Áine Hennessy

The impact of voluntary food fortification on micronutrient intakes and status in European countries: a review

This review aims to assess the efficacy and safety of voluntary fortification as an option to address the occurrence of inadequate micronutrient intakes in population subgroups in Europe. Although legislation is harmonised across the European Union, fortification practices and patterns of consumption of fortified foods vary considerably between countries. While the proportion of children consuming fortified foods is greater than adults, the proportion of dietary energy obtained from fortified foods is generally low (<10% in Ireland, where fortified foods are widely consumed). There are a few systematic studies on the overall nutritional impact of voluntary fortification, but there are several studies on the impact of fortified ready-to-eat breakfast cereals. The available evidence indicates that voluntary fortification can reduce the risk of sub-optimal intakes of a range of micronutrients at a population level and can also improve status for selected micronutrients (e.g. folate, vitamin D and riboflavin) in children and adults. Although concerns have been raised regarding the potential of food fortification to lead to unacceptably high micronutrient intakes, particularly for those consuming higher amounts of fortified foods, data from national surveys on total micronutrient intakes (including fortified foods) in Europe show that small proportions of the population, particularly children, may exceed the upper intake level (UL) for some micronutrients. The risk of adverse effects occurring in these individuals exceeding the UL by modest amounts is low. In conclusion, voluntary fortification practices have been shown to improve intake and status of key micronutrients in European Union population groups and do not contribute appreciably to risk of adverse effects.

Development, validation and implementation of a quantitative food frequency questionnaire to assess habitual vitamin D intake

BACKGROUND A well-designed, validated quantitative food frequency questionnaire (FFQ) could offer an efficient and cost-effective method for assessing habitual vitamin D intake. The present study aimed to describe the development, validation and implementation of a vitamin D FFQ. METHODS National food consumption survey data obtained from Irish adults (18-64 years) were used to identify foods that contribute 95% of vitamin D intake. A winter-based validation study was carried out for the resulting FFQ in 120 females, including 98 women [mean (SD) 65.0 (7.3) years] and 22 girls [12.2 (0.8) years], using a 14-day diet history (DH) as a comparator. Serum 25(OH)D concentrations were analysed. Validity coefficients were calculated using the method of triads. Cross-classification and Bland-Altman analysis were also performed. RESULTS Median (interquartile range) vitamin D intakes (including the contribution from nutritional supplements) were 5.4 (3.7) and 3.7 (5.9) μg day(-1) from the FFQ and DH, respectively and intakes of vitamin D from food sources were 3.6 (3.1) and 2.4 (2.2) μg day(-1) . The FFQ and DH classified 86% and 87% of individuals into the same and adjacent thirds of wintertime serum 25(OH)D status, respectively. There was a strong association (r = 0.71, P < 0.0001) and no significant systematic or proportional bias observed for the difference between estimates from the FFQ and DH. The validity coefficient for the FFQ was 0.92 (95% confidence interval = 0.80-0.97). Repeatability analysis (n = 56) performed 6-12 months later showed no significant difference in estimates of vitamin D between administrations. CONCLUSIONS The data obtained in the present study indicate high validity and good reproducibility of a short, interviewer-administered FFQ for vitamin D.

Impact of voluntary food fortification practices in Ireland: trends in nutrient intakes in Irish adults between 1997-9 and 2008-10

Because of the discretionary nature of voluntary food fortification in the European Union, there is a need to monitor fortification practices and consumption of fortified foods in order to assess the efficacy and safety of such additions on an ongoing basis. The present study aimed to investigate the nutritional impact of changes in voluntary fortification practices in adults aged 18-64 years using dietary intake data from two nationally representative cross-sectional food consumption surveys, the North/South Ireland Food Consumption Survey (NSIFCS) (1997-9) and the National Adult Nutrition Survey (NANS) (2008-10). The supply of fortified foods increased between 1997-9 and 2008-10, resulting in a higher proportion of adults consuming fortified foods (from 67 to 82 ) and a greater contribution to mean daily energy intake (from 4.6 to 8.4%). The overall nutrient profile of fortified foods consumed remained favourable, i.e. higher in starch and dietary fibre and lower in fat and saturated fat, with polyunsaturated fat, sugars and Na in proportion to energy. Women, particularly those of childbearing age, remained the key beneficiaries of voluntary fortification practices in Ireland. Continued voluntary fortification of foods has increased protection against neural tube defect-affected pregnancy by folic acid and maintained the beneficial impact on the adequacy of Fe intake. Increased consumption of fortified foods did not contribute to an increased risk of intakes exceeding the tolerable upper intake level for any micronutrient. Recent increases in voluntary fortification of foods in Ireland have made a favourable nutritional impact on the diets of adults and have not contributed to an increased risk of adverse effects.

Estimation of the maternal vitamin D intake that maintains circulating 25-hydroxyvitamin D in late gestation at a concentration sufficient to keep umbilical cord sera ≥25–30 nmol/L: a dose-response, double-blind, randomized placebo-controlled trial in pregnant women at northern latitude

ABSTRACT Background In the absence of dose-response data, Dietary Reference Values for vitamin D in nonpregnant adults are extended to pregnancy. Objective The aim was to estimate vitamin D intake needed to maintain maternal 25-hydroxyvitamin D [25(OH)D] in late gestation at a concentration sufficient to prevent newborn 25(OH)D <25–30 nmol/L, a threshold indicative of increased risk of nutritional rickets. Design We conducted a 3-arm, dose-response, double-blind, randomized placebo-controlled trial in Cork, Ireland (51.9oN). A total of 144 white-skinned pregnant women were assigned to receive 0, 10 (400 IU), or 20 (800 IU) µg vitamin D3/d from ≤18 wk of gestation. Vitamin D metabolites at 14, 24, and 36 wk of gestation and in cord sera, including 25(OH)D3, 3-epi-25(OH)D3, 24,25(OH)2D3, and 25(OH)D2 were quantified by liquid chromatography–tandem mass spectrometry. A curvilinear regression model predicted the total vitamin D intake (from diet and antenatal supplements plus treatment dose) that maintained maternal 25(OH)D in late gestation at a concentration sufficient to maintain cord 25(OH)D at ≥25–30 nmol/L. Results Mean ± SD baseline 25(OH)D was 54.9 ± 10.7 nmol/L. Total vitamin D intakes at the study endpoint (36 wk of gestation) were 12.1 ± 8.0, 21.9 ± 5.3, and 33.7 ± 5.1 µg/d in the placebo and 10-µg and 20-µg vitamin D3 groups, respectively; and 25(OH)D was 24.3 ± 5.8 and 29.2 ± 5.6 nmol/L higher in the 10- and 20-µg groups, respectively, compared with placebo (P < 0.001). For maternal 25(OH)D concentrations ≥50 nmol/L, 95% of cord sera were ≥30 nmol/L and 99% were >25 nmol/L. The estimated vitamin D intake required to maintain serum 25(OH)D at ≥50 nmol/L in 97.5% of women was 28.9 µg/d. Conclusions Thirty micrograms of vitamin D per day safely maintained serum 25(OH)D concentrations at ≥50 nmol/L in almost all white-skinned women during pregnancy at a northern latitude, which kept 25(OH)D at >25 nmol/L in 99% and ≥30 nmol/L in 95% of umbilical cord sera. This trial was registered at www.clinicaltrials.gov as NCT02506439.

Variation in iodine food composition data has a major impact on estimates of iodine intake in young children

Background/objectives:The reliability of an estimate of iodine intake is largely dependent on the quality of the food composition data. We aimed to assess the impact of variations in food composition data for iodine and season on the estimates of iodine intake in young children.Subjects/methods:Cross-sectional dietary intake study of Irish 2-year-olds participating in the Cork BASELINE Birth Cohort Study (n=468; 30% of the cohort at the 2-year follow-up) were used to assess the impact of variation in iodine food composition data on estimates of iodine intake, dietary adequacy and risk of exceeding the tolerable upper intake level (UL).Results:Mean (SD) iodine intakes calculated using UK (147 (71)) and Irish (177 (93)) food composition data were significantly different (P < 0.001) (mean difference (95% confidence interval) = 30 (26–33) µg/day) and largely adequate (7–14% below the estimated average requirement). Intakes at the 95th percentile were 138% and 173% of the UL using UK and Irish food composition data, respectively, of which milk accounted for 106% and 150% of the UL. This translated into 22% and 35% of toddlers exceeding the UL, using UK and Irish composition data, respectively. The mean (SD) daily intake of cow’s milk among the 91% of consumers was 309 (208) ml. Intakes of cow’s milk at the 75th and 95th percentiles were 452 and 706 ml, respectively. Using Irish composition data for iodine in cows’ milk, a daily intake of 450 ml could result in a toddler exceeding the UL from milk alone.Conclusions:Variability in food composition has a large impact on assessments of iodine intake, particularly among young children for whom milk contributes a large proportion of their daily nutrient intake. Although this is unlikely to result in long-term adverse effects, our study highlights the need for development of valid biomarkers of individual iodine status.

Vitamin intakes in Irish pre-school children aged 1–4 years

Early childhood is a critical time when dietary intake patterns are forming, which may impact on health in later life. The objective of this analysis was to estimate the mean daily vitamin intake of Irish pre-school children and was based on the National Pre-school Nutrition Survey (2010–2011), which was carried out to establish a database of habitual food and drink consumption in a representative sample of Irish pre-school children aged 1–4 years. A 4 day weighed food record was used to collect food intake data of 500 pre-school children. Analysis of dietary intake data was carried out using WISP g (Tinuviel Software, Anglesey, UK), which contains McCance and Widdowson’s The Composition of Foodsand the Irish Foods Composition Database. The mean intake of selected vitamins and the percentage with intakes below the estimated average requirement (EAR), excluding under-reporters, are shown in Table 1. BMR was calculated using standard equations and cut-off points, calculated as multiples of BMR, were used to identify under-reporters (URs).

The contribution of fortified foods to micronutrient intake in Irish adults aged 18–64 years

The objective of the study was to investigate the contribution of fortified foods to micronutrient intake in Irish adults. Analysis was based on the National Adult Nutrition Survey (NANS), which was carried out between 2008 and 2010 to establish a database of habitual food and drink consumption. A 4-d semi-weighed food record was used to collect food intake data. Analysis of dietary intake data was carried out using WISP g (Tinuviel Software, Anglesey, UK) that is based on McCance and Widdowson’s The Composition of Foods, Sixth edition. The database was updated to identify all fortified foods recorded (6.2% of the 2552 foods consumed) by participants in the food diary. Fortified foods were identified as having one or more micronutrients listed in the ingredients. The mean daily intake (MDI) of micronutrients in consumers of fortified foods and the % contribution of fortified foods to the MDI are reported below.

Interactions between Vitamin D Status, Calcium Intake and Parathyroid Hormone Concentrations in Healthy White-Skinned Pregnant Women at Northern Latitude

Adverse effects of low vitamin D status and calcium intakes in pregnancy may be mediated through functional effects on the calcium metabolic system. Little explored in pregnancy, we aimed to examine the relative importance of serum 25-hydroxyvitamin D (25(OH)D) and calcium intake on parathyroid hormone (PTH) concentrations in healthy white-skinned pregnant women. This cross-sectional analysis included 142 participants (14 ± 2 weeks’ gestation) at baseline of a vitamin D intervention trial at 51.9 °N. Serum 25(OH)D, PTH, and albumin-corrected calcium were quantified biochemically. Total vitamin D and calcium intakes (diet and supplements) were estimated using a validated food frequency questionnaire. The mean ± SD vitamin D intake was 10.7 ± 5.2 μg/day. With a mean ± SD serum 25(OH)D of 54.9 ± 22.6 nmol/L, 44% of women were <50 nmol/L and 13% <30 nmol/L. Calcium intakes (mean ± SD) were 1182 ± 488 mg/day and 23% of participants consumed <800 mg/day. The mean ± SD serum albumin-adjusted calcium was 2.2 ± 0.1 mmol/L and geometric mean (95% CI) PTH was 9.2 (8.4, 10.2) pg/mL. PTH was inversely correlated with serum 25(OH)D (r = −0.311, p < 0.001), but not with calcium intake or serum calcium (r = −0.087 and 0.057, respectively, both p > 0.05). Analysis of variance showed that while serum 25(OH)D (dichotomised at 50 nmol/L) had a significant effect on PTH (p = 0.025), calcium intake (<800, 800–1000, ≥1000 mg/day) had no effect (p = 0.822). There was no 25(OH)D-calcium intake interaction effect on PTH (p = 0.941). In this group of white-skinned women with largely sufficient calcium intakes, serum 25(OH)D was important for maintaining normal PTH concentration.

Antenatal vitamin D exposure and childhood eczema, food allergy, asthma and allergic rhinitis at 2 and 5 years of age in the atopic disease-specific Cork BASELINE Birth Cohort Study

Prospective studies of antenatal and infant vitamin D exposure and atopic disease from extensively characterised, disease‐specific, maternal‐infant cohorts with gold standard analysis of vitamin D status and clinically validated atopic outcomes are lacking. This study aimed to investigate associations between intrauterine vitamin D status and atopic outcomes in an extensively characterised, disease‐specific, maternal‐infant cohort.

Dietary patterns of 24-month old children and associated nutrient intakes and body weight status

Dietary pattern analysis is a useful method to describe the whole diet and evaluate associations with health outcomes and can complement traditional methodologies which use individual foods or nutrients. There are few dietary pattern studies in young children. We aimed to identify the dietary patterns of young children living in Ireland, and investigate associations with body weight status and nutrient intakes and status. Cross-sectional food consumption data of 24-month old children participating in the Cork BASELINE Birth Cohort Study were collected using a 2-day weighed food record (n = 468). K-means clustering was conducted to identify predominant dietary patterns on the basis of the % contribution of food groups to total energy intake (%TE). Body weight status, adequacy of nutrient intake and biomarkers of vitamin D and iron status were compared across the dietary pattern groups. Four dietary pattern clusters were derived from this analysis, two of which differed principally by the type and volume of milk a child consumed, namely “Cows’ milk” [median (IQR): 495 (178) ml/d; 32 %TE] and “Formula” [median (IQR): 368 (193) ml/d; 23 % TE]. A “Traditional” pattern, characterised by higher intakes of wholemeal breads, butter and fat spreads, fresh meat and fruit, with lower intakes of processed meat, and a “Convenience” pattern, characterised by higher intakes of sweets, confectionary and cakes (15 %TE), processed meat, convenience foods (pizza, spaghetti hoops, instant noodles) and lower intakes of fresh meat, were identified. Overall, 7 % of children were classified as obese (>98 centile); however, no significant associations between dietary patterns and body weight (p= 0·121), height (p= 0·327) or body weight status (>98 centile: p= 0·328; BMI z-score: p= 0·170) at 24 months were observed.