Folic acid linked to breast health risk

Women who take folic acid during pregnancy may increase their risk of breast cancer in later life, a new study suggests.

Women who take folic acid during pregnancy may increase their risk of breast cancer in later life, a new study suggests.

The unexpected findings cast doubt on the safety of one of the most widely used and longest established supplements in pregnancy. But the researchers say women should not stop taking the supplements, and that the most likely explanation for the findings is chance.

Folate, which occurs naturally in dark, green, leafy vegetables, is important to foetal growth and is known to protect against birth defects.

In the study, researchers from Aberdeen and Bristol followed up almost 3,000 women who took part in a trial of folate supplements in the late 1960s. They found that women given high doses of 5mgs a day were twice as likely to develop breast cancer and had a 20 per cent higher risk of death from any cause up to 35 years later.

But, in the British Medical Journal, Professor Marion Hall and colleagues say the findings may be due to chance, and women planning to become pregnant should take folic acid supplements as recommended.