We quantified the prevalence of vitamin D status in 6–24-month-old underweight and normal-weight children and identified the socio-economic and dietary predictors for status.

Cross-sectional, baseline data from a nutritional intervention study were analysed. Multinomial logistic regression was used to estimate the odds of being vitamin D deficient or insufficient with the reference being vitamin D sufficient.

Urban slum area of Mirpur field site, Dhaka, Bangladesh.

Underweight (weight-for-age Z-score <−2·00) and normal-weight (weight-for-age Z-score ≥−1·00) children aged 6–24 months.

Among 468 underweight children, 23·1 % were sufficient, 42·3 % insufficient, 31·2 % deficient and 3·4 % severely vitamin D deficient. Among 445 normal-weight children, 14·8 % were sufficient, 39·6 % insufficient and 40·0 % deficient and 5·6 % severely deficient. With adjusted multinominal regression analysis, risk factors (OR (95 % CI)) for vitamin D deficiency in underweight children were: older age group (18–24 months old; 2·9 (1·5–5·7)); measurement of vitamin D status during winter (3·0 (1·4–6·4)) and spring (6·9 (3·0–16·1)); and maternal education (≥6 years of institutional education; 2·2 (1·0–4·9)). In normal-weight children, older age group (3·6 (1·2–10·6)) and living in the richest quintile (3·7 (1·1–12·5)) were found to be significantly associated with vitamin D insufficiency.

The study demonstrates a significant burden of vitamin D insufficiency and deficiency in both underweight and normal-weight children <2 years of age from an urban slum of Bangladesh. Identification of risk factors may help in mitigating the important burden in such children.

To assess vitamin D status and the influence of risk factors such as skin pigmentation and time spent outdoors on hypovitaminosis D among Guatemalan Kekchi and Garifuna adolescents.

Cross-sectional study, with convenient sampling design. Blood samples, anthropometric and behavioural data were all collected during the dry season. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured by RIA.

Communities of Rio Dulce and Livingston, Izabal Province, Caribbean coast of Guatemala, with latitude and longitude of 15°49′N and 88°45′W for Livingston and 15°46′N and 88°49′W for Rio Dulce, respectively.

Eighty-six adolescents, divided evenly by sex and ethnicity, with mean age of 14 years.

Mean (sd) 25(OH)D value was 27·8 (7·2) ng/ml for the total group, with 25·8 (5·9) and 29·8 (7·9) ng/ml, respectively, in Kekchis and Garifunas (P=0·01). Use of vitamin D supplementation, clothing practices and sun protection were not statistically different between groups. Skin area exposed on the day of data collection ranged from 20·0 % minimum to 49·4 % maximum, with mean (sd) exposure of 32·0 (8.5) %. With univariate regression analysis, age (P=0·034), sex (P=0·044), ethnicity (P=0·010), time spent outdoors (P=0·006) and percentage skin area exposed (P=0·001) were predictive. However, multivariate analysis indicated that only sex (P=0·034) and percentage skin area exposed (P=0·044) remained as predictors of 25(OH)D.

Despite residing in an optimal geographic location for sunlight exposure, nearly 65 % of study adolescents were either insufficient or deficient in vitamin D. Correction and long-term prevention of this nutritional problem may be instrumental in avoiding adverse effects in adulthood attributed to low 25(OH)D during adolescence.

To measure the trends in traditional marine food intake and serum vitamin D levels in Alaska Native women of childbearing age (20–29 years old) from the 1960s to the present.

We measured a biomarker of traditional food intake, the δ15N value, and vitamin D level, as 25-hydroxycholecalciferol (25(OH)D3) concentration, in 100 serum samples from 20–29-year-old women archived in the Alaska Area Specimen Bank, selecting twenty-five per decade from the 1960s to the 1990s. We compared these with measurements of red-blood-cell δ15N values and serum 25(OH)D3 concentrations from 20–29-year-old women from the same region collected during the 2000s and 2010s in a Center for Alaska Native Health Research study.

The Yukon Kuskokwim Delta region of south-west Alaska.

Alaska Native women (n 319) aged 20–29 years at the time of specimen collection.

Intake of traditional marine foods, as measured by serum δ15N values, decreased significantly each decade from the 1960s through the 1990s, then remained constant from the 1990s through the present (F5,306=77·4, P<0·0001). Serum vitamin D concentrations also decreased from the 1960s to the present (F4,162=26·1, P<0·0001).

Consumption of traditional marine foods by young Alaska Native women dropped significantly between the 1960s and the 1990s and was associated with a significant decline in serum vitamin D concentrations. Studies are needed to evaluate the promotion of traditional marine foods and routine vitamin D supplementation during pregnancy for this population.

To evaluate vitamin D deficiency prevalence and risk factors among pregnant Chinese women.

A descriptive cross-sectional analysis.

China National Nutrition and Health Survey (CNNHS) 2010–2013.

A total of 1985 healthy pregnant women participated. Possible predictors of vitamin D deficiency were evaluated via multiple logistic regression analyses.

The median serum 25-hydroxyvitamin D level was 15·5 (interquartile range 11·9–20·0, range 3·0–51·5) ng/ml, with 74·9 (95 % CI 73·0, 76·7) % of participants being vitamin D deficient (25-hydroxyvitamin D <20 ng/ml). According to the multivariate logistic regression analyses, vitamin D deficiency was positively correlated with Hui ethnicity (P=0·016), lack of vitamin D supplement use (P=0·021) and low ambient UVB level (P<0·001). In the autumn months, vitamin D deficiency was related to Hui ethnicity (P=0·012) and low ambient UVB level (P<0·001). In the winter months, vitamin D deficiency was correlated with younger age (P=0·050), later gestational age (P=0·035), higher pre-pregnancy BMI (P=0·019), low ambient UVB level (P<0·001) and lack of vitamin D supplement use (P=0·007).

Vitamin D deficiency is prevalent among pregnant Chinese women. Residing in areas with low ambient UVB levels increases the risk of vitamin D deficiency, especially for women experiencing advanced stages of gestation, for younger pregnant women and for women of Hui ethnicity; therefore, vitamin D supplementation and sensible sun exposure should be encouraged, especially in the winter months. Further studies must determine optimal vitamin D intake and sun exposure levels for maintaining sufficient vitamin D levels in pregnant Chinese women.

To document the effect of season and environmental pollution on UVB irradiance; and to estimate cutaneous vitamin D synthesis in village women in different seasons.

Radiant UVB energy was measured by a spectroradiometer in different seasons and, in April and May, on successive days in open areas at the city outskirts, at a crowded inner-city area and the villages of our participants. Clothing, outdoor activity pattern and serum 25-hydroxycholecalciferol (25(OH)D) levels were documented.

Rural north India, latitude 26·8°N.

Pregnant women (n 139, aged 20–40 years).

UVB irradiance ranged from 56 µW/cm2 in January to 470 µW/cm2 in June. Proportion of skin exposed was 18·5 % in summer and 9·5 % in winter. Mean (sd) daily duration of sun exposure was 3·2 (0·2) h during winter and 2·1 (0·4) h during summer. Cutaneous vitamin D synthesis was estimated to be 19·25 µg (770 IU) during winter and 37·25 µg (1490 IU) during summer. Mean (sd) serum 25(OH)D was 28 (15) nmol/l during winter (92 % of participants with <50 nmol/l) and reached 56 (20) nmol/l during late summer (60 % with >50 nmol/l). Mean (sd) UVB irradiance at peak summer was significantly higher at the open areas and in the villages than at the inner-city location (340 (45) and 310 (60) v. 250 (50) µW/cm2, P=0·03).

In our population, at latitude 26·8°N, poor skin exposure is a limiting factor in all seasons. During winter, low UVB radiation energy also contributes. Particulate pollution limits UVB irradiance. Vitamin D supplementation during winter may be necessary.

To identify the relationship between perceptions of Ca and vitamin D consumption and actual intakes to inform the design of osteoporosis prevention education.

An FFQ was used to approximate usual monthly Ca and vitamin D intakes among a group of young Canadians. Qualitative interviews and a food card pile sort activity explored individuals’ perceptions of nutrient intakes. The FFQ was used to assess nutrient adequacy for individual participants and the qualitative interviews and pile sort were analysed using thematic content analysis.

Hamilton, Canada.

Sixty participants aged 17–30 years, representing varying levels of educational attainment.

Seventy-eight per cent of young adults who consumed inadequate vitamin D perceived their intake as adequate, compared with 57 % for Ca. Thematic analysis revealed three major themes that contributed to young adults’ understandings of intake: belief their diet was correct, absence of symptoms and confusion over nutrient sources.

The majority of participants perceived themselves as consuming adequate amounts of Ca and vitamin D, when they were actually consuming inadequate amounts according to FFQ findings. These perceptions were related to low engagement in prevention activities. Prevention education must motivate young adults to question the adequacy of their micronutrient intakes and design tailored programmes that are geared to a young adult audience.

To determine the prevalence of vitamin D supplement use in Canadian adults and associations with demographic and socio-economic variables.

Data from the Healthy Aging module of the Canadian Community Health Survey were used to investigate the prevalence of vitamin D supplement use in Canadians aged 45 years and over. The prevalence of supplement use stratified by various behavioural and demographic characteristics was calculated and adjusted models were used to find associations with those factors.

The ten provinces of Canada.

Canadians aged 45 years and over who participated in the Healthy Aging module of the Canadian Community Health Survey from 2008–2009.

The highest observed prevalence for women was 48·0 % in the 65–69 years age group and the highest prevalence for men was 25·3 % in the 70–74 years age group. Women had higher odds of vitamin D supplement use than men in all age groups. Not using supplements was more common in smokers, those who did not engage in leisure-time physical activities and who were either overweight or obese. Vitamin D supplement use increased with household income and level of education, and decreased with self-perceived health. Supplement use was higher in those with chronic conditions.

The inverse association with self-perceived health could be partly explained by age, chronic conditions and increased use of health-care services. Associations with higher income and education suggest a strong socio-economic influence and that individuals may not have the expendable income to purchase vitamin D supplements or knowledge of their health benefits.

To investigate relationships between mortality and circulating 25-hydroxyvitamin D (25(OH)D), 25-hydroxycholecalciferol (25(OH)D3) and 25-hydroxyergocalciferol (25(OH)D2).

Case–cohort study within the Melbourne Collaborative Cohort Study (MCCS). We measured 25(OH)D2 and 25(OH)D3 in archived dried blood spots by LC–MS/MS. Cox regression was used to estimate mortality hazard ratios (HR), with adjustment for confounders.

General community.

The MCCS included 29 206 participants, who at recruitment in 1990–1994 were aged 40–69 years, had dried blood spots collected and no history of cancer. For the present study we selected participants who died by 31 December 2007 (n 2410) and a random sample (sub-cohort, n 2996).

The HR per 25 nmol/l increment in concentration of 25(OH)D and 25(OH)D3 were 0·86 (95 % CI 0·78, 0·96; P=0·007) and 0·85 (95 % CI 0·77, 0·95; P=0·003), respectively. Of 5108 participants, sixty-three (1·2 %) had detectable 25(OH)D2; their mean 25(OH)D concentration was 11·9 (95 % CI 7·3, 16·6) nmol/l higher (P<0·001). The HR for detectable 25(OH)D2 was 1·80 (95 % CI 1·09, 2·97; P=0·023); for those with detectable 25(OH)D2, the HR per 25 nmol/l increment in 25(OH)D was 1·06 (95 % CI 0·87, 1·29; P interaction=0·02). HR were similar for participants who reported being in good, very good or excellent health four years after recruitment.

Total 25(OH)D and 25(OH)D3 concentrations were inversely associated with mortality. The finding that the inverse association for 25(OH)D was restricted to those with no detectable 25(OH)D2 requires confirmation in populations with higher exposure to ergocalciferol.

To examine the associations between serum 25-hydroxyvitamin D (25(OH)D), dietary Ca intake and presence of the metabolic syndrome (MetS).

A stratified cluster sample of a population aged 18–75 years from the Victorian Health Monitor survey.

Non-institutionalized adults living in private dwellings in Victoria, Australia.

Adults (n 3404) with complete data and without type 1 or type 2 diabetes.

Adjusted for sociodemographic factors, physical characteristics and dietary covariates including Ca intake, every 10 nmol/l increase in serum 25(OH)D was significantly associated with decreased odds of MetS (adjusted odds ratio (AOR)=0·85, 95 % CI 0·80, 0·89; P<0·001). Relative to the low 25(OH)D tertile (median 33 nmol/l), there was a progressive decrease in odds of MetS that reached significance with the high 25(OH)D tertile (median 77 nmol/l; AOR=0·35, 95 % CI 0·26, 0·48; P<0·001). Every 500 mg/d increase in Ca intake adjusted for 25(OH)D did not reduce odds of MetS (AOR=0·81, 95 % CI 0·66, 1·06; P=0·141) but approached significance if unadjusted for 25(OH)D in the final model (AOR=0·81, 95 % CI 0·64, 1·02; P=0·073). No significant effect was obtained for tertiles of Ca intake. However, Ca and vitamin D tertile combinations suggested a beneficial effect of high Ca (median 1233 mg/d) only at low and medium 25(OH)D. The high 25(OH)D tertile was associated with significantly decreased odds of MetS regardless of Ca intake.

A high vitamin D status significantly reduced the odds of MetS. A high Ca intake may have a similar favourable outcome but only at lower circulating concentrations of 25(OH)D.

To examine the interaction between waist circumference (WC) and serum 25-hydroxyvitamin D (25(OH)D) level in their associations with serum lipids.

Cross-sectional study. The associations of serum 25(OH)D with total cholesterol, HDL cholesterol (HDL-C), LDL cholesterol (LDL-C), LDL-C:HDL-C and TAG were examined using multiple linear regression. Effect modification by WC was assessed through cross-product interaction terms between 25(OH)D and WC categories (abdominal overweight, 80–<88 cm in females/94–<102 cm in males; abdominal obesity, ≥88 cm in females/≥102 cm in males).

The US National Health and Nutrition Examination Survey waves 2001–2006.

Non-pregnant fasting participants (n 4342) aged ≥20 years.

Lower 25(OH)D levels were significantly associated with lower HDL-C levels as well as with higher LDL-C:HDL-C and TAG levels in abdominally obese participants, but not in abdominally overweight or normal-waist participants. In contrast, lower 25(OH)D levels were associated with lower levels of total cholesterol and LDL-C in abdominally overweight and normal-waist participants only, but this association was only partly significant. However, a significant difference in the association between 25(OH)D and the lipids according to WC category was found only for LDL-C:HDL-C (P for interaction=0·02).

Our results from this large, cross-sectional sample suggest that the association between lower 25(OH)D levels and an unfavourable lipid profile is stronger in individuals with abdominal obesity than in those with abdominal overweight or a normal WC.

To assess vitamin D dietary sources, intake and 25-hydroxyvitamin D status and their association with individual and sociodemographic characteristics in Mexican children.

Data obtained from 2695 children aged 1–11 years from the Mexican National Health and Nutrition Survey (2012) were analysed. Diet was assessed by a 141-item FFQ. 25-Hydroxyvitamin D was measured by a chemiluminescent assay.

Mean vitamin D intake was 3·38 (se 0·09) µg/d (135·2 (se 3·6) IU/d) among pre-school children and 2·85 (se 0·06) µg/d (114·0 (se 2·4) IU/d) in school-age children. Milk accounted for 64·4 % of vitamin D intake in pre-school children and 54·7 % in school-age children. Vitamin D deficiency (serum 25-hydroxyvitamin D<50 nmol/l) was 25·9 % in pre-schoolers and 36·6 % in school-age children. Overweight/obese school-age children had a higher risk of vitamin D deficiency compared with normal-weight children (OR=2·23; 95 % CI 1·36, 3·66; P<0·05).

Vitamin D intakes are low in Mexican children, and milk is the main source of the vitamin. Vitamin D deficiency is common and associated with overweight in school-age children.

Upper respiratory tract infections (URTI) are the most common and costly condition of childhood. Low vitamin D levels have been hypothesized as a risk factor for URTI. The primary objective was to determine if serum vitamin D levels were associated with health-service utilization (HSU) for URTI including hospital admission, emergency department visits and outpatient sick visits. The secondary objectives were to determine whether oral vitamin D supplementation in pregnancy or childhood was associated with HSU for URTI.

Cohort study. HSU was determined by linking each child’s provincial health insurance number to health administrative databases. Multivariable quasi Poisson regression was used to evaluate the association between 25-hydroxyvitamin D, vitamin D supplementation and HSU for URTI.

Toronto, Canada.

Children participating in the TARGet Kids! network between 2008 and 2013.

Healthy children aged 0–5 years (n 4962) were included; 52 % were male and mean 25-hydroxyvitamin D was 84 nmol/l (range 11–355 nmol/l). There were 105 (2 %), 721 (15 %) and 3218 (65 %) children with at least one hospital admission, emergency department visit or outpatient sick visit for URTI, respectively. There were no statistically significant associations between 25-hydroxyvitamin D or vitamin D supplementation and HSU for URTI.

A clinically meaningful association between vitamin D (continuously and dichotomized at <50 and <75 nmol/l) and HSU for URTI was not identified. While vitamin D may have other benefits for health, reducing HSU for URTI does not appear to be one of them.

The objective of the present study was to determine if vitamin D intake and status are associated with pre-eclampsia in a country without a vitamin D fortification policy.

A case–control study of pregnancies with (case) and without (control) pre-eclampsia was conducted from January to April when UVB is minimal. Maternal and cord blood obtained at delivery were measured for plasma 25-hydroxycholecalciferol (25-OH-D3), 3-epimer of 25-OH-D3 (3-epi-25-OH-D3) and 24,25-dihydroxycholecalciferol (24,25-(OH)2D3) by LC–MS/MS and maternal 1,25-dihydroxyvitamin D (1,25-(OH)2D). Differences between groups were tested with ANOVA and Bonferroni post hoc tests (P<0·05).

Clinical Center of Serbia.

Pregnant women with and without pre-eclampsia (n 60) and their infants.

Exogenous vitamin D intake (0·95–16·25 µg/d (38–650 IU/d)) was not significantly different between groups. Women with pre-eclampsia delivered infants at an earlier gestational age and had significantly lower mean total plasma 25-hydroxyvitamin D (25-OH-D; case: 11·2 (sd 5·1); control: 16·1 (sd 5·7) ng/ml; P=0·0006), 25-OH-D3 (case: 10·0 (sd 4·9); control: 14·2 (sd 5·8) ng/ml; P=0·002), 3-epi-25-OH-D3 (case: 0·5 (sd 0·2); control: 0·7 (sd 0·2) ng/ml; P=0·0007) and 1,25-(OH)2D (case: 56·5 (sd 26·6); control: 81·0 (sd 25·7) pg/ml; P=0·018), while 24,25-(OH)2D3 was not different between groups. Infants did not differ in total plasma 25-OH-D, 25-OH-D3, 3-epi-25-OH-D3 and 24,25-(OH)2D3, but the mean proportion of 3-epi-25-OH-D3 was higher in the infant case group (case: 7·9 (sd 1·1); control: 7·0 (sd 1·4) % of total 25-OH-D3; P=0·005).

A high prevalence of vitamin D deficiency, as defined by plasma 25-OH-D<12 ng/ml, was observed in 47 % of all mothers and 77 % of all infants. These data underscore the need for prenatal vitamin D supplementation and a food fortification policy in Serbia.

To examine the hypothesis that the association between vitamin D deficiency and depressive symptoms is dependent upon total cholesterol level in a representative national sample of the South Korean population.

This was a population-based cross-sectional study.

The Fifth Korean National Health and Nutrition Examination Survey (KNHANES V, 2010–2012).

We included 7198 adults aged 20–88 years.

The incidence of depressive symptoms in individuals with vitamin D deficiency (serum 25-hydroxyvitamin D<20 ng/ml) was 1·54-fold (95 % CI 1·20, 1·98) greater than in individuals without vitamin D deficiency (serum 25-hydroxyvitamin D ≥20 ng/ml). The relationship was stronger in individuals with normal-to-borderline serum total cholesterol (serum total cholesterol<240 mg/dl; OR=1·60; 95 % CI 1·23, 2·08) and non-significant in individuals with high serum total cholesterol (OR=0·97; 95 % CI 0·52, 1·81) after adjustment for confounding variables (age, sex, BMI, alcohol consumption, smoking status, regular exercise, income level, education level, marital status, changes in body weight, perceived body shape, season of examination date and cholesterol profiles).

The association between vitamin D deficiency and depressive symptoms was weakened by high serum total cholesterol status. These findings suggest that both vitamin D and total cholesterol are important targets for the prevention and treatment of depression.

To determine the association of vitamin D status with depression and health-related quality of life among women.

This was a cross-sectional study conducted among women in Kuala Lumpur, Malaysia. Sociodemographic characteristics, physical activity status, perceived depression and health-related quality of life were assessed via a self-administered questionnaire. Fasting blood samples were taken for the analysis of 25-hydroxyvitamin D, parathyroid hormone, fasting blood glucose and full lipid profile. Complex samples multiple logistic regression analysis was performed.

Public secondary schools in Kuala Lumpur, Malaysia.

Seven hundred and seventy female teachers were included.

The mean age of participants was 41·15 (95 % CI 40·51, 41·78) years and the majority were ethnic Malays. Over 70 % of them had vitamin D deficiency (<20 ng/ml or <50 nmol/l) and two-thirds were at risk for depression. In the multivariate analysis, ethnic Malays (adjusted OR (aOR)=14·72; 95 % CI 2·12, 102·21) and Indians (aOR=14·02; 95 % CI 2·27, 86·59), those at risk for depression (aOR=1·88, 95 % CI 1·27, 2·79) and those with higher parathyroid hormone level (aOR=1·13; 95 % CI 1·01, 1·26) were associated with vitamin D deficiency, while vitamin D deficiency was negatively associated with mental health-related quality of life (Mental Component Summary) scores (aOR=0·98; 95 % CI 0·97, 0·99).

Vitamin D deficiency is significantly associated with depression and mental health-related quality of life among women in Kuala Lumpur, Malaysia.

To evaluate prevalence of vitamin D deficiency and its associated factors in southern Iranian children.

Cross-sectional study. Anthropometric and pubertal characteristics were assessed by a trained physician. Physical activity and sun exposure were evaluated using standard questionnaires. Body composition measurements were performed using dual-energy X-ray absorptiometry. Serum Ca, P alkaline phosphatase and 25-hydroxyvitamin D (25(OH)D) were assessed in all children. Statistical analysis was done using the statistical software package IBM SPSS Statistics 18·0.

Iranian children (n 477) aged 9–18 years.

Fars Province, Iran, 2011.

Of the children, 81·3 % were 25(OH)D deficient. There was no significant difference in 25(OH)D concentration between boys and girls (P=0·3). 25(OH)D concentration was associated with BMI (r=−0·1, P=0·02), pubertal status (r=−0·08, P=0·04) and sun exposure (r=0·10, P=0·04). Fat mass index was associated with 25(OH)D concentration (r=−0·13, P=0·03), but not lean mass index (P=0·86). In multiple regression analysis with adjustment for confounding factors, age and puberty were found to be independently associated with 25(OH)D concentration (P=0·008 and P=0·006); there was a significant correlation between exercise and 25(OH)D concentration after adjustment for either BMI (P=0·01) or fat mass index (P=0·02).

25(OH)D deficiency is highly prevalent among children in the south of Iran. It is related to insufficient sun exposure, low physical activity, advancing age and pubertal stage. Measures should be taken to improve the health of southern Iranian children in this critical age group by preventing 25(OH)D deficiency.

Current US dietary recommendations for vitamin D vary by age. Recent research suggests that body weight and skin colour are also major determinants of vitamin D status. The objective of the present epidemiological investigation was to clarify the role of age as a predictor of vitamin D status, while accounting for body weight and skin colour, among a nationally representative sample.

We calculated the mean serum 25-hydroxyvitamin D levels for the US population by age and weight, as well as by weight and race/ethnicity group. Multiple regression analyses were utilized to evaluate age and weight as predictors of vitamin D status: serum 25-hydroxyvitamin D levels with age alone, age and body weight, and age, body weight and their two-way interaction were modelled for the entire sample and each age subgroup. Graphical data were developed using B-spline non-linear regression.

National Health and Nutrition Examination Survey (31 934 unweighted cases).

Individuals aged 1 year and older.

There were highly significant differences in mean vitamin D status among US residents by weight and skin colour, with those having darker skin colour or higher body weight having worse vitamin D status. Although a significant factor, the impact of age on vitamin D status was notably less than the impact of body weight.

Vitamin D status varied predominantly by body weight and skin colour. Recommendations by nutritionists for diet and supplementation needs should take this into account if vitamin D-related health disparities are to be meaningfully reduced across the USA.

To determine the effect of prenatal maternal vitamin D supplementation on infant vitamin D status in a tropical region where vitamin D supplementation is not routine.

A prospective observational follow-up of a randomized trial.

Maternal–child health facility in Dhaka, Bangladesh (23°N).

Infants born to pregnant women (n 160) randomized to receive 875 µg (35 000 IU) cholecalciferol (vitamin D3) per week (VD) or placebo (PL) during the third trimester were followed from birth until 6 months of age (n 115). Infant serum 25-hydroxyvitamin D concentration (25(OH)D) was measured at <1, 2, 4 and 6 months of age.

Mean infant 25(OH)D was higher in the VD v. PL group at <1 month of age (mean (sd): 80 (20) nmol/l v. 22 (18) nmol/l; P<0·001), but the difference was attenuated by 2 months (52 (19) nmol/l v. 40 (23) nmol/l; P=0·05). Groups were similar at 4 months (P=0·40) and 6 months (n 72; P=0·26). In the PL group, mean infant 25(OH)D increased to 78 (95 % CI 67, 88) nmol/l by 6 months of age (n 34). 25(OH)D was higher with infant formula-feeding and higher in summer v. winter.

Prenatal third-trimester vitamin D supplementation (875 µg (35 000 IU)/week) significantly ameliorated infant vitamin D status during the neonatal period when the risk of vitamin D deficiency is greatest. Further research is warranted to determine factors that contribute to the rise in 25(OH)D during the first 6 months of life among breast-fed infants in this setting.

The study evaluates the economic benefit of population-wide vitamin D and Ca food fortification in Germany.

Based on a spreadsheet model, we compared the cost of a population-wide vitamin D and Ca food-fortification programme with the potential cost savings from prevented fractures in the German female population aged 65 years and older.

The annual burden of disease and the intervention cost were assessed for two scenarios: (i) no food fortification; and (ii) voluntary food fortification with 20 µg (800 IU) of cholecalciferol (vitamin D3) and 200 mg of Ca. The analysis considered six types of fractures: hip, clinical vertebral, humerus, wrist, other femur and pelvis.

Subgroups of the German population defined by age and sex.

The implementation of a vitamin D and Ca food-fortification programme in Germany would lead to annual net cost savings of €315 million and prevention of 36 705 fractures in the target population.

Vitamin D and Ca food fortification is an economically beneficial preventive health strategy that has the potential to reduce the future health burden of osteoporotic fractures in Germany. The implementation of a vitamin D and Ca food-fortification programme should be a high priority for German health policy makers because it offers substantial cost-saving potential for the German health and social care systems.