Voluntary fortification is ineffective to maintain the vitamin B 12 and folate status of older Irish adults: evidence from the Irish Longitudinal Study on Ageing (TILDA)

Mandatory fortification of staple grains with folic acid and/or vitamin B 12 (B 12 ) is under debate in many countries including Ireland, which has a liberal, but voluntary, fortification policy. Older adults can be at risk of both deficiency and high folate status, although little is known on the actual prevalence and the major predictors. Population prevalence estimates from older adults ( n 5290 ≥50 years) from the Irish Longitudinal Study on Ageing (TILDA) (Wave 1) are presented here. Measures included plasma total vitamin B 12 and folate, whereas predictors included detailed demographic, socio-economic, geographic, seasonal and health/lifestyle data. The prevalence of deficient or low B 12 status (45 nmol/l) was observed in 8·9 %, whereas high B 12 status was observed in 3·1 % (>601 pmol/l). The largest positive predictor of B 12 concentration was self-reported B 12 injection and/or supplement use (coefficient 51·5 pmol/; 95 % CI 9·4, 93·6; P =0·016) followed by sex and geographic location. The largest negative predictor was metformin use (−33·6; 95 % CI −51·9, −15·4; P