Diet Rich in Omega-3 Reduces Risk of Breast Cancer by 33%
Scientists in Canada have just reported unequivocal experimental evidence that omega-3 can fight breast cancer. Dr David Ma and his colleagues at the University of Guelph in Ontario1 conducted an experiment involving laboratory mice. A group of the mice were fed omega-3s in the diet. These mice displayed a 33% reduction in the number of tumors and 30% reduction in size of the tumors compared to the control group, which did not get sufficient omega-3. It has long been suspected that diet may play a role in reducing the risk of cancer. Ma and his colleagues have provided the first hard scientific evidence to support this hypothesis.
Breast cancer is the most common cancer in women all over the world. Diet has been anecdotally linked to the incidence of this particular type of cancer. Epidemiological studies have shown significant differences in breast cancer incidence between women who consume a western diet compared with women who consume Asian diets. Western women typically consume larger quantities of the harmful omega-6 fatty acids, such as linoleic acid, compared with Asian women who consume more omega-3s.
Omega-3 fatty acids
Omega-3 fatty acids are polyunsaturated fatty acids found in cold water fish and plant oils. The “3” indicates the position of the first double bond in relation to the methyl end of the carbon chain. In this case, the double bond is situated after the third carbon atom from the terminal methyl group. It is these double bonds that qualify the molecule as polyunsaturated. They are known as essential fatty acids (EFAs) because, although they are required for healthy functioning, they are not manufactured in the body and must therefore be taken in as part of the diet or in a dietary supplement.
Why is it necessary to use mice for cancer research?
Diet-based studies in both humans and in animals are difficult to control. It just isn’t practical to measure the diet adequately in these studies. Epidemiological studies associating omega-3s with reduced risk of breast cancer have been inconclusive. The fat-1 mouse was created to provide an objective way to study the impact of omega-3 exposure with the development of breast tumors. The fat-1 gene, derived from the roundworm C. elegans, enables the mice carrying the gene to synthesize their own omega-3 from the less desirable omega-6 fatty acid in the diet.
What is the significance of these results?
This is groundbreaking stuff. While nobody is suggesting that female infants be transfected with the fat-1 gene themselves, these experiments help to illustrate the importance of a healthy diet that includes omega-3 fatty acids as early as possible. These data also open the door for future studies of omega-3 and other nutrients in the development of other types of cancer. While we wait for these additional studies, it may be wise to add a high-quality omega-3 supplement to your diet.
1Ma D, et al, “Mammary Tumor Development is Directly Inhibited By Lifelong Omega-3 Polyunsaturated Fatty Acids,” J of Nutr. Biochemistry. Retrieved on 2013.