Cod Liver Oil lowers breast cancer risk in study

Increased vitamin D levels during youth, from the sun and the diet, may reduce the risk of breast cancer later in life by over 30 per cent, suggests a new epidemiological study.

The study, which appears in the March Cancer Epidemiology Biomarkers & Prevention, looked at 972 women with newly diagnose invasive breast cancer and 1,135 randomly selected healthy controls and interviewed to assess vitamin D-related variables, such as sunlight exposure (outdoor activity), cod liver oil intake and milk consumption.

After adjusting for potential confounding factors, Knight and her co-workers found that increased exposure to sunlight during adolescence was associated with the highest protection against breast cancer risk later in life, with a risk reduction 35 per cent.

Significant risk reductions were also observed for increased cod liver oil intake (24 per cent risk reduction), and drinking at least 10 glasses of milk per week was associated with a 38 per cent risk reduction.

"We found strong evidence to support the hypothesis that vitamin D could help prevent breast cancer. However, our results suggest that exposure earlier in life, particularly during breast development, maybe most relevant," concluded the researchers.

The study does have several important limitations, notably being based on recall of dietary habits early in life as well as outdoor exposure, both of which are susceptible to recall errors from the participants.

Steve - while we acknowledge the limitations of this study, the most convincing conclusion can be made from those who supplemented with Cod Liver Oil. While it could be difficult to remember how much sunlight they were exposed to and how much milk they drank, they'd surely remember taking Cod Liver Oil!