Safe addition of vitamins and minerals to foods: setting maximum levels for fortification in the Netherlands

Background In 2004, the European Court of Justice decided that the prohibition of fortification with vitamin A, vitamin D, folic acid, selenium, copper, and zinc in the Netherlands conflicts with the principle of free movement of goods in the European Union. This decision led to a change in the Dutch policy, resulting in a more flexible handling of requests for exemption from this prohibition to fortify. Therefore, an investigation was proposed in which it would be determined whether a general exemption could be granted for food fortification with a certain maximum safe amount per micronutrient. Aim of the study To develop a risk assessment model to estimate maximum safe fortification levels (MSFLs) of vitamins and minerals to foods on the Dutch market, and to evaluate these levels to derive allowed fortification levels (AFLs), which can be used for a general exemption. Methods We developed a risk assessment model to estimate MSFLs of vitamins and minerals to foods on the basis of existing models. We used European tolerable upper intake levels in combination with national food consumption data to estimate MSFLs for fortification of foods for several age groups. Upon extensive stakeholder dialogue, the risk manager considered these estimated MSFLs and the final AFLs for a general exemption were set. Results For folic acid, vitamin A, and vitamin D, the MSFLs were calculated in the risk-assessment model. Children up to 6-years old were the group most sensitive to folic acid fortification, and they had an MSFL of 0 μg/100 kcal, but following a risk management evaluation, this was upgraded to an AFL of 100 μg/100 kcal. The MSFL for vitamin D was 3.0 μg/100 kcal (children 4–10 years old), and the risk manager increased this to an AFL of 4.5 μg/100 kcal. Children up to 10 years old, men, and postmenopausal women were the groups most sensitive to vitamin A fortification (MSFL = 0 μg/100 kcal). Because these groups represent a large part of the population and because of the seriously harmful effects of excessive vitamin A, the risk manager did not allow a general exemption. Conclusions The combination of a risk assessment model and risk manager evaluation led to the setting of AFLs for general exemption of fortification with folic acid and vitamin D. This model is also applicable for other micronutrients, for which an UL is derived, and in other countries.     

Estimation of Vitamin D Intake Based on a Scenario for Fortification of Dairy Products with Vitamin D in a Tehranian Population,Iran

Objective: The aim of this study was to evaluate possible effects of food fortification practices on vitamin D intake in adults.

Design and setting: This was designed as a cross-sectional, population-based study.

Subjects: We investigated vitamin D intake in a population-based sample of 5224 adults, using a validated food frequency questionnaire. A theoretical model was conducted to evaluate the hypothetical effects of dairy product fortification.

Results: Dairy had the highest mean of vitamin D intake among food groups. If all types of milk were fortified by vitamin D (42 IU/100 grams of milk), the mean intake of vitamin D would reach 132 ± 148 (92(180)) IU/day. If both milk and yogurt were fortified to 42 IU/100 g and 89 IU/100 g, respectively, the average mean vitamin D intake from foods in this population would increase from 84 ± 88 IU/day to 308 ± 240 IU/day. As the fortification level increased, the proportions of young people with more than the recommended daily allowance (RDA) of vitamin D increased from 1.1% to 77.4% in men and from 1.4% to 80% in women, but none of them achieved the tolerable upper intake level (UL) of vitamin D.

Conclusion: The proposed fortification scenario would provide enough vitamin D intakes by RDA in a population aged between 18 and 50 years (about 80% of the population), with none of them achieving ULs.     

Vitamin D deficiency in Australia and New Zealand: What are the dietary options?

Measurement of serum vitamin D levels in population samples has revealed unexpectedly high prevalence of vitamin D deficiency among children, adults, the elderly and other vulnerable groups in Australia and New Zealand. The new Nutrient Reference Values report has established dietary recommendations for vitamin D of between 5 and 15 µg/day, depending on age. Dietary intakes of vitamin D in Australia typically fall in the range of 2–3 µg/day, below intakes in comparable countries. Dietary intake of vitamin D is currently dependent on consumption of a few key foods, notably margarine and oily fish. Current models of healthy eating do not deliver the recommended amounts of vitamin D and need review. Consideration should be given to the range of foods fortified with vitamin D, which is currently limited. Higher dietary intakes of vitamin D in overseas countries have been achieved through the fortification of margarine, milk and breakfast cereals. Increased voluntary fortification of dairy products with vitamin D would be a safe and simple means of increasing vitamin D intakes in Australasia in the short term. The relatively high dietary recommendation for vitamin D for elderly people cannot be met through the existing food supply and supplementation appears to be a desirable option for many.     

预包装食品中维生素D强化情况调查

摘要:目的　了解预包装食品中维生素D强化的情况。方法　根据GB14880-2012的规定,在南京5家大型超市进行调查。结果　有36个品牌、共110种食品进行了维生素D的强化,65.5%的食品属于调制乳粉、调制乳、豆粉类;食品维生素D强化剂量均符合食品营养强化剂使用标准,人造黄油的添加量最高,最低的为糊状食品;九大知名品牌产品数约占所有维生素D强化食品的58.2%;76.4%的维生素D强化食品未明确标注维生素D2或维生素D3。结论　结果显示维生素D强化食品种类仍然不多且关于维生素D的标示信息不全。应增加维生素D的强化食品种类,并考虑强制性对一些食品进行维生素D强化。     

Vitamin D intake in Australian adults and the modeled effects of milk and breakfast cereal fortification

ObjectiveVitamin D intake from foods or supplements is a safe and attractive means to improve vitamin D status of populations. The aim of this study was to help identify population subgroups that would benefit most from efforts to increase intake. To do so, we investigated which personal characteristics are associated with vitamin D intake in an Australian population and modeled possible effects of expanded food fortification practices.MethodsWe investigated vitamin D intake in a population-based random sample of 785 adults, using a validated food frequency questionnaire, and assessed associations with personal and behavioral characteristics. We identified vitamin D food sources and modeled the hypothetical effects of blanket fortification of milk and breakfast cereals.ResultsAverage total vitamin D intake was 4.4 (±4.0) μg/g and below adequate intake for most participants in all age and sex subgroups. Higher intake was associated with being female, having a serious medical condition, energy intake below the median, and vitamin D supplement use (all P < 0.05). The “meat, fish, and eggs” food group contributed most to total vitamin D intake (51%), followed by dairy products and related foods (43%). If all milk and breakfast cereals were to be fortified with vitamin D, the average intake of vitamin D from foods would increase from 3.6 (±2.4) μg/d to 6.3 (±3.2) μg/d, with similar increases in all age and sex subgroups.ConclusionsVitamin D intake in Australia is generally below recommended levels, and few personal characteristics help to identify subgroups with low intake. Blanket vitamin D fortification of milk and breakfast cereals would substantially increase average vitamin D intake in Australian adults of all ages.     

Effect of a voluntary food fortification policy on folate, related B vitamin status, and homocysteine in healthy adults

BACKGROUND: Mandatory folic acid fortification of food is effective in reducing neural tube defects and may even reduce stroke-related mortality, but it remains controversial because of concerns about potential adverse effects. Thus, it is virtually nonexistent in Europe, albeit many countries allow food fortification on a voluntary basis. OBJECTIVE: The objective of the study was to examine the effect of a voluntary but liberal food fortification policy on dietary intake and biomarker status of folate and other homocysteine-related B vitamins in a healthy population. DESIGN: The study was a cross-sectional study. From a convenience sample of 662 adults in Northern Ireland, those who provided a fasting blood sample and dietary intake data were examined (n = 441, aged 18-92 y). Intakes of both natural food folate and folic acid from fortified foods were estimated; we used the latter to categorize participants by fortified food intake. RESULTS: Fortified foods were associated with significantly higher dietary intakes and biomarker status of folate, vitamin B-12, vitamin B-6, and riboflavin than were unfortified foods. There was no difference in natural food folate intake (range: 179-197 microg/d) between the fortified food categories. Red blood cell folate concentrations were 387 nmol/L higher and plasma total homocysteine concentrations were 2 micromol/L lower in the group with the highest fortified food intake (median intake: 208 microg/d folic acid) than in the nonconsumers of fortified foods (0 microg/d folic acid). CONCLUSIONS: These results show that voluntary food fortification is associated with a substantial increase in dietary intake and biomarker status of folate and metabolically related B vitamins with potential beneficial effects on health. However, those who do not consume fortified foods regularly may have insufficient B vitamin status to achieve the known and potential health benefits.     

Proposed vitamin a fortification levels

Fortified complementary foods could be effective in preventing and controlling vitamin A and other common nutritional deficiencies in young children. Milk from well-nourished women is an excellent source of vitamin A. However, in Latin America many children are weaned prematurely and must receive the entire requirement of vitamin A from food. This paper proposes vitamin A fortification levels for foods targeted for children aged 6-23 mo to meet the existing intake gap among both breast-fed and weaned infants and young children. Estimates assume a nonsignificant contribution of common complementary foods and average levels of human milk intake by breast-fed infants and children. The estimated vitamin A gap for breast-fed infants aged 6-11 mo amounts to 63-92 microg RE [16-23% of recommended daily intake (RDI)] and for breast-fed children reaches 125 microg RE (31% of RDI). Weaned infants and children would have to fully meet the RDI (400 microg RE) from complementary foods. A fortified complementary food with 500 mg RE/100 g of dry product provided daily in a single ration of 40 g would meet 50% of the gap for weaned infants aged 6-11 mo and would raise the total intake above RDI for breast-fed infants aged 6-8 mo (125%) and 9-11 mo (127%). The same fortified food given in a daily ration of 60 mg would meet most of the gap (75%) for weaned children aged 12-23 mo and would increase total intake of breast-fed children aged 12-23 mo well above the RDI (144%), with no risk of exceeding established upper tolerable intake levels.     

Vitamin D intake: a global perspective of current status

Global high prevalence of vitamin D insufficiency and re-emergence of rickets and the growing scientific evidence linking low circulating 25-hydroxyvitamin D to increased risk of osteoporosis, diabetes, cancer, and autoimmune disorders have stimulated recommendations to increase sunlight (UVB) exposure as a source of vitamin D. However, concern over increased risk of melanoma with unprotected UVB exposure has led to the alternative recommendation that sufficient vitamin D should be supplied through dietary sources alone. Here, we examine the adequacy of vitamin D intake worldwide and evaluate the ability of current fortification policies and supplement use practices among various countries to meet this recommendation. It is evident from our review that vitamin D intake is often too low to sustain healthy circulating levels of 25-hydroxyvitamin D in countries without mandatory staple food fortification, such as with milk and margarine. Even in countries that do fortify, vitamin D intakes are low in some groups due to their unique dietary patterns, such as low milk consumption, vegetarian diet, limited use of dietary supplements, or loss of traditional high fish intakes. Our global review indicates that dietary supplement use may contribute 6-47% of the average vitamin D intake in some countries. Recent studies demonstrate safety and efficacy of community-based vitamin D supplementation trials and food staple fortification introduced in countries without fortification policies. Reliance on the world food supply as an alternative to UVB exposure will necessitate greater availability of fortified food staples, dietary supplement use, and/or change in dietary patterns to consume more fish.     

Vitamins and minerals: A model for safe addition to foods

BACKGROUND: Significant subgroups in most European populations have intakes below nationally recommended levels for several vitamins, minerals and trace elements, placing individuals at risk of suboptimal intake of important vitamins and minerals. The voluntary addition of micronutrients to the appropriate foods may help address the risks associated with low micronutrient intakes. However, concerns need to be addressed regarding the potential for unacceptably high intakes, particularly for those people consuming very large amounts of food. AIM OF THE STUDY: To develop a model to estimate the level of each micronutrient that can be added safely to foods. METHODS: A theoretical model was developed based on the critical factors which determine the risk of unacceptably high intake for each micronutrient at high levels of food/energy intakes. These included 1) Tolerable Upper Intake Levels (UL), 2) high micronutrient intakes in Europe at the 95(th) percentile intake for each nutrient, 3) the proportion of fortified foods in the diets of individuals at the 95(th) percentile for energy intakes, 4) the proportion of foods to which micronutrients could practically be added, and 5) a range of estimates for the fractions of foods which might be actually fortified for each nutrient. A maximum level was set up for each micronutrient per typical serving or 100 kcal portion. The outputs of the model were then compared against a recent model developed by AFSSA, based on the food intake data in France. RESULTS: Three categories of micronutrients were identified, in which micronutrients could be added safely to foods at levels (per serving, e. g., 100 kcal) 1) greater than 1 European Commission Recommended Daily Intake (EC RDA): vitamin B12, vitamin C, vitamin E, riboflavin, panthothenic acid, niacin and thiamine; 2) between 50 and 100 % of the EC RDA: vitamin B6, vitamin D, folic acid, biotin, copper, iodine and selenium; 3) between 10 and 40 % of the EC RDA: iron, zinc, calcium, phosphorus and magnesium. A fourth category consisting of retinol, for which high end intake levels are close to UL for some population subgroups in Europe and thus requires further consideration. CONCLUSIONS: A wide range of vitamins and minerals can be added safely to foods at nutritionally important levels in the current diets of Europeans.     

Vitamin D intake of Dutch infants from the combination of (fortified) foods,infant formula,and dietary supplements

Purpose

Due to changes in the Dutch fortification policy for vitamin D and the vitamin D supplementation advice for infants (10-μg/d for 0–4 year olds), a partially virtual scenario study was conducted to evaluate the risk of excessive vitamin D intake assigning all infants to a 100 % adherence to the supplementation advice and considering the current fortification practice.

Methods

Food consumption data from the Nutrition Intake Study (2002; N = 941, 7–19 months) were combined with Dutch food composition data from 2011 to estimate vitamin D intake from (fortified) foods. For infants 0–6 months of age, the consumption volume infant formula was estimated from energy requirement and body weight. All subjects were assigned to take a daily 10 µg vitamin D supplement, according the Dutch supplementation advice for infants. Habitual vitamin D intake was estimated using the Statistical Program to Assess Dietary Exposure and compared with the tolerable upper intake levels (ULs) set by the European Food Safety Authority.

Results

The median habitual total vitamin D intake was 16–22 µg/day for infants aged 0–6 months (increasing with age) and 13–21 µg/day for infants aged 7–19 months (decreasing with age). About 4–12 % of infants aged 7–11 months exceeded the UL. At the 99th percentile, the intake was 2–4 µg above the UL, depending on age. Infants aged 0–6 and 12–19 months did not exceed the UL.

Conclusions

In case of combined intake from infant formula, (fortified) foods, and supplements, vitamin D intakes above the UL are possible among some infants during a limited time period.

     

Vitamin intake in Japanese women college students

The Standard Food Tables of Japanese Foods was newly revised in 2000, and contains information on all of the vitamins except biotin. Thus, we carried out a survey of vitamin intake in Japanese women who were university seniors majoring a dietitian course. The subjects (n = 33) consumed self-selected foods, and food intake was recorded by the weight method. We calculated the vitamin intake except for biotin from the food records using the Standard Food Tables of Japanese Foods. In terms of daily intake, vitamin A was 705+/-435 microg (mean+/-SD), vitamin D 6+/-8 microg, vitamin E 7.7+/-3.0 mg, vitamin K 191+/-156 microg, vitamin B1 0.7+/-0.3 mg (0.43+/-0.15 mg/1,000 kcal), vitamin B2 1.1+/-0.4 mg (0.65+/-0.18 mg/1,000 kcal), vitamin B6 0.9+/-0.4 mg (0.017+/-0.005 mg/g protein), vitamin B12 4.4+/-4.1 microg, niacin equivalent 23+/-7 mg (14.4+/-4.9 mg/1,000 kcal), pantothenic acid 4.6+/-1.4 mg, folic acid 267+/-115 microg, and vitamin C 73+/-38 mg. All of these averages were around the Japanese Recommended Dietary Allowance (RDA) for level "III (preferable)" of physical activity. Major vitamin A resources were vegetables; vitamin D resources, fish; vitamin E resources, fats and oils and vegetables; vitamin K resources, vegetables; vitamin B1 resources, cereals and animal meats; vitamin B2 resources, various foods; vitamin B6 resources, cereals, vegetables, fish, and animal meats; vitamin B12 resources, fish; niacin equivalent resources, fish, animal meats, and cereals; pantothenic acid resources, various foods; folic acid resources, vegetables; and vitamin C resources, vegetables and potatoes. From this survey, it was found that Japanese women college students consumed many kinds of food, and therefore, their vitamin nutrition was good as compared to the RDA values for level III of physical activity; however, their energy intake (1,622+/-377 kcal) was lower than the RDA for level III (2,050 kcal/d). Their strength of physical activity would be level I. Therefore, in consideration of their lifestyle, their energy intakes is considered adequate. In conclusion, a problem for student lifestyle is a shortage of food intake due to lack of exercise.     

Adequate Vitamin D Intake Cannot Be Achieved within Carbon Emission Limits Unless Food Is Fortified: A Simulation Study

This study applied linear programming using a Dutch “model diet” to simulate the dietary shifts needed in order to optimize the intake of vitamin D and to minimize the carbon footprint, considering the popularity of the diet. Scenarios were modelled without and with additional fortified bread, milk, and oil as options in the diets. The baseline diet provided about one fifth of the adequate intake of vitamin D from natural food sources and voluntary vitamin D-fortified foods. Nevertheless, when optimizing this diet for vitamin D, these food sources together were insufficient to meet the adequate intake required, unless the carbon emission and calorie intake were increased almost 3-fold and 2-fold, respectively. When vitamin D-fortified bread, milk, and oil were added as options to the diet, along with increases in fish consumption, and decreases in sugar, snack, and cake consumption, adequate intakes for vitamin D and other nutrients could be met within the 2000 kcal limits, along with a relatively unchanged carbon footprint. Achieving vitamin D goals while reducing the carbon footprint by 10% was only possible when compromising on the popularity of the diet. Adding vitamin D to foods did not contribute to the total carbon emissions. The modelling study shows that it is impossible to obtain adequate vitamin D through realistic dietary shifts alone, unless more vitamin D-fortified foods are a necessary part of the diet.     

Appropriate calcium fortification of the food supply presents a challenge

Fortification with calcium to increase dietary intakes of this mineral is currently under evaluation in Canada. To model the potential dietary consequences of food fortification, data from a large national survey of Canadians (n = 1543) were used. Food fortification scenarios were based on reference amounts for labeling requirements. Consumption of milk, cheese and other dairy products was associated with high calcium intakes, and there was a low prevalence of inadequacy in men < 50 y old; however, other age-sex groups had lower intakes. The aim of the fortification modeling was to determine which scenario would most effectively reduce the proportion of the population with low intakes of calcium while minimizing the proportion of individuals who exceeded the tolerable upper intake level (UL). Given the correlation between energy and calcium (r = 0.60, P < 0.01), it appeared that any fortification scenario sufficient to increase the mean intake for women to near the adequate intake led to 6-7% of the men having calcium intakes above the UL. The results suggest that fortification of widely consumed foods is not a realistic way to address the issue of low calcium intakes and illustrate the need for concern about the growing use of fortification practices.     

Intake of vitamin D by Finnish children aged 3 months to 3 years in relation to sociodemographic factors

OBJECTIVE: To study the total daily intake of vitamin D from food and supplements among Finnish children aged 3 months to 3 years, the dietary sources of vitamin D and the association between vitamin D intake and sociodemographic factors. SUBJECTS AND METHODS: The subjects are participants in the Finnish Type I Diabetes Prediction and Prevention Nutrition Study born between October 1997 and October 1998. At the age of 3 and 6 months, 1, 2 and 3 years, 342 (72% of the invited families), 298 (63%), 267 (56%), 233 (49%) and 209 (44%) families, respectively, participated in the present study. Food consumption was assessed by a 3-day food record. A structured questionnaire was used to record the parents' socioeconomic status. RESULTS: The mean dietary vitamin D intake exceeded the recommendation (10 microg/day) at the age of 3 (11.0 microg) and 6 months (12.0 microg), but decreased thereafter being 9.8, 5.0 and 4.1 microg at 1, 2 and 3 years of age, respectively. Among the children 91, 91, 81, 42 and 26% used vitamin D supplements at the age of 3 and 6 months, and 1, 2 and 3 years, respectively. In children not using vitamin D supplements, vitamin D intake was less than 10 microg/day at all ages. Vitamin D intake from food did not differ in children who used and did not use vitamin D supplements. Vitamin D supplements were the main source of vitamin D intake in all age groups studied, followed by vitamin D-fortified infant formula in 3-month-olds and infant formula and baby foods in 6-month-olds. After the age of 1 year, the most important food sources of vitamin D were margarine, fish, baby foods, low-fat milk and eggs. Sociodemographic factors, especially the number of children in the family and maternal age, were associated with the total vitamin D intake and vitamin D supplement use. CONCLUSION: Vitamin D supplements are not used according to the dietary recommendations in a substantial proportion of Finnish children.     

The impact of fortified foods on total dietary consumption in Europe

Summary   Foods can have nutrients added to restore those lost during preparation, to allow for substitution by different foods (for example the low level fortification of table margarine with vitamins A and D to replace these vitamins which are normally in butter but not in unfortified margarine), or to provide enriched foods. The objective of this study was to estimate the proportion of the total food consumed that is fortified in selected European countries (France, Germany, Italy, Spain and the UK). The data on per capita consumption of 44 food and drink categories was collated from commercial sources and surveys in France and the UK. The percentage of each food category which is fortified has been estimated. Data indicate that overall about 75% of food and drink consumed in European diets is rarely or never fortified. Fortified foods rarely contribute more than 3% of the total diet on a per capita basis, an exception being in countries where it is mandatory to fortify staple food ( e.g. as in the case of flour in the UK). High level consumers of fortified foods are unlikely to obtain more than 10% of their diet in a fortified form.     

Folate fortification: potential impact on folate intake in an older population

OBJECTIVE: To examine the potential impact of different models of folate fortification of Australian foods on the folate intakes of older Australians. DESIGN: Dietary data were collected using a food frequency questionnaire from people attending a population-based health study. SETTING: Two postcode areas west of Sydney, Australia. SUBJECTS: A total of 2895 people aged over 49 y, obtained from a door knock census (79% of 3654 subjects examined). MAIN OUTCOME MEASURES: The folate intake in this population was estimated using four different models: (1) pre-fortification folate values; (2) current voluntary folate fortification in Australia; (3) universal fortification of all foods permitted to add folate, at 25% recommended dietary intake (RDI) per reference serve; and (4) universal fortification of all foods permitted to add folate, at 50% RDI per reference serve. The increased bioavailability of synthetic folic acid (SFA) was included in the analysis. RESULTS: At current voluntary folate fortification, approximately 65% of this population consume 320 microg dietary folate equivalents (DFE) or more per day from diet and supplements, and 0.4% (n=10) consume greater than the recommended upper safety level of 1000 microg from SFA. More than 95% of this older population would be expected to consume more than 320 microg DFE from diet and supplements with universal fortification at 50% of the RDI, and 0.5% (n=14) may consume greater than 1000 microg/day of SFA. CONCLUSIONS: There is unlikely to be a large increase in the proportion of older persons who are likely to consume more than the upper safety level of intake with universal folate fortification. As most of those who currently or are predicted to consume over 1000 microg SFA take supplements containing folic acid, it is highly recommended that vitamin B12 be included in any vitamin supplements containing folate. SPONSORSHIP: This study was supported by the Australian National Health and Medical Research Council (NHMRC).     

The contribution of enrichment and fortification to nutrient intake of women

A volunteer group of 162 women aged 25 to 49 years was recruited from three suburban supermarkets in central New York state. The women completed 3-day food records, which were analyzed for total nutrient intake and contribution of eight nutrients from three sources: (a) nutrients naturally present in food, (b) enriched/fortified foods with a standard of identity (FF + SI), and (c) fortified foods without standards of identity (FF-SI). Subjects were placed into study groups of high-, moderate-, and low-fortifiers on the basis of frequency of intake of highly fortified foods (FF-SI) which, unlike FF + SI, are not staple foods and may represent selective dietary nutrient addition by the consumer. For all groups, mean intakes of riboflavin, niacin, and vitamins A and C were greater than 100% of the RDAs without nutrient addition. Mean thiamin intake met the RDA only when the nutrient addition from FF + SI was included. Mean intakes of iron, calcium, and vitamin D were all below the RDA even when all sources of intake were included. No significant differences between study groups were found for total nutrient intake. With the exceptions of vitamin C, vitamin D, and calcium, high- and moderate-fortifiers had significantly greater (p less than .01) nutrient intake from fortification. Low-fortifiers had significantly greater (p less than .05) intake from naturally occurring vitamins A and C than high-fortifiers.     

Assessment of vitamin D and vitamin A intake by female students at the United Arab Emirates University based on self-reported dietary and selected fortified food consumption

In the United Arab Emirates (UAE), many adolescent girls and women (especially the UAE citizens) are not adequately exposed to sunlight and their dietary intake of vitamin D is insufficient to fulfill the required recommended daily allowance of the vitamin. In the present study, the problem of vitamin D and vitamin A insufficiency in female students of UAE University was investigated through a dietary intake assessment of the vitamins. Results indicated that over 70% of female students constituting the survey population did not consume enough milk and other vitamin-D-rich foods, and many showed poor food habits. Prevalence of vitamin D insufficiency among the population studied indicated that 37% of the total population was considered vitamin D insufficient and 40% of the female students residing in the hostels also had vitamin D insufficiency ( < 5 μg/day) based on self-reported dietary and selected fortified food consumption.     

Assessment of vitamin D and vitamin A intake by female students at the United Arab Emirates University based on self-reported dietary and selected fortified food consumption

In the United Arab Emirates (UAE), many adolescent girls and women (especially the UAE citizens) are not adequately exposed to sunlight and their dietary intake of vitamin D is insufficient to fulfill the required recommended daily allowance of the vitamin. In the present study, the problem of vitamin D and vitamin A insufficiency in female students of UAE University was investigated through a dietary intake assessment of the vitamins. Results indicated that over 70% of female students constituting the survey population did not consume enough milk and other vitamin-D-rich foods, and many showed poor food habits. Prevalence of vitamin D insufficiency among the population studied indicated that 37% of the total population was considered vitamin D insufficient and 40% of the female students residing in the hostels also had vitamin D insufficiency ( < 5 μg/day) based on self-reported dietary and selected fortified food consumption.     

Barriers to optimizing vitamin D3 intake for the elderly

Available data on metabolic utilization of vitamin D3 indicate a total daily requirement of approximately 4000 international units (iu) (100 microg) or twice the current tolerable upper intake level (UL). In young individuals, most of this comes from the skin. However, cutaneous vitamin D3 synthesis declines with age, creating a need for increasing oral intake to maintain optimal serum 25-hydroxyvitamin D [25(OH)D] concentrations. Estimates of the population distribution of serum 25(OH)D values, coupled with available dose-response data, indicate that it would require input of an additional 2600 iu/d (65 microg/d) of oral vitamin D3 to ensure that 97.5% of older women have 25(OH)D values at or above desirable levels. The age-related decline in cutaneous input, taken together with the UL, creates a substantial barrier to the deployment of public health strategies to optimize vitamin D status in the elderly.