Now the study, published in the Lancet, has revealed there is no increased risk of cancer but nor does taking folic acid supplements reduce the risk of cancer. The study compared cancer rates in almost 50,000 people from several different countries over a five-year period. Some participants took the folic acid supplements while others were given a placebo.
In some countries, such as the US, Canada, South Africa and Australia, folic acid – also known as folate or vitamin B9 – is used to fortify flour as part of a drive to reduce neural birth defects. However, in European nations, folic acid is still given in supplement form because of fears that it can disguise the symptoms of anaemia in older people.
The Lancet study, a meta-analysis of 13 worldwide trials, was carried out by the Norwegian Institute of Public Health and the University of Bergen to assess whether folic acid supplements did indeed have any effect on cancer rates.
The researchers found that rates of cancer in patients taking folic acid supplements was 7.7% and 7.3% in patients given the placebo, proving the supplements had no short-term effect on cancer incidences.
The study’s findings also revealed that there is no evidence that folic acid supplements have any effect on specific cancers such as breast, lung or prostate. The UK Food Standards Agency, the UK Medical Research Council, the British Heart Foundation and Cancer Research UK all gave their support to the Lancet study.