Several new studies suggest coffee helps prevent breast, prostate, head and neck cancers.
While too much coffee can cause health problems, such as ulcers, the new research suggests generous amounts of it are most strongly linked to lower cancer rates—between two and five cups daily, or even more, depending on the study and cancer type.
While too much coffee can cause health problems, such as ulcers, new research suggests generous amounts of it are most strongly linked to lower cancer rates—between two and five cups daily, or even more, depending on the study and cancer type. (Image courtesy onemhz) |
People who drank about four or more cups a day had a 39 percent decreased risk of oral cavity and pharynx cancers combined, the investigators found. Data on decaffeinated coffee was too sparse for detailed analysis, they added, but indicated no increased risk. Tea intake wasn’t associated with head and neck cancer risk.
“What makes our results so unique is that we had a very large sample size… we had more statistical power to detect associations between cancer and coffee,” said said lead researcher Mia Hashibe of the University of Utah.
The research is published in the advance online issue of the journal Cancer Epidemiology, Biomarkers & Prevention, published by the American Association for Cancer Research.
In another study, presented at the association’s Frontiers in Cancer Prevention Research Conference last December, Harvard University researchers presented data showing that men who drank the most coffee had an up to 60 percent decreased risk of lethal and advanced prostate cancers.
Results of a third study published in the January issue of the same journal showed a decreased risk of gliomas, or brain tumors, associated with coffee. This link was found among those who drank five or more cups of coffee or tea a day, according the researchers from Imperial College, London.
And yet a fourth study, in the April 2008 issue of Cancer Epidemiology, Biomarkers & Prevention, found that at least two or three cups of coffee a day can either reduce the risk of breast cancer or delay its onset.
This effect is related to estrogens, female sex hormones, said the scientists, from Lund and Malmö universities in Sweden. Certain metabolic products of these hormones are known to be carcinogen, and various components of coffee can alter the metabolism so that a woman acquires a better configuration of various estrogens, investigators said. Caffeine also hampers cancer cell growth.
In the study, researcher Helena Jernström and colleagues studied the coffee-drinking habits of women including nearly 460 breast cancer patients at Lund. Coffee’s effect, the scientists said, varied depending on which version women have of a gene called CYP1A2, which produces an enzyme that breaks down estrogen and coffee. Half of the women had a variant called A/A, while the others had either A/C or C/C.
“Those women who had one of the C variants, and who had drunk at least three cups of coffee a day, developed breast cancer considerably more seldom than women with the A/A variant with the same coffee consumption. Their cancer risk was only two thirds of that of the other women,” Jernström said.
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