A: Just like us, chickens and cows can develop cancer. But cancer is largely a disease of the aging process, and animals raised for food are slaughtered while they're young. If, by some chance, a meat product does contain cancerous cells, cooking it will kill them. And even if your steak tartare came from a cancer-afflicted cow, there's no evidence to suggest you'd suffer any ill effects. Of much greater concern is eating too much red and processed meat, which are linked to cancers of the digestive system. You should also avoid meat cooked at very high temperatures (such as pan-fried or flame-grilled), because the extreme heat produces carcinogens.
Q What should I look for on a sunscreen label?
A: Choose a product marked "broad spectrum"—meaning it protects against UVA and UVB rays—with an SPF of at least 30. But keep in mind that SPF measures how well a sunscreen blocks UVB rays (which cause burns)—not UVA rays (which penetrate deeper and speed aging). There are no labeling standards specifically indicating protection against UVA rays, so be sure your sunscreen has some combination of the chemical UVA-screening ingredients oxybenzone, avobenzone, and ecamsule, and/or at least one of the physical blocking agents titanium dioxide or zinc oxide.
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Q: Nearly every night I get heartburn. Could this increase my risk for a heart attack?
A: No. Heartburn involves the digestive system, not the cardiovascular system. It's the sensation caused by acid reflux, a condition in which gastric acid rises up from the stomach into the esophagus. But chronic heartburn can be a risk factor for a precancerous disorder called Barrett's esophagus. Over time gastric acid damages the lining of the esophagus, and in about 1 percent of cases, this damaged tissue will become cancerous. The problem is that Barrett's esophagus does not cause symptoms, so people with persistent reflux should be monitored closely, typically with endoscopy exams once a year. If found, Barrett's esophagus can be reversed with radiofrequency ablation, an endoscopic procedure involving targeted thermal energy.
Q: Should I be worried about radiation from backscatter airport scanners?
A: These machines emit low levels of radiation—about .1 microsievert per scan, compared to 10 units for every 1,000 miles you fly on a plane. Some scientists argue, though, that backscatter X-rays could cause a small increase in cancer risk, particularly melanoma, because the majority of the scanner's radiation is deposited on the skin. Additionally, the FDA doesn't monitor airport X-ray machines, and if a malfunction occurs, travelers could be exposed to a much higher dose of radiation. Still, the health risk posed by these scanners is very minor, although populations that are more sensitive to radiation may want to opt for the pat-down instead. These include travelers over 65 (the body's cells are less able to repair DNA damage as you age), women with BRCA-1 or BRCA-2 gene mutations, cancer patients, pregnant women, and children.
Keep Reading: Which screenings are safe?
Q: I like white wine, not red. Am I still getting any health benefits?
A: Red wine, made with the skin of the grape, contains more of certain antioxidants than white, which is made after the skins are removed. One powerful antioxidant in red wine, resveratrol, may help prevent cancer and protect the heart by blocking damage from free radicals and reducing inflammation. But consuming any alcohol in moderation can raise HDL ("good" cholesterol), prevent artery damage caused by LDL ("bad" cholesterol), and reduce the formation of blood clots. So both wines offer benefits—in responsible amounts.
Keep Reading: Learn the truth about Oprah, Dr. Oz, and resveratrol
Q: Is one drink a day okay if I have a family history of breast cancer?
A: How's your heart health? While alcohol has been shown to increase the risk of breast cancer, it can also lower the risk of heart disease. Each year far more American women die of heart disease than die of breast cancer; thus, for the average person, the benefits of alcohol outweigh the risks. But if you've inherited a harmful BRCA gene mutation, your risk of breast cancer is dramatically higher than that of the average woman. For a known carrier, drinking any alcohol is probably a bad idea. For others, the odds still favor having the occasional glass of wine.
Keep Reading: The truth about breast self-exams