Omega -3 fats were found to have no significant effect on total tumor burden or affect latency period, tumor weight, or tumor regression. (Sally J. Feltner. Influence of type and level of dietary polyunsaturated fat on incidence of chemically -induced mammary tumors and on selected immune responses in rats. (Unpublished dissertation, 1988)
These were the results of my dissertation a couple of decades ago; however a new study wakes us up to the possibility that omega 3 fish oils (EPA and DHA) may have an positive effect (less growth) of tumors when fed fish oils as an adjunct to immunotherapy in mice.
What happened here?
In my study there were no effects on tumor incidence; the new study found that omega -3 fatty acids may have a positive benefit if they are used with certain cancer treatments with the ultimate suppression of tumor growth. In my study, however, “the animals fed a high or low fish oil diet (omega 3)) produced a significantly higher antibody titer in response to sheep red blood cells than those fed the low or high corn (omega 6) oil diet.” This indicates a positive effect on the immune system at least in animals.
Study results of omega-3/6 fatty acids can be complex resulting in conflicting results in both human and animal studies.
This may be due to the imbalance of intake between the 3’s and the 6’s. in the Standard American diet. The optimal ratio of omega-3 fats in the diet is in a range of 2:1 to 4:1 (6s to 3s). The typical ratio in the U.S. diet is 16:1 – that is bad!! This means that inflammation can “run rampant”, increasing your risk of heart disease, diabetes, and arthritis. We simply eat too many omega-6 and not enough omega-3 fatty acids. Additional studies are planned. Very interesting.!