Micronutrient intakes of pre-adolescent children living in London

Salt intake and blood pressure in Iranian children and adolescents: a population-based study

BACKGROUND

Previous studies have reported a high prevalence of hypertension in Iranian students, especially in rural areas. The aim of this study was to investigate the daily intake of salt in students and its association with high blood pressure.

METHODS

A random sub-sample was selected from the participants of the second phase of Shahroud schoolchildren eye cohort study and then a random urine sample was tested for sodium, potassium and creatinine. Urine electrolyte esexcretion and daily salt intake were calculated by Tanaka et al.'s formula.

RESULTS

Among 1455 participants (including 230 participants from rural area and 472 girls), the mean age was 12.9 ± 1.7 year and the mean daily salt intake was 9.7 ± 2.6 g (95% CI 9.5-9.8). The mean salt consumption in rural areas [10.8 (95% CI 10.4-11.2)] was higher than urban areas [9.4 (95% CI 9.3-9.6)], in people with hypertension [10.8 (95% CI 10.3-11.3)] was more than people with normal blood pressure [9.4 (95% CI 9.3-9.6)], and in boys [9.8 (95% CI 9.7-10.0)] was more than girls [9.3 (95% CI 9.1-9.6)]. Higher age, BMI z-score, male sex and rural life, were associated with increased daily salt intake. Increased salt intake was associated with increased systolic and diastolic blood pressure.

CONCLUSION

Daily salt intake in Iranian adolescents was about 2 times the recommended amount of the World Health Organization, was higher in rural areas and was associated with blood pressure. Reducing salt intake should be considered as an important intervention, especially in rural areas.

Zinc Supplementation Increases Procollagen Type 1 Amino-Terminal Propeptide in Premenarcheal Girls: A Randomized Controlled Trial

BACKGROUND

Data have shown that healthy children and adolescents have an inadequate intake of zinc, an essential nutrient for growth. It is unclear whether zinc supplementation can enhance bone health during this rapid period of growth and development.

OBJECTIVE

The primary aim of this study was to determine the effect of zinc supplementation on biochemical markers of bone turnover and growth in girls entering the early stages of puberty. The secondary aim was to test moderation by race, body mass index (BMI) classification, and plasma zinc status at baseline.

METHODS

One hundred forty seven girls aged 9-11 y (46% black) were randomly assigned to a daily oral zinc tablet (9 mg elemental zinc; n = 75) or an identical placebo (n = 72) for 4 wk. Fasting plasma zinc, procollagen type 1 amino-terminal propeptide (P1NP; a bone formation marker), carboxy-terminal telopeptide region of type 1 collagen (ICTP; a bone resorption marker), and insulin-like growth factor I (IGF-I) were assessed at baseline and post-test. Additional markers of bone formation (osteocalcin) and resorption (urinary pyridinoline and deoxypyridinoline) were also measured.

RESULTS

Four weeks of zinc supplementation increased plasma zinc concentrations compared with placebo [mean change, 1.8 μmol/L (95% CI: 1.0, 2.6) compared with 0.2 μmol/L (95% CI: -0.3, 0.7); P < 0.01]. Zinc supplementation also increased serum P1NP concentrations compared with placebo [mean change, 23.8 μmol/L (95% CI: -14.9, 62.5) compared with -31.0 μmol/L (95% CI: -66.4, 4.2); P = 0.04). There was no effect from zinc supplementation on osteocalcin, ICTP, pyridinoline, deoxypyridinoline, or IGF-I. There was no moderation by race, BMI classification, or plasma zinc status at baseline.

CONCLUSIONS

Our data suggest that 4 wk of zinc supplementation increases bone formation in premenarcheal girls. Further studies are needed to determine whether supplemental zinc can improve childhood bone strength. This trial was registered at clinicaltrials.gov as NCT01892098.

High sodium and low potassium intake among Italian children: relationship with age, body mass and blood pressure

Background

Hypertension is the leading cause of death in developed countries and reduction of salt intake is recommended as a key preventive measure.

Objective

To assess the dietary sodium and potassium intakes in a national sample of Italian children and adolescents and to examine their relationships with BMI and blood pressure (BP) in the framework of the MINISAL survey, a program supported by the Italian Ministry of Health.

Population and Methods

The study population included 1424 healthy subjects (766 boys, 658 girls) aged 6-18 years (mean age: 10.1±2.9) who were consecutively recruited in participating National Health Service centers in 10 Italian regions. Electrolyte intake was estimated from 24 hour urine collections tested for completeness by the concomitant measurement of creatinine content. Anthropometric indices and BP were measured with standardized procedures.

Results

The average estimated sodium intake was 129 mmol (7.4 g of salt) per day among boys and 117 mmol (6.7 g of salt) among girls. Ninety-three percent of the boys and 89% of the girls had a consumption higher than the recommended age-specific standard dietary target. The estimated average daily potassium intakes were 39 mmol (1.53 g) and 36 mmol (1.40 g), respectively, over 96% of the boys and 98% of the girls having a potassium intake lower than the recommended adequate intake. The mean sodium/potassium ratio was similar among boys and girls (3.5 and 3.4, respectively) and over 3-fold greater than the desirable level. Sodium intake was directly related to age, body mass and BP in the whole population.

Conclusions

The Italian pediatric population is characterized by excessive sodium and deficient potassium intake. These data suggest that future campaigns should focus on children and adolescents as a major target in the framework of a population strategy of cardiovascular prevention.

Relationship of total 25-OH vitamin D concentrations to Indices of Multiple Deprivation: geoanalysis of laboratory results

Background

Vitamin D deficiency appears to be widespread and associated with ethnicity and economic status. Geography is the key to virtually all national statistics. It provides a structure for collecting, processing, storing and aggregating data. Linking geographic data to laboratory data allows analysis of the association of laboratory data with economic indicators.

Methods

The laboratory information system was searched to create a data-set of total 25-OH vitamin D concentrations, which was then linked to economic (Indices of Multiple Deprivation [IMD]) and ethnicity data using postcodes geocoded to Lower Super Output Areas (LSOAs).

Results

A total of 12422 25-OH vitamin D requests were received during the time period searched. A total of 12167 of these had associated postcodes that would allow georeferencing to LSOAs. The median total 25-OH vitamin D was 24.5 nmol/L (5.3-99.0; 2.5-97.5th percentile). Statistically significant (Spearman rank) correlations were found between median 25-OH vitamin D (nmol/L) and percentage of non-White population and percentage of non-White population and IMD. No statistically significant correlation between median 25-OH vitamin D concentration and IMD was found; however, a statistically significant correlation between percentage of population classified as severely deficient and IMD was found.

Conclusions

In summary, vitamin D deficiency is widespread and is related to ethnicity; it does not appear to be related to economic status except in cases of severe vitamin D deficiency.

Dietary patterns and breast-feeding in Australian children

OBJECTIVE

To determine the dietary patterns of a national sample of 2-8-year-old Australian children and to establish whether breast-feeding is associated with dietary patterns in this age group.

DESIGN

Cross-sectional study using 24 h recall data from the 2007 Australian National Children's Nutrition and Physical Activity Survey.

SETTING

Australia.

SUBJECTS

A total of 2287 children aged 2-8 years.

RESULTS

Principal component factor analysis identified three distinct patterns. The 'Non-core food groups' pattern included food groups such as whole-fat dairy products, cheese, medium-high sugar-sweetened breakfast cereals and sweet biscuits, no fruit, reduced/low-fat dairy products and wholegrain bread/rolls. The 'Healthy, meat and vegetable' pattern included vegetables, red meat, fruit and wholegrain bread/rolls and was inversely associated with take-away foods and carbonated sugar-sweetened beverages. The 'Combination' pattern contained many food groups including candy (not chocolate based), pasta/rice products, nuts/seeds, cakes and chocolate, but no fruit or vegetables. Of the 2287 children, 2064 (89·3 %) had been breast-fed. A positive association was found between breast-feeding and the healthy, meat and vegetable pattern (r = 0·267) but not with the other two patterns. Higher scores on this pattern were also associated with younger age, lower BMI, higher birth weight, high likelihood of being in the less-disadvantaged Socio-economic Indexes for Areas category and less likelihood of the child's parents having a lower educational level.

CONCLUSIONS

These results provide suggestive evidence that breast-feeding during infancy is associated with a healthy dietary pattern in childhood and offers a likely pathway to explain the previously reported association between breast-feeding and chronic disease.