Dietary changes can reduce cancer risk. Omega-6 and omega-3 are common essential dietary fats and diet rich in omega-6 or linoleic acid (LA) increases prostate cancer risk. Diets rich in omega-3 reduce prostate cancer risk. The omega-3 family of fatty acids is comprised of alpha linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The same enzymes that convert ALA to EPA and DHA also convert LA to arachidonic acid (AA). These two pathways compete for the same enzymes.
15-lipoxygenase-1 (15-LO-1) is an enzyme, which metabolizes omega-6 LA, whose levels are elevated when prostate cells are becoming cancerous. The goal of this study was to see if diet could alter 15-LO-1 levels. Mice were fed diets with high omega-6 LA, high omega-3 stearidonic acid (SDA) or no fats. The mice had been exposed to prostate cancer cells.
Mice were studied for the relationships between the tendency to develop prostate cancer and the omega-6:omega-3 ratios in the diet. PSA and 15 LO-1 levels were tested and the study showed that a combination of EPA and DHA was most effective in inhibiting prostate cancer cell growth. The ideal ratio of omega-6:omega-3 is between 1:1 and 4:1. The ratio in the current Western diet is 20:1.
The study showed the ability of omega-3 SDA to modulate the growth of prostate cancer cells, promote apoptosis and reduce PSA levels. The omega-3 was shown to reduce 15-LO-1 levels, possibly by competing with the enzymes for the LA to AA pathways. Omega-6:omega-3 ratios can be manipulated by dietary changes.
CONCLUSION: Prostate tumors can be modulated by manipulation of the omega-6:omega-3 ratios in the diet. EPA and DHA are dietary agents which can modulate the growth of prostate cancer cells. “The antitumerogenic omega-3 fatty acids can modulate the protumerogenic omega-6 LA and AA enzymatic pathways.”
NOTE: Read about how the Hunter-Gatherer Diet can alter the omega-6/omega-3 ratios and alter cardiovascular disease.
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