To describe vitamin D intakes in children and teenagers and the contribution from supplements and fortified foods in addition to the base diet.

Analysis of 7 d weighed food records collected during the Children's and Teens’ National Nutrition Surveys in Ireland. Food composition data for vitamin D were updated from international analytical sources.

Nationally representative cross-sectional dietary surveys.

Children (n 594; 5–12 years) and teenagers (n 441; 13–17 years).

Median vitamin D intakes were 1·9, 2·1 and 2·4 μg/d in 5–8-, 9–12- and 13–17-year-olds, respectively. The prevalence of vitamin D-containing supplement use was 21, 16 and 15 % in 5–8-, 9–12- and 13–17-year-olds and median intakes in users ranged from 6·0 to 6·7 μg/d. The prevalence of inadequate intakes, defined as the percentage with mean daily intakes below the Estimated Average Requirement of 10 μg/d, ranged from 88 to 96 % in supplement users. Foods fortified with vitamin D, mainly breakfast cereals, fat spreads and milk, were consumed by 71, 70 and 63 % of 5–8-, 9–12- and 13–17-year-olds. Non-supplement users who consumed vitamin D-fortified foods had median intakes of 1·9–2·5 μg/d, compared with 1·2–1·4 μg/d in those who did not consume fortified foods.

It is currently not possible for children consuming the habitual diet to meet the US Institute of Medicine dietary reference intake for vitamin D. In the absence of nationally representative 25-hydroxyvitamin D data in children, the implications of this observation for prevalence of vitamin D deficiency and health consequences are speculative.

High prevalence of hypovitaminosis D has been reported to be common in different regions of the Middle East. The objective of the present study was to examine the predictors of vitamin D deficiency and insufficiency in Bahrainis.

A cross-sectional study.

Blood transfusion volunteers at a blood bank.

Serum levels of total 25-hydroxyvitamin D, bone markers and other parameters such age, sex, season and clothing style in the 500 healthy Bahrainis were investigated.

In the entire cohort the prevalence of vitamin D deficiency was 49·4 % and the relative risk of vitamin D deficiency increased significantly by 1·1, 1·2, 1·5, 1·7 and 1·2 fold with younger age group (P = 0·03), hyperparathyroidism (P = 0·01), low serum Ca (P < 0·001), warm and hot months of the year (P < 0·0001) and female sex (P = 0·002), respectively. In females the prevalence of vitamin D deficiency was 67·6 % and the relative risk of vitamin D deficiency increased significantly by 1·1, 1·2, 1·2, 1·2 and 1·4 fold with younger age group (P = 0·04), hyperparathyroidism (P = 0·03), low serum Ca (P = 0·001), warm and hot months of the year (P = 0·001) and conservative clothing style (P = 0·04), respectively. In contrast, in males the prevalence of vitamin D deficiency was 31·2 % and the relative risk of vitamin D deficiency was increased by 1·6 fold in warm and hot months of the year (P < 0·0001).

High prevalence of low circulating levels of vitamin D and the relative risk factors associated with vitamin D deficiency and insufficiency observed in the present study suggest an urgent need for public health interventions including vitamin D food fortification in Bahrain.

Our objective was to determine whether a questionnaire can identify individuals with vitamin D insufficiency (VDI).

Women completed the Vitamin D & Sun (VIDSUN) questionnaire and we measured their serum 25-hydrocyvitamin D (25(OH)D) levels. We assessed the sensitivity and specificity of the questionnaire to identify VDI (25(OH)D level <50 nmol/l).

Clinical Research Unit, University of Wisconsin–Madison.

Postmenopausal women.

We recruited 609 postmenopausal women with a mean age of 61 (sd 6 years), of whom 113 (19 %) had VDI. Women with VDI were more likely to be black (17 % v. 2 %, P < 0·001), heavier (BMI 33·0 (sd 7) kg/m2v. 29·0 (sd 7) kg/m2, P < 0·001) and less likely to tan in the past year (49 % v. 72 %, P < 0·001), use sunscreen (57 % v. 72 %, P < 0·001) or report sun exposure in the last 3 months. They consumed less vitamin D from supplements (2·15 (sd 5·24) μg/d (86 (sd 210) IU/d) v. 4·55 (sd 8·48) μg/d (188 (sd 344) IU/d), P = 0·003). In logistic regression models, black race, BMI, suntan within the past year, sun exposure in the past 3 months, sunscreen use and supplemental vitamin D intake were the most useful questions to identify VDI. From these six items, a composite score of ≤2·25 demonstrated ≥89 % sensitivity but ≤35 % specificity for VDI.

The VIDSUN questionnaire provides an initial tool to identify postmenopausal women at high or low risk of VDI. Existing studies suggest that inclusion of physical activity and TAG levels might improve the performance of the VIDSUN questionnaire.

To assess the inter-method reliability of the Ovarian Cancer in Alberta (OVAL) survey developed to estimate adult vitamin D exposure from sun and diet for every tenth year, against the longer Geraldton Skin Cancer Prevention Survey (the assumed ‘gold standard’). We also estimated total vitamin D exposure using the OVAL survey.

A randomized crossover design to assess the inter-method reliability of sun exposure (OVAL v. Geraldton survey), using intra-class correlation and estimated total vitamin D exposure from sun and diet.

Calgary, Alberta, Canada.

Randomly selected women (n 90) aged 40–79 years.

The average lifetime sun exposure of 13 913 h (average 411 h/year) from the Geraldton survey was not significantly different from the 13 034 h (average 385 h/year) from the OVAL survey for periods with sufficient UV radiation to stimulate vitamin D production. The intra-class correlation coefficient for average lifetime sun exposure was 0·77 (95 % CI 0·69, 0·86); the annual average was 0·60 (95 % CI 0·47, 0·74). Estimated vitamin D from diet and supplements increased with age.

Our OVAL survey reliably estimated adult sun exposure relative to the Geraldton survey, suggesting that assessing sun exposure every tenth year is a reliable and efficient method for estimating sun contributions to lifetime vitamin D exposure.

To determine if dietary, supplemental and total vitamin D intakes in the USA are influenced by income, race/ethnicity or gender.

Cross-sectional. US vitamin D intakes were estimated by poverty income ratio (PIR), race/ethnicity and gender using 24 h dietary intake recalls and dietary supplement use questionnaires. Statistical analyses of weighted data were performed using SAS (version 9·2) to estimate means and their standard errors. Race and ethnic intake differences controlling for PIR, gender and age were assessed by ANCOVA.

Adults aged ≥19 years.

The 2007–2010 National Health and Nutrition Examination Survey, USA.

Total (dietary and supplement) vitamin D intake was greater in the high (10·0 (se 0·30) μg/d) v. the medium (7·9 (se 0·3) μg/d) or the low (8·0 (se 0·3) μg/d) PIR categories. Total vitamin D intake of non-Hispanic Whites (10·6 (se 0·4) μg/d) was greater than that of Hispanics (8·1 (se 0·3) μg/d) and non-Hispanic Blacks (7·1 (se 0·3) μg/d). Supplemental vitamin D intake was greater by females (5·3 (se 0·2) μg/d) than by males (3·3 (se 0·2) μg/d). Participants with high income were more likely to be vitamin D supplement users (33·0 %) than those with medium (22·5 %) or low (17·6 %) income. High-income non-Hispanic Whites had the lowest percentage (57 %) not meeting the Estimated Average Requirement for vitamin D. Fortified milk and milk products provided 43·7 % of the dietary vitamin D intake.

Public health efforts should expand the number of vitamin D-fortified foods and encourage the consumption of foods high in vitamin D and use of supplements.

To evaluate the prevalence of vitamin D deficiency and predictors for low vitamin D status in Korean adolescents living between latitudes 33° and 39°N.

A descriptive cross-sectional study.

Korea National Health and Nutrition Examination Survey (KNHANES) 2008–2009.

A total of 1510 healthy adolescents aged 12–18 years (806 male, mean age 14·7 years) participated. Possible predictors for low vitamin D status (log-transformed 25-hydroxyvitamin D (25(OH)D) concentrations) were evaluated.

The prevalence of vitamin D deficiency (25(OH)D<20 ng/ml) was 89·1 % in spring, 53·7 % in summer, 63·9 % in autumn and 90·5 % in winter. Winter season, older age, higher education level reached, being female, being obese, a lack of vitamin D supplementation, lower milk consumption (0–<200 ml/d) and a lack of physical activity were unadjusted predictors (all P < 0·05). Multiple linear regression analysis showed that winter season (P < 0·001), higher education level (P < 0·001) and a lack of vitamin D supplementation (P = 0·012) were independent predictors for low vitamin D status. The modifying effect of season on the association between vitamin D supplement use and vitamin D status was significant (P < 0·001).

Vitamin D deficiency was highly prevalent in Korean adolescents, especially those in higher school grades. Vitamin D supplementation may contribute to maintain a better vitamin D status with lower seasonal variation. Further studies are required to determine optimal vitamin D intakes to maintain sufficient vitamin D status for Korean adolescents.

In 2011, the US Institute of Medicine updated the definition of vitamin D inadequacy to serum 25-hydroxyvitamin D (25(OH)D) concentration of 30–<50 nmol/l and of deficiency to serum 25(OH)D < 30 nmol/l. We describe the prevalence of these conditions according to these definitions, seasonal variation in 25(OH)D and predictors of serum 25(OH)D concentrations among working, white women.

Participants recorded lifestyle factors and dietary intake and provided fasting blood samples for measurement of serum 25(OH)D in both summer and winter. Predictors of serum 25(OH)D variation were analysed using linear regression and generalized linear mixed models.

Kingston General Hospital in Kingston, Ontario, Canada, from April 2008 to July 2009.

Female premenopausal nurses (n 83) working full-time rotating shifts.

Deficient or inadequate vitamin D status was observed in 9 % of participants following summer/autumn and in 13 % following winter/spring. Predictors of serum 25(OH)D concentration were vitamin D supplement use, tanning bed use and season. Tanning bed use increased serum 25(OH)D by 23·24 nmol/l (95 % CI 8·78, 37·69 nmol/l, P = 0·002) on average.

According to the 2011 Institute of Medicine bone health guidelines, over 10 % of nurses had deficient or inadequate vitamin D status following winter. Higher serum concentrations were associated with use of tanning beds and vitamin D supplements. As health promotion campaigns and legal restrictions are successful in reducing tanning bed use among women, our data suggest that increased prevalence of vitamin D inadequacy and deficiency may be a consequence, and that low vitamin D status will need to be countered with supplementation.

Previous studies have suggested anti-infection effects of vitamin D, although the associations reported between vitamin D (serum 25-hydroxyvitamin D (25(OH)D) concentration) and respiratory tract infection (RTI) are conflicting. The main aim of the present study was to explore this association in a Norwegian population.

We examined the association between serum 25(OH)D and recent RTI symptoms in 6350 middle-aged and elderly participants in the Tromsø Study 6. The main outcome measurement was self-reported RTI symptoms in the previous week.

Tromsø, Norway, 69°N.

Six thousand three hundred and fifty middle-aged and elderly residents of Tromsø.

Of the 6350 included, 791 (12·5 %) reported RTI symptoms in the previous week. We classified serum 25(OH)D concentrations into quartiles and adjusted the data for current smoking habit and month of attendance. The prevalence of RTI symptoms did not increase with decreasing serum 25(OH)D level, was highest in quartile 3 (15·0 %) followed by quartile 4 (12·4 %), and was lowest in quartiles 1 and 2 (11·1 % and 11·4 %). There was no trend for increasing duration of illness with decreasing serum 25(OH)D. The prevalence of RTI symptoms was not significantly associated with the intake of fish, n-3 capsules or vitamin and/or mineral supplements, or sun exposure. Only use of cod-liver oil or fish oil capsules daily or sometimes was significantly associated with fewer RTI symptoms during the preceding 7 d (P = 0·04).

Low serum 25(OH)D was not associated with increased prevalence of recent RTI symptoms. Our findings do not support the idea that vitamin D supplementation can reduce the incidence of RTI in Norway.

The present study aimed to evaluate the frequency of deficiency/insufficiency of vitamin D in adolescents and its relationship to overweight and metabolic disorders.

Cross-sectional study. Nutritional status was assessed by BMI according to WHO recommendations. Dietary intake was evaluated using a 3 d dietary record. The biochemical evaluation comprised measurements of serum lipids, lipoproteins, glucose, insulin, calcidiol (25(OH)D) and parathyroid hormone. Insulin resistance was calculated using the homeostasis model assessment. Body composition and blood pressure were assessed.

Fifteen schools (eight public and seven private) in the central city of Juiz de Fora, Brazil.

The analysis included a study population of 160 adolescents (seventy-seven eutrophic and eighty-three overweight) aged 15 to 17 years.

Vitamin D deficiency and insufficiency was observed in 1·25 and 70·6 % of adolescents, respectively. Serum 25(OH)D levels were statistically lower in adolescents with weight excess, abdominal obesity, hypercholesterolaemia, higher levels of parathyroid hormone, insulin resistance, hyperinsulinaemia and hypertension (P < 0·05). Lower BMI and waist circumference were observed in the third (highest) tertile of vitamin D intake for all adolescents. The high prevalence of vitamin D insufficiency is primarily nutritional and reflects a low vitamin D intake.

Our results support the negative association among serum 25(OH)D levels and vitamin D intake with non-skeletal outcomes in Brazilian adolescents. Vitamin D fortification of foods and/or the use of vitamin D supplements need to be considered to raise vitamin D intake in the adolescent population, even in a sunny country like Brazil.

To investigate whether low vitamin D status was related to insulin resistance (IR) or impaired fasting glucose (IFG) in Korean adolescents, after adjusting for total body fat mass (FM).

A cross-sectional study.

Korea National Health and Nutrition Examination Survey (KNAHNES) 2009–2010.

In total, 1466 participants (769 males) aged 10–19 years were assessed for serum 25-hydroxyvitamin D (25(OH)D) levels, for FM by whole-body dual-energy X-ray absorptiometry and for IR by homeostasis model assessment (HOMA-IR) after an 8 h fast.

Age-, sex-, season- and physical-activity-adjusted regression models showed that serum 25(OH)D levels were significantly related to markers of adiposity (P = 0·016 for FM (g), P = 0·023 for FM (%) and P = 0·035 for fat mass index). When the participants were stratified into three 25(OH)D categories (<37·5 nmol/l (n 553), 37·5 to < 50 nmol/l (n 543) and ≥ 50 nmol/l (n 370)), significantly decreasing trends were observed for fasting insulin (all P < 0·001), HOMA-IR (all P < 0·001) and the odds ratios for IFG (all P for trend < 0·05) from the lowest to the highest 25(OH)D category, after adjustments for age, sex, physical activity and all markers of adiposity. In the multivariate logistic regression analysis, the likelihood of participants in the lowest serum 25(OH)D category having IFG was 2·96–3·15 compared with those in the highest 25(OH)D category (all P < 0·05).

There was a significant inverse relationship between vitamin D status and IR and the risk of IFG, independent of adiposity, in Korean adolescents.

To investigate vitamin D status and its association with components of the metabolic syndrome (MetS) in adolescent girls attending high school in Boukan, Iran during winter 2012.

A cross-sectional study.

High schools of Boukan city, Iran.

A sample of 216 girls aged 14–17 years was selected by multistage random sampling from four districts of Boukan. Weight, height, waist circumference, blood pressure, daily energy intake, physical activity and serum 25-hydroxyvitamin D (25(OH)D), fasting blood glucose, TAG and HDL-cholesterol levels of all participants were evaluated. Serum 25(OH)D level <20 ng/ml was defined as vitamin D deficiency.

Mean serum 25(OH)D was 7·26 (sd 2·81) ng/ml and 96 % of the participants had vitamin D deficiency. According to age-modified definitions of the National Cholesterol Education Program Adult Treatment Panel III, MetS was diagnosed in 10·6 % of the participants. In multivariable regression analysis after adjustment for BMI, energy intake and physical activity level, serum 25(OH)D was inversely associated with fasting blood glucose (β = −0·143, P = 0·04). No significant relationship was found between serum 25(OH)D and other components of MetS.

The high prevalence of vitamin D deficiency warrants national polices and interventions towards improving this major health problem among adolescent girls. Low 25(OH)D level was significantly associated with increased fasting blood glucose. Prospective studies are needed to determine the effects of vitamin D deficiency on the development of MetS and related metabolic diseases in adolescent girls.

To examine the use of vitamin D supplements during infancy among the participants in an international infant feeding trial.

Longitudinal study.

Information about vitamin D supplementation was collected through a validated FFQ at the age of 2 weeks and monthly between the ages of 1 month and 6 months.

Infants (n 2159) with a biological family member affected by type 1 diabetes and with increased human leucocyte antigen-conferred susceptibility to type 1 diabetes from twelve European countries, the USA, Canada and Australia.

Daily use of vitamin D supplements was common during the first 6 months of life in Northern and Central Europe (>80 % of the infants), with somewhat lower rates observed in Southern Europe (>60 %). In Canada, vitamin D supplementation was more common among exclusively breast-fed than other infants (e.g. 71 % v. 44 % at 6 months of age). Less than 2 % of infants in the USA and Australia received any vitamin D supplementation. Higher gestational age, older maternal age and longer maternal education were study-wide associated with greater use of vitamin D supplements.

Most of the infants received vitamin D supplements during the first 6 months of life in the European countries, whereas in Canada only half and in the USA and Australia very few were given supplementation.

To evaluate the prevalence of vitamin D deficiency and insufficiency, as well as their association with Hb and elevated blood lead levels (BLL) in children in China.

A cross-sectional and 1-year retrospective study.

Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, China.

Children aged from 6 months to 14 years living in south-west China who were taken to physical examinations (January–December 2011).

Of 1218 children included in the study, 25-hydroxyvitamin D (25(OH)D) concentration (mean 33·18 (sd 16·48) ng/ml) was deficient in 21·6 % and insufficient in 27·4 %, which were higher than the prevalence of both anaemia at 8·5 % and elevated BLL (Pb ≥ 10 μg/dl) at 1·8 %, but lower than mildly elevated BLL prevalence (5 μg/dl ≤ Pb < 10 μg/dl) at 56·9 %. There was a negative correlation between 25(OH)D concentration and BLL (r = −0·216, P < 0·001) while no significant relationship was found between 25(OH)D concentration and Hb (r = −0·012, P > 0·05). After multivariable adjustment, the significant predictors of 25(OH)D deficiency and insufficiency were increasing child age especially between 8 and 14 years (OR = 18·29; 95 % CI 10·14, 32·99; P < 0·001) and BLL (OR = 1·01; 95 % CI 1·00, 1·02; P = 0·045).

The prevalence of 25(OH)D deficiency and insufficiency was much higher than that of anaemia or elevated BLL in south-west China, and associated with increasing age and BLL.

Open-angle glaucoma (OAG) is one of the major chronic diseases involving the optic nerve. However, little is known about the association between vitamin D and OAG. The present study was conducted to test the hypothesis that lower vitamin D status is associated with greater prevalence of OAG.

Cross-sectional study. Multivariable logistic regression was performed to examine the relationship between serum 25-hydroxyvitamin D (25(OH)D) and OAG after adjusting for traditional potential confounders. OAG was defined by the criteria of the International Society for Geographical and Epidemiological Ophthalmology.

The Fifth Korean National Health and Nutrition Examination Survey conducted in 2010–2011.

Six thousand and ninety-four adult participants randomly selected from 192 surveys in 131 locations in South Korea.

Multivariable-adjusted odds ratios of OAG across quintiles of decreasing 25(OH)D were 1·26, 1·00 (reference), 1·31, 1·36 and 1·69 (P for quadratic trend <0·01). The odds ratio for the lowest 25(OH)D quintile was significantly higher than that for the second quintile (P < 0·01). In addition, we discovered that the predictors for worsening of OAG, such as intraocular pressure or vertical and horizontal cup-to-disc ratios, had a significant relationship with 25(OH)D level.

There was a reverse J-shaped association between 25(OH)D levels and the risk of OAG, with significantly elevated risk at lower 25(OH)D. The findings of this research suggest that vitamin D deficiency should be considered as a potential risk factor for the development of OAG. To our knowledge, the present study is the first one that shows an association between vitamin D status and OAG.

Vitamin D insufficiency is highly prevalent, with particular subgroups at greater risk (e.g. the elderly and those with darker skin). Vitamin D insufficiency may partly explain US racial/ethnic disparities in the prevalence of periodontitis and tooth loss. We evaluated the association between a predictor score of plasma 25-hydroxyvitamin D (25(OH)D) and incidence of periodontitis and tooth loss.

Detailed biennial questionnaires were collected on medical history, lifestyle practices and incident periodontitis and tooth loss. The predictor score was derived from variables known to influence circulating concentrations of plasma 25(OH)D and validated against plasma concentrations among a sub-sample. Multivariable Cox proportional-hazards models with time-varying covariates estimated the association between the predicted 25(OH)D score and time until first tooth loss.

A total of 42 730 participants of the Health Professionals Follow-Up Study aged 40–75 years at baseline were followed from 1986 to 2006.

USA, representing all fifty states and the District of Columbia.

We observed 13 581 incident tooth loss events from 539 335 person-years. There was a dose-dependent significant inverse association across quintiles of the predicted 25(OH)D score and incidence of tooth loss. In multivariable analyses, the highest quintile of the updated predicted 25(OH)D score compared with the lowest was associated with a 20 % lower incidence of tooth loss (hazard ratio = 0·80, 95 % CI 0·76, 0·85; P value for trend <0·0 0 1); UV-B was also independently associated. Results for the predicted 25(OH)D score and periodontitis were similar.

These results are suggestive of an association between predictors of vitamin D and lower incidence of tooth loss and periodontitis.

To measure BMR in a probability sample of adults from an urban city of Brazil and to compare indirectly measured BMR (BMRi) with BMR predicted from different equations.

BMR data were obtained by indirect calorimetry and estimated by different predictive equations (Schofield; Harris and Benedict; Henry and Rees). Anthropometric and body composition measures were also obtained.

The Nutrition, Physical Activity and Health Survey (PNAFS), a household survey conducted in Niterói, Rio de Janeiro state, Brazil.

Representative sample of 529 adults (aged ≥20 years; 339 females) living in Niterói, Rio de Janeiro state, Brazil.

Mean BMRi values were 5839·7 (se 73·9) kJ/d and 4758·1 (se 39·5) kJ/d for men and women, respectively. Predicted BMR by all equations was significantly higher (difference between means and 95 % CI did not include zero) than BMRi in both men and women of all ages. Overall bias in BMR (predicted BMR minus BMRi) using the Schofield equations (overestimation of about 20 %) was higher than when using the Henry and Rees equations (13 % and 16 % overestimation for males and females, respectively). The percentage of individuals whose BMR predicted by the Schofield equations fell within 10 % of BMRi was very low (7·8 % and 14·1 % of males and females, respectively).

Current available predictive equations of BMR are not adequate to estimate BMR in Brazilians living in Niterói, Rio de Janeiro, Brazil.

To evaluate the adequacy and accuracy of cut-off values currently recommended by the WHO for assessment of cardiovascular risk in southern Brazil.

Population-based study aimed at determining the predictive ability of waist circumference for cardiovascular risk based on the use of previous medical diagnosis for hypertension, diabetes mellitus and/or dyslipidaemia. Descriptive analysis was used for the adequacy of current cut-off values of waist circumference, receiver operating characteristic curves were constructed and the most accurate criteria according to the Youden index and points of optimal sensitivity and specificity were identified.

Pelotas, southern Brazil.

Individuals (n 2112) aged ≥20 years living in the city were selected by multistage sampling, since these individuals did not report the presence of previous myocardial infarction, angina pectoris or stroke.

The cut-off values currently recommended by WHO were more appropriate in men than women, with overestimation of cardiovascular risk in women. The area under the receiver operating characteristic curve showed moderate predictive ability of waist circumference in men (0·74, 95 % CI 0·71, 0·76) and women (0·75, 95 % CI 0·73, 0·77). The method of optimal sensitivity and specificity showed better performance in assessing the accuracy, identifying the values of 95 cm in men and 87 cm in women as the best cut-off values of waist circumference to assess cardiovascular risk.

The cut-off values currently recommended for waist circumference are not suitable for women. Longitudinal studies should be conducted to evaluate the consistency of the findings.

To analyse the association between waist-to-height ratio (WtHR) and body fat and to develop predictive adiposity equations that will simplify the diagnosis of obesity in the paediatric age group.

Cross-sectional study conducted in Spain during 2007 and 2008. Anthropometric dimensions were taken according to the International Biology Program. The children were classified as underweight, normal weight, overweight or obese according to national standards of percentage body fat (%BF). WtHR differences among nutritional status categories were evaluated using ANOVA. Correlation analysis and regression analysis were carried out using WtHR as a predictor variable for %BF. A t test was applied to the results obtained by the regression model and by the Siri equation. The degree of agreement between both methods was evaluated by estimating the intra-class correlation coefficient.

Elementary and secondary schools in Madrid (Spain).

Girls (n 1158) and boys (n 1161) from 6 to 14 years old.

WtHR differed significantly (P < 0·001) depending on nutritional status category. This index was correlated (P < 0·001) with all adiposity indicators. The mean %BF values estimated by the regression model (boys: %BF = 106·50 × WtHR – 28·36; girls: %BF = 89·73 × WtHR – 15·40) did not differ from those obtained by the Siri equation. The intra-class correlation coefficient (0·85 in boys, 0·79 in girls) showed a high degree of concordance between both methods.

WtHR proved to be an effective method for predicting relative adiposity in 6–14-year-olds. The developed equations can help to simplify the diagnosis of obesity in schoolchildren.