Fish oil linked to cancer treatment

Fish oil may boost the effectiveness of a common treatment for breast cancer, research suggests.

In tests on rats, it appeared to combat cancer at the genetic level, making tumours more responsive to the drug tamoxifen.

The widely used drug works by blocking the female hormone oestrogen’s ability to fuel breast cancer.

Omega-3 fatty acids, abundant in fish oil, could prove to be a safe and beneficial booster for tamoxifen therapy, said the US researchers.

Rats with breast cancer were fed either a 17 per cent fish oil diet or a 20 per cent corn oil diet for eight weeks. In each case the oil supplement was given with or without tamoxifen.

Analysis of the tumours showed that omega-3 fatty acids in the fish oil increased the activity of genes promoting cellular specialisation, or differentiation.

This indicates an anti-cancer effect, since cancer cells are highly undifferentiated. Combining fish oil and tamoxifen also reduced the activity of genes linked to tumour growth and cancer spread.