April 21, 2009 (Denver) -- When it comes to cancer, a little wine may be a very good thing. But the news isn't as upbeat regarding barbecued steaks and green tea.
So suggest the latest studies on food and drink, presented this week at the annual meeting of the American Association for Cancer Research.
Researchers at the Yale School of Public Health studied more than 500 women with non-Hodgkin's lymphoma, a cancer of the lymphatic system. At the time of their diagnosis, the women were asked a battery of questions regarding alcohol: whether they drank, what they drank, how much they drank, and for long they had been drinking. Then they were followed for eight to 12 years.
"We found that wine had a protective effect," says Xuesong Han, a doctoral candidate in cancer epidemiology.
Among the findings:
- About three-fourths of women who drank at least 12 glasses of wine over their lifetime were alive five years after diagnosis, compared with two-thirds of those who never drank wine.
- Thirty-five percent of never-drinkers relapsed within five years vs. 30% of wine drinkers.
The longer a woman drank, the lower the chance she would suffer a relapse or die within five years of diagnosis, Han says.
Patients who had been drinking wine for at least 25 years prior to diagnosis were 26% less likely to relapse or develop a secondary cancer and 33% less likely to die over the five-year period, compared with non-wine drinkers.
The protective effects of wine were strongest among women with diffuse large B-cell lymphoma, the most common type of non-Hodgkin's lymphoma. Women with this type of cancer who drank more than six glasses of wine a month were about 60% less likely to relapse or die within five years, compared with non-wine drinkers.
Beer and liquor consumption did not appear to affect lymphoma risk.
Yawei Zhang, PhD, who also worked on the study, says for most women, a few glasses of wine a week may help to protect against the cancer. Women with a family history or other risk factors for non-Hodgkin's lymphoma, such as those with impaired immune systems, might particularly benefit, she tells WebMD.
"But if you have risk factors for breast cancer, you should avoid wine. Studies have linked any type of alcohol to poor outcomes," Zhang says.
Very Well-Done Steak Tied to Pancreatic Cancer
A second study showed that eating very well-done red meat -- to the point of being burned or charred -- may increase the risk of pancreatic cancer by almost 60%.
Kristin Anderson, PhD, associate professor of epidemiology at the University of Minnesota School of Public Health, said the finding was linked to consumption of very well-done steaks prepared by frying, grilling, or barbecuing. Cooking in these ways can form carcinogens, which do not form when meat is baked or stewed.
The study involved 62,581 healthy men and women who filled out surveys asking what type of meat they ate, how they prepared their meat, and how well they liked their meat done. Over the course of the next nine years, 208 participants developed pancreatic cancer.
In addition to turning down the heat, Anderson offers these cooking tips:
- Cut away parts of red meat that are burned or charred.
- Microwave meat for a few minutes and pour off the juices before cooking it on the grill.
- When grilling, do not let flames lap at the meat. Wrap meat in foil to protect it from the direct flame.
- Cook meat in water or another liquid to prevent it from getting too hot.
So what about advice to cook meat until it is well done to avoid food-borne bacteria such as salmonella that can cause serious illness, or even death?
"Everything in moderation," advises Andrea Burnett-Hartman, MPH, a doctoral student at Fred Hutchinson Cancer Research Center in Seattle whose own work showed that charred meat was not linked to the development of precancerous growths in the colon.
"You don't want it red in the middle," she tells WebMD. "And choose poultry over red meat."
Green Tea Doesn't Mix With Cancer Drug
A third study suggests some cancer patients should avoid the so-called "miracle herb" green tea. It interferes with the metabolism of Velcade, a drug often prescribed for multiple myeloma, says Thomas Chen, MD, a neurosurgeon at the University of Southern California Keck School of Medicine in Los Angeles.
The research was done on cancer cells in the test tube and in animals. "We could not perform a clinical trial [of humans] because our theory was that drinking green tea was harmful," says researcher Alex Schonthal, PhD, associate professor of molecular microbiology at the University of Southern California.
"We discovered that various green tea constituents, in particular epigallocatechin gallate (EGCG) and other polyphenols, effectively prevented tumor cell death induced by [Velcade]," he says.
Patients shouldn't assume that "natural" products like green tea are harmless, says Peter G. Shields, MD, deputy director of the Lombardi Comprehensive Cancer Center in Washington, D.C.
If you're prescribed Velcade and drink green tea, you may want to discuss the findings with your doctor, he says. "While these studies are performed in animals and in [the test tube], we do inform patients about possible interactions based on a lot less data," Shields tells WebMD.