Thursday, April 03, 2008
Anti-Cancer
Study Examines Fatty Fish Consumption and Kidney Cancer Incidence
Abstracted by Susan Sweeny Johnson, PhD, Biochem, September 27, 2006, from Wolk, Alieja, Larsson, Susanna, Johansson, Jan-Erik, Ekman, Peter. Long-term Fatty Fish Consumption and Renal Cell Carcinoma Incidence in Women. JAMA, Sept. 20, 2006, 296 (11); 1371-6.
Eighty percent of kidney cancers are renal cell carcinomas (RCC), which three out of every 10,000 people develop. RCC is treatable by surgically removing the kidney if the cancer has not metastasized. It does not respond well to chemotherapy or radiation.
Studies that compare fish consumption with risk of various cancers have shown inconsistent results. However, studies that compare the consumption of omega-3 fatty acids, EPA and DHA, with the risk of cancers have shown an association between the consumption of these fatty acids, along with vitamin D, and the progression and development of cancers, in particular RCC.
Since the omega-3 fatty acids are 20-30 times higher in marine fatty fish than in lean fish, this study compares consumption of fatty fish with consumption of lean fish in 36,664 non-cancerous women aged 39-73 over a period of 17 years. The women reported their diets through a questionnaire substantiated by random checks. The incidence of RCC was not reduced significantly with increased lean fish consumption but was decreased between 44% and 74% in groups averaging more than one meal of fatty fish per week. The higher reduction was in groups that consistently consumed that much fish over 10 years.
The researchers suggest a follow up study to measure blood concentrations of omega-3 fatty acids and vitamin D.