Tuesday, February 1, 2011

Bread Matters

The impact of Folic Acid Fortification in Australia

Just over a year after the introduction of mandatory folic acid fortification in wheat flour for bread making, Australian researchers have set out to determine the impact it has had on the blood folate levels of Australians.

Research suggests an adequate intake of folate pre conception can reduce the incidence of neural tube defects in newborn infants. This has lead to the introduction of government sponsored health promotion campaigns encouraging women of child-bearing age to supplement with folic acid. In 1995, voluntary fortification was introduced and successfully increased the populations’ blood folate levels, and resulted in a reduction in neural tube defects between 1996 and 2006. In September 2009, fortification of 2-3mg of folic acid per kg of wheat flour for bread making was mandated under Standard 2.1.1 of the Food Standards Code, resulting in 0.135mg of folic acid per 100g of bread (approx 2-3 slices), or around half the recommended dietary intake (RDI) of folate. Note: the RDI is higher for woman of childbearing age.
 
Over 20,000 blood samples were used for the study between April 2009 and April 2010, as well as April 2007 and April 2008 (used as baseline). These samples tested for serum and red blood cell (RBC) folate levels in diagnostic pathology labs.

Between April 2009 and April 2010 the prevalence of low serum folate levels decreased by 77% (from 9.3% to 2.1%) and the prevalence of low RBC folate levels decreased by 85% (from 3.4% to 0.5%). The even better news is that while concerns were originally raised that women of child-bearing age may not be huge consumers of bread, the prevalence of low RBC folate levels amongst women of child-bearing age (15-50) was reduced to only one sample from 609 samples tested (0.16%). There was also a 31% increase in mean serum folate and a 22% increase in mean RBC folate levels for the samples tested.

It’s important to note the samples are not necessarily representative of the whole Australian population as they were obtained unexpectedly from those for whom a blood folate test was requested for the investigation of a possible folate deficiency, and are therefore likely to be biased towards low folate levels. Another limitation is that different patients were studied pre and during the mandatory fortification period and both samples would have included blood samples from those patients with coeliac disease or others on wheat free diets. Lastly, the authors stated they do not know the number of patients that might have already been taking a folate supplement.

Although no evaluation has been made to date on the impact of mandatory folic acid fortification of wheat flour for bread making on the incidence of neural tube defects, the results of this study are somewhat impressive in relation to the reduction of folate deficiency in the Australian population.

Already one of the leading sources of fibre in the diets of Australians, low in fat, a source of protein, thiamin, niacin and folic acid, there are plenty of reasons to enjoy the goodness of bread!

Reference:

Brown et al. The impact of mandatory fortification of flour with folic acid on the blood folate levels of an Australian Population. MJA (2011) 194: 65-67