acid). In one study, women who drank one serving of alcohol a day and took a multivitamin — which typically supplies 400 mcg of folate — had a 25 percent lower risk of breast cancer than those who didn’t take a multi.
• Lowering your risk. Although most people expect to see a fiber-rich diet heading the list, recent trials have found no fewer polyps in people who were told to eat fiber-rich grains, fruits and vegetables than in those who were not. Still, Tim Byers, co-chair of the American Cancer Society’s Nutrition and Physical Activity Guidelines Advisory Committee, maintains that "the biggest body of evidence suggests that fruits and vegetables are protective."
Other studies find a higher risk in red-meat-eaters, smokers, and people who drink more than one serving of alcohol a day. In contrast, folate seems to lower colon cancer risk. And few people realize that extra pounds pose a threat to your lower gastrointestinal tract.
"Weight control and staying physically active – either alone or in combination – can lower your risk," says Byers. "Some researchers argue that the risk only drops with vigorous physical activity, but many studies show that the biggest risk comes from being sedentary. If you just get off the couch and do something, your risk begins to drop."
And although fiber doesn’t seem to lower the risk of new polyps, other things have. "Calcium supplements and aspirin or other NSAIDs (non-steroidal anti-inflammatory drugs) seem to lower the risk by 10 to 20 percent," says Byers.
x-rays, analyzing cells in sputum, and examining bronchial passages with fiberoptic instruments don’t seem to help. That leaves only one strategy: Prevention.
• Lowering your risk. Obviously, smoking dwarfs all other causes of lung cancer. But 15 percent of lung cancers in women occur in non-smokers. For non-smoking men, it’s 5 percent. Why?
"Radon, passive smoke, and genetic predisposition increase the risk," says Yale’s Susan Mayne. "A history of chronic bronchitis or asthma may also raise the risk by causing chronic inflammation in the lungs."
The good news: "In both non-smokers and smokers, fruits and vegetables lower the risk of lung cancer," says Mayne. " Some studies find that people who eat more carotenoids (like alpha- or beta-carotene) have a lower risk, but it looks like carotenoids are just a good indication of how much fruits and vegetables you’re eating."
• Lowering your risk. When it comes to diet and prostate cancer, "nothing is firmly established," says Edward Giovannucci of the Harvard School of Public Health.
But the large SELECT (Selenium and Vitamin E Cancer Prevention Trial) is now testing whether selenium and vitamin E can prevent the disease, as they appear to do in earlier studies. "And lycopene or something else in tomatoes seem to lower the risk," Giovannucci adds. Men who consumed tomato sauce at least twice a week had a 35 percent lower risk of advanced prostate cancer than men who ate tomato sauce less than once a month.
In contrast, "diets high in red meat and dairy foods are associated with an increased risk, though we’re not sure why," says Giovannucci. "High calcium intakes – above about 1,500 mg a day – may partially explain the link with dairy foods." The recommended intake for calcium is 1,200 mg a day for men aged 50 or older so you can’t assume that more is better.
The newest finding: "Men who consume at least three servings of fish a week have close to half the risk of advanced prostate cancer compared to men who eat fish rarely," says Giovannucci.
Chalk up one more reason to eat seafood – as if avoiding sudden cardiac death weren’t enough!