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Vitamin D intakes in 18-64-y-old Irish adults
T R Hill1, M M O'brien, K D Cashman
1Department of Food and Nutritional Sciences, University College, Cork, Ireland.
Objective:
To estimate vitamin D intakes in a representative sample of Irish adults and to assess the contribution of foods to these intake estimates.
Design:
Vitamin D intakes in 1379, 18-64-y-old adults from the North/South Ireland Food Consumption Survey were estimated using a combination of new analytical data for vitamin D in foods, determined by HPLC, and used to revise recipe calculations, together with existing data from McCance and Widdowson's The Composition of Foods, 5th Edition plus supplements.
Results:
The total mean daily intake (MDI) of vitamin D (1 microg=40 IU) from all sources was 4.2 microg. The MDI was significantly higher (P<0.001) when the contribution from nutritional supplements was included (4.2 microg) compared with food sources only (3.2 microg). Men had significantly higher intakes (4.4 microg) than women (4.0 microg; P<0.001), which increased significantly (P<0.001) with age in both sexes. Meat/meat products (30.1%), fish/fish products (14.3%) and eggs/egg dishes (9.1%) were the main contributors to vitamin D intake. Supplements contributed 6.8 and 12% to MDI in men and women, respectively. In all, 74% of adults had an MDI of vitamin D that was less than the median (5 microg) of the recommended daily range of 0-10 microg.
Conclusion:
The findings of this study suggest that a large number of Irish adults have low vitamin D intakes. This, along with emerging evidence of low vitamin D status in at least some population subgroups, suggests that strategies to increase vitamin D intakes, including fortification of food, should be investigated.
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