Zinc may prolong prostate cancer survival if disease is diagnosed early
MedWire News: Preliminary study results show that men who are diagnosed with early stage prostate cancer could improve their chances of surviving the disease if they eat a diet rich in zinc.
The highest quartile of marine omega-3 docosahexaenoic acid (DHA) was also associated with a 30% reduced risk for prostate cancer-specific death compared with the lowest quartile.
“Our results suggest men diagnosed at early stage prostate cancer may be sensitive to dietary zinc levels... Omega-3 DHA may also be beneficial... with inflammation being a potential common mechanism,” say Mara Meyer, from the Harvard School of Public Health in Boston, Massachusetts, USA, and colleagues.
The study was presented at the American Association for Cancer Research 101st Annual Meeting in Washington, DC, USA, this week.
The team compared dietary intake of zinc and fatty acids with time to death from prostate cancer or any cause among 525 Swedish men diagnosed with the disease between 1989 and 1991. An early-stage diagnosis was defined as stage T0–T2/M0.
Chronic systemic inflammation is associated with enhanced prostate cancer progression, and zinc and fatty acids affecting inflammatory responses are promising targets for increasing cancer-specific survival, they explain.
Participants completed a dietary questionnaire, based on the Swedish diet, and were followed until 2009. In all, 218 men died from prostate cancer, and 257 died from other causes.
No association was seen between zinc intake and overall or prostate-specific mortality. However, men with early stage prostate cancer and the highest zinc intake (15.7 mg or more) were 74% less likely to die from the disease compared with men who consumed the lowest zinc levels (12.8 mg or less).
Men diagnosed in the early stages also had a 45% reduced risk for prostate cancer death if they were in the highest, rather than lowest quartile for consumption of omega-3 DHA, but DHA was not associated with death from any other causes.
In addition, the highest quartiles of consumption of saturated, monounsaturated, and polyunsaturated fats showed no association with prostate cancer survival.
“But studies such as this one... definitely give us some clues to pursue.”
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By Sarah Guy