Fortifying food, such as wheat and corn flour, with folic acid reduces the risk of spina bifida in babies.

This public health practice was introduced 10 years ago in North America. Now, that practice is being debated in the UK and worldwide. “Are the benefits to the few outweighed by possible harm to some of the many exposed?

Here are the pros and cons.

Dr. Godfrey Oakley, Jr, who played an integral role in the public health decision to fortify food in the US speaks for the proponents.

  • Folic acid fortification worldwide could immediately prevent spina bifida and anencephaly (absence of part or all of the brain) birth defects.
  • Eradicate folate deficiency anemia.
  • Provide human genome stability (maintain the stability of DNA).
  • Reduce homocysteine blood levels, which might prevent heart attacks and strokes.
  • Might prevent colon cancer and Alzheimer’s disease.

Professor David Smith from Oxford University and colleagues from Toronto and Oslo voice their reservations.

  • In animals, a folic acid–rich diet can influence DNA and histone methylation, which leads to phenotypic changes (mutations) in subsequent generations.
  • In humans, increased folic acid intake leads to elevated blood levels of folates and folic acid.
  • High blood concentrations of folic acid may be related to decreased natural killer cell cytotoxicity (important for immunity).
  • High folate status may reduce the response to antifolate drugs used against malaria, rheumatoid arthritis, psoriasis, and cancer.
  • In the elderly, high folate levels combined with low vitamin B-12 levels may be associated with an increased risk of cognitive impairment (reasoning) and anemia.
  • In pregnant women there’s an increased risk of insulin resistance and obesity in their children.
  • Folate has a dual effect on cancer, protecting against cancer initiation but facilitating progression and growth of preneoplastic cells and subclinical cancers.

The bottom line?
More research will be needed to define the risks and identify the groups likely to benefit and suffer from the unforeseen consequences of well-intentioned public health fiat.

My personal interest in this issue was peaked when Professor Smith listed the possible increased risk of dementia.

3/7/08 22:07 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.