天博体育

Ask the doctor

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Q. My doctor says I have a small skin cancer on my scalp, but it's not melanoma. Do I really need to have it removed?

A. It's true that melanoma is the most dangerous type of skin cancer, because it can spread throughout the body. You definitely need to have any melanoma removed, to try to excise it before it spreads. Two other types of skin cancer, basal cell carcinoma and squamous cell carcinoma, are more common than melanoma. It sounds like you have one of those. They spread only rarely, but they do grow larger. Not only is this disfiguring, but delay in removing them makes it harder to remove them with only a minimal scar. And cancers on the scalp, when they become large, can be particularly hard to remove.

In the journals

Vitamin D and omega-3 fatty acid supplements have had mixed results when it comes to preventing heart attacks, strokes, and cancer in people who have already developed these problems or are at high risk for them. Yet a new study published online Nov. 10, 2018, by The New England Journal of Medicine found they may actually prevent these conditions among people who have never had these problems before.

Researchers recruited almost 26,000 people, ages 50 and older, who had no history of heart disease or cancer. The participants were divided into four groups. People in one group were given daily doses of 2,000 international units of vitamin D (an amount found to be linked to lower disease risk in observational studies) and 1 gram of a drug called Lovaza, which contained 840 milligrams of omega-3s (two to four times the amount in two servings of fish per week). The second group took vitamin D and a placebo, the third group took the omega-3s and a placebo, and the final group took two placebos. After more than five years, the researchers found that those given omega-3s were 28% less likely to suffer a heart attack compared with those given a placebo. Those who ate fewer servings of fish (less than the average of 1.5 servings per week) appeared to have a greater benefit from the additional omega-3s while those with higher fish intake had minimal benefit.

A healthy diet should go heavy on vegetables and skip alcohol, sugary drinks, and processed foods.

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Most of the time when someone gets cancer, it's because of bad genes or bad luck. But as many as four in 10 cancers may be preventable. And diet likely plays an important role in reducing (or increasing) your risk.

It's no surprise that vegetables and fruits are thought to reduce cancer risk, according to Teresa Fung, adjunct professor in the Department of Nutrition at the Harvard T.H. Chan School of Public Health and faculty editor of Healthy Eating, a Special Health Report from 天博体育 Publishing (available at www.health.harvard.edu/special-health-reports). It probably also won't shock you to learn that bacon, fast food, and sugary drinks fall into the opposite category. But how can you know for sure which foods to eat and which to avoid?

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Research we're watching

For years, many have speculated that taking vitamin D and omega-3 fatty acid supplements might help to prevent heart attacks, strokes, and certain cancers. But a study by Harvard researchers published online November 10, 2018, by The New England Journal of Medicine has found that the benefits may be more limited than originally hoped.

The results of the Vitamin D and Omega-3 Trial (VITAL), which enrolled more than 25,000 people and ran for more than five years, showed that while omega-3 supplements did appear to reduce the risk of heart attack, particularly among African Americans, they did not appear to be effective in preventing stroke or cancer. Vitamin D supplements also saw few benefits when it came to preventing heart attack, stroke, or cancer 鈥� but they were associated with a drop in cancer deaths in people who had taken the supplements for at least a year or two.

Ask the doctor

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Q. A friend has melanoma, and his doctor wants to use a new kind of treatment that boosts the immune system. Can you tell me more?

A. The immune system exists to attack foreign things that enter the body, such as germs. Certain cells of the immune system recognize and attack foreign things. Cancerous cells make chemicals that are not made by normal cells, chemicals the immune system should recognize as foreign. Unfortunately, eight million people around the globe die of cancer each year after their immune systems fail to destroy the cancer. Why do their immune systems fail?