Marine vs. plant-based omega-3 in breast cancer
While marine-based omega-3 polyunsaturated fatty acids (ω-3 PUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been shown to inhibit breast carcinogenesis, this is not the case with alpha-linolenic acid (ALA), which is plant based. Available evidence on the anti-cancer effect of ALA, the most common ω-3 PUFA in the western diet, is controversial.
A Canadian research team examined the effect of continuous consumption of marine- or plant-based ω-3 PUFA on the pubertal mammary gland and tumour development in a mouse model, with the hypothesis that chronic exposure to ω-3 PUFA would dose-dependently delay the development of tumours and their volume and number. Male HER2-carrier mice, which were crossed with wild-type females, and their offspring were used. Both generations were fed in the same way (so the pups were first exposed to different diets from conception): either flaxseed oil (source of ALA), at different doses, or fish oil (source of EPA and DHA).
The diet with 3% fish oil proved significantly (eight times) more effective that the diet with 10% flaxseed oil in inhibiting tumour development and growth. Fish oil consumption reduced the size of tumours by 60-70% and their number by 30%. And a dose of flaxseed oil was required.
These results show the notable superiority of EPA and DHA over ALA in preventing cancer.
Liu J, Abdelmagid SA, Pinelli CJ, Monk JM, Liddle DM, Hillyer LM, et al. Marine fish oil is more potent than plant-based n-3 polyunsaturated fatty acids in the prevention of mammary tumors. J Nutr Biochem. 2017;27;55:41-52.
Fish-based omega-3 eight times more effective than flaxseed oil at preventing tumours [Internet]. The Economic Times [27 de enero de 2018]. Disponible en: https://economictimes.indiatimes.com/magazines/panache/fish-based-omega-3-eight-times-more-effective-than-flaxseed-oil-at-preventing-tumours/articleshow/62668193.cms