Vitamin D link to better breast cancer survival rate

WOMEN who take vitamin D after being diagnosed with breast cancer may increase their chances of survival, new research from the Irish Cancer Society shows.

Women who took vitamin D supplements after diagnosis had a 20% higher survival rate compared to those who didn’t, the study found.

Professor Kathleen Bennett, who supervised the study by cancer researchers based at the Royal College of Surgeons in Ireland, outlined her team’s findings, stating: ‘Previous studies have found that higher blood levels of vitamin D, which can come from our diet, sunlight or supplements, is associated with increased breast cancer survival.

‘Our study suggests that vitamin D supplementation might be useful for women diagnosed with breast cancer. Large clinical trials are already under way overseas to look into this further.’

The research found vitamin D users to be younger on average, to be less likely to smoke and to have lower tumour stage and tumour grade progression – all factors more likely to be associated with better survival rates – compared to non-users.

However, Dr Robert O’Connor, head of research at the Irish Cancer Society, urged caution, saying: ‘Before rushing out to buy vitamin D supplements, we urge women with breast cancer to first talk to their medical team.

‘Vitamin D use can cause health issues and each woman’s cancer is unique and will require personalised treatment. While this is an important preliminary study, the findings only show an association, and not causal link.’

For the study, anonymised pharmacy purchases of almost 5,500 women with breast cancer aged 50-80 between 2000 and 2011 were provided by the National Cancer Registry of Ireland.

Breast cancer is the second most common cancer affecting women in Ireland, with more than 3,100 women diagnosed each year. While the number of breast cancer survivors is increasing, 700 women still die from breast cancer each year in Ireland.

‘Only show an association’