Trend in prevalence of neural tube defects in Quebec

Abstract

Fortification of flour, which began in early 1997 and gradually became widespread, is a very plausible explanation for the timing, shape, and magnitude of the decrease in NTD prevalence observed in Quebec and other Canadian provinces. An increase in FA supplement use may have played only a minor role. Birth Defects Research (Part A) 67:000-000, 2003.

Folate fortification and supplementation—Are we there yet?

“…A significant decline in the prevalence of NTD was reported also from Canada [35][36][37][38][39] and Chile [40] where fortification became mandatory in 2000 and from China where folate supplementation has been given [41]. In the USA an estimated decline in prevalence of NTD from 10.6 cases per 10,000 live births in 1995-1996 (pre fortification) to 7.5 cases per 10,000 in 1999-2000 (post fortification) was reported [42].…”

Folic Acid Supplementation and Cancer Risk: Point

“…However, folic acid supplementation seems to reduce the risk of stroke (52) and NTDs (53)(54)(55). In fact, the overwhelming evidence for the protective effect of periconceptional folic acid supplementation on the development of NTDs (53)(54)(55) led to the eventual mandatory folic acid fortification in the United States and Canada in 1998 (55)(56)(57), resulting in a significant 15% to 50% reduction in the rate of NTDs (58)(59)(60)(61)(62)(63). Despite the unequivocal success in reducing NTDs rates, the debate on mandatory folic acid fortification has not ceased, and as a matter of fact, the controversy over this public health policy has intensified, partly because of an uncertain role of folate in cancer development and progression (64,65).…”

Heart defects and other malformations in the Inuit in Canada: a baseline study

“…It was estimated that folic acid fortification would increase the average daily intake of folic acid by 80-100 µg/day. This has been shown to be true of the general Canadian population, where, since fortification was introduced, substantial increases in RBC folate have been seen and there is evidence that rates of spina bifida are decreasing (33,34). Since the arctic and subarctic diet is known to be high in meat, fish and fowl (and especially low in foods containing folic acid) it remains unclear whether folic acid enrichment has had a similar beneficial effect in the north.…”