I could not agree more with Colapinto and colleagues’ interpretation of the results of their study of folate status in Canada.1 I’d like to raise awareness of the need to protect another population group: older adults.
An overwhelming proportion of older people aged between 65 and 94 years had elevated levels of total folate in a seven-year cohort (1997–2004).2 The levels were elevated in 84% of people obtaining folic acid exclusively from their diet (i.e., not taking folic acid supplements) as opposed to 100% in those taking multivitamins. Moreover, total folate levels were found to increase at an annual rate of 234 ng/mL (p < 0.001) since the beginning of fortification in 1998 and had not reached a plateau by 2004.
Because this population is not at child-bearing age, the only advantage of fortification is a reduction of homocysteine levels. Elevated levels of homocysteine, however, were reduced from 13% to 7% by 2000, but they increased again to 16%. Thus, the benefit of folic acid fortification in older adults was not maintained despite continuously increasing levels of total folate.
Older adults are at the highest risk of malignancy, so exposing them to further increases of folate seems unreasonable and possibly dangerous. I urge Health Canada to consider all populations before deciding to increase the concentration of folic acid in products consumed every day by everyone.
Notes
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