The Irish Longitudinal Study on Ageing (TILDA) also found low or deficient folate rates increased with age, from 14% among those aged 50-60 years to 23% among people over 80 years old.
Low folate status was more common in those who lived alone, smokers and the obese – two risk factors that were modifiable, according to study lead author and TILDA research fellow Dr Eamon Laird.
“There are striking differences in the prevalence of deficiency across different lifestyle factors such as obesity and smoking,” he added.
“Our findings will provide useful data to help inform public health policy –particularly regarding the proposition of mandatory folic acid and/or vitamin B12 fortification.”
In contrast, countries such as the United States, where folic acid fortification is mandatory, rates of low folate status are around 1.2% in older adults compared with 15% in Ireland.
The country currently practices voluntary food fortification, with some foods such as ready-to-eat cereals enriched with micronutrients such as folic acid. The issue though is the inconsistency of this approach resulting in inadequate exposure over time.
‘Derailing what is of benefit to the majority’
In 2016, the Food Safety Authority of Ireland (FSAI) highlighted the need for women of childbearing age to have higher folic acid intakes to reduce the incidence of severe birth defects in Ireland.
The authority’s report recommended either mandatory fortification together with voluntary fortification and advice on supplementation as one option or voluntary fortification together with advice on supplementation as another course of action.
Both options were presented to an expert group on folic acid set up by the country’s minister for health as viable solutions to reduce the occurrence of neural tube defects in babies and prevalence of folate deficiency in older adults.
Despite talk of action, Ireland has not introduced mandatory folic acid fortification – despite a number of committees looking into its possibility.
In November 2017, Dr Peter McKenna, clinical director of the National Women and Infant’s Health Programme, told the Oireachtas Committee on the Eighth Amendment that moves to block the introduction of folic acid to the diet was due to the “tyranny of the articulate, whereby some derail what is of benefit to the majority”.
“Our study suggests that the current custom of voluntary food fortification is ineffective in preventing deficiency or low status of these vitamins among older people,” added Dr Laird.
“The results are of relevance not just for Ireland but for all countries that do not have mandatory fortification.”
TILDA provides strong data
Further outcomes of the study found low or deficient vitamin B12 was more common in smokers (14%), people who lived alone (14.3%) and those from lower socio-economic backgrounds (13%).
Additionally, the use of both vitamin B12 and folic acid supplementation was low, with higher rates in women than men but less than 4% overall taking supplements of either vitamin.
“The high rates of B-vitamin deficiency seen in the older adult population are of concern and, given that this can be easily treated with fortification, this has significant policy and practice implications for Government and health services,” said professor Rose Anne Kenny, principal investigator of TILDA.
Professor Kenny added that the Trinity College Dublin TILDA study had consistently assisted policy makers by providing strong evidence based data on which to make recommendations.
The study had also assisted with information of most vulnerable people and therefore those who should be targeted.
Source: British Journal of Nutrition
Published online ahead of print: doi:10.1017/S0007114518001356
“Voluntary fortification is ineffective to maintain the vitamin B12 and folate status of older Irish adults: evidence from the Irish Longitudinal Study on Ageing (TILDA).”
Authors: Eamon J. Laird, Aisling M. O’Halloran, Daniel Carey, Deirdre O’Connor, Rose A. Kenny and Anne M. Molloy