Written by Susan Sweeny Johnson, PhD, Biochem. Of 36,664 non-cancerous women, those who ate one meal of fatty fish per week over a period of 17 years, showed a significant decrease of 44% – 74% in Renal Cell Carcinoma.
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 inverse association between the consumption of these fatty acids, along with vitamin D, and the progression and development of cancers, in particular RCC. (1,2,3)
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.
Source: Wolk, Alicja, Susanna C. Larsson, Jan-Erik Johansson, and Peter Ekman. “Long-term fatty fish consumption and renal cell carcinoma incidence in women.” Jama 296, no. 11 (2006): 1371-1376.
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Posted July 25, 2008.
Reference:
- Larsson, SC, et al. Dietary long-chain n-3 fatty acids for the prevention of cancer: a review of potential mechanisms. Am J Clin Nutr. 2004;79:935-45.
- McCabe, AJ, et al. Docosahexaenoic acid reduces in vitro invasion of renal cell carcinoma by elevated levels of tissue inhibitor of metalloproteinase-1. J Nutr Biochem. 2005;16:17-22.
- Fujoika, T, et al. Prevention of renal cell carcinoma by active vitamin D3. World J Surg. 2000;24:1205-10.