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BACKGROUND/OBJECTIVES: Iron is fundamental to many basic biological functions, and animal studies suggest that iron deficiency early in life can have a lasting impact on the developing brain. SUBJECTS/METHODS: We used a population-based cohort of mothers and their children to assess the effect of iron status among pregnant women on the cognitive ability of their offspring. But to avoid the inherent confounding that occurs within observational epidemiology studies we examined the association of maternal genotype at single-nucleotide polymorphisms in the genes HFE (rs1799945) and (rs1800562), TF (rs3811647) and TMPRSS6 (rs1800562), which are related to iron, haemoglobin or transferrin levels, on their child's cognitive test scores at age 8. RESULTS: We found strong associations between HFE and TMPRSS6 genotypes and mother's haemoglobin levels early in pregnancy (P-values are all ≤ 4.1 x [10.sup.- 5]) and a genetic score comprised of alleles at these loci was even more strongly associated with haemoglobin levels (P = 3.0 x [10.sup.-18]), suggesting that this was a good instrument to use to look at the effect of prenatal iron levels on offspring cognition. However, mother's genotype at the above loci was not associated with offspring IQ at age 8. CONCLUSIONS: We therefore concluded that there is no evidence of an effect of exposure to low levels of iron (within the normal range) in pregnancy on offspring cognition at age 8. However, pregnant women in the UK with low haemoglobin levels are prescribed iron supplements and so we were unable to look at the effect of iron deficiency in our study. European Journal of Clinical Nutrition (2014) 68, 496-502; doi:10.1038/ejcn.2013.265; published online 8 January 2014 Keywords: iron; IQ; intelligence; genetic variants; mendelian randomization; ALSPAC 12.6 1.1 29 -0.174 12.3 0.9 717 12.4 1.0 1721 -0.103 0.032 4.6 x [10.sup.-8] 0.34 0.016 3.6 x [10.sup.-10] 0.55 17 (65.4) 5 (19.2) 283 (42.0) 218 (32.3) 759 (47.4) 481 (30.1) 4 (15.4) 0.04 173 (25.7) 360 (22.5) 0.01 8 (28.6) 9 (32.1) 184 (27.1) 226 (33.3) 506 (30.9) 567 (34.6) 11 (39.3) 1.00 (0.88, 1.14) 269 (39.6) 566 (34.5) 1.03 (0.97, 1.10) 0.99 (0.85, 1.15) 1.03 (0.95, 1.11) 107.1 12.8 15 103.6 17.3 390 104.3 16.0 962 -0.52 (-2.05, 1.00) -0.74 (-1.52, 0.05) 0.38 (-1.57, 2.32) -0.23 (-1.23, 0.77), INTRODUCTION Iron is fundamental to many basic biological functions including oxygen transport, production of adenosine triphosphate (ATP), DNA synthesis, mitochondrial function and protection of cells from oxidative damage. (1) However, [...]

Background: Evidence suggests that higher levels of vitamin D and calcium are associated with greater lung function and that vitamin D is inversely associated with atopic sensitisation. It is unknown whether the associations of vitamin D and calcium with lung function are independent of each other or mediated by atopic sensitisation. Objective: To study the associations of 25-hydroxyvitamin D (25(OH)D) and ionised calcium levels with lung function and specific allergen sensitisation in adolescents (12-19 years) and adults (20-59 years) and to assess whether the associations with lung function are due to altered atopic sensitisation. Methods: This is a cross-sectional analysis of the data from the third National Health and Nutrition Examination Survey. Results: The 25(OH)D levels were positively associated with forced vital capacity in adolescents (0.035 (95% confidence interval (CI): 0.007-0.064) s.d.;s.d. in model adjusted for multiple confounders). This association and the previously reported association between higher serum levels of 25(OH)D and better lung function in adults were independent of serum calcium levels, which were not associated with lung function. In adults, calcium was associated with sensitisation to grass allergens (odds ratio pers.d., 1.17 (95% CI: 1.03-1.32), 1.15 (95% CI: 1.01-1.31) and 1.18 (95% CI: 1.06-1.32) for white oak, Bermuda grass and short ragweed, respectively) and peanut odds ratio 1.21 (95% CI: 1.02-1.43) after adjusting for age, gender and race/ethnicity, but these associations attenuated towards the null after adjusting for additional confounders. The associations were independent of 25(OH)D levels, which were not associated with allergen sensitisation. Conclusions: Circulating levels of 25(OH)D are positively associated with lung function and this does not seem to be driven by allergen sensitisation or influenced by calcium levels. doi:10.1038/ejcn.2011.6; published online 16 February 2011 Keywords: vitamin D; calcium; allergy; spirometry; the third National Health and Nutrition Examination Survey, Introduction Atopy is characterised by a tendency to mount immunoglobulin E-mediated, type I hypersensitivity reactions to allergens. It is strongly associated with allergic diseases, including asthma. In many Western countries, [...]

Objective: To compare childhood obesity prevalence in England and the United States using different criteria. Subjects/Methods: Participants included 2- to 17-year olds in the Health Survey for England (HSE, n = 33 563) and the US National Health and Nutrition Examination Survey (NHANES, n = 14 540) 1999 through 2006. Mean body mass index (BMI) and prevalence of obesity were compared using the UK 1990, US 2000 Centers for Disease Control and International Obesity Task Force (IOTF) criteria. Results: English children at ages 2-5 years had a higher mean BMI than US children (mean difference (English minus US) = 0.41 kg/[m.sup.2], 95% confidence intervals (CI) 0.31-0.52). At age ≥8 years, mean BMI was lower in England (for ages 8-11 years, mean difference = -1.00 kg/[m.sup.2], 95% CI -1.26 to -0.75; for ages 12-17 years, mean difference = -1.37 kg/[m.sup.2], 95% CI -1.59 to -1.14). The IOTF criteria produced the lowest estimates of obesity prevalence. The 2000 Centre for Disease Control and Prevention (CDC) criteria produced the highest estimates in younger children and the UK 1990 criteria produced the highest in adolescents. Children aged 2-5 years in England had higher prevalence of obesity than those in the United States when using the 2000 CDC and UK 1990 criteria. US adolescents had the highest prevalence of obesity by age group using each of the three criteria. Conclusion: The 2000 CDC and UK 1990 criteria give a higher prevalence of obesity in England than in the United States at ages 2-5 years; however, at age X8 years, the reverse is true. Estimates of childhood obesity prevalence rely on the criteria used, which has implications for surveillance and clinical practice. European Journal of Clinical Nutrition (2011) 65, 143-150; doi: 10.1038/ejcn.2010.260; published online 15 December 2010 Keywords: adolescent; body weight; child; epidemiologic measurements; obesity; overweight, Introduction Since 1970, the greatest increases in obesity in school children have been in North America and Western Europe (Wang and Lobstein, 2006). International comparisons are important for documenting and [...]

Objective: To explore whether searching specialised bibliographic databases identified additional relevant papers to those located by a Medline search for a systematic review of exercise therapy. Method: Searches were performed in Medline, two further generalised medical databases (Embase, Cochrane Library) and four specialised databases (CancerLit, Cinahl, PsychInfo, SportDiscus) to identify controlled trials of exercise interventions for cancer patients. Results: A total of 749 different publications were Located through the search, of which 18 met inclusion criteria. Fifteen (83%) of these were identified through Medline and three (17%) from three individual specialised databases. A further seven studies meeting inclusion criteria were located through reference lists and contact with experts. Conclusion: In this example, searching Medline and additional specialised databases along with checking reference lists and contacting experts was the most effective means of ensuring that all relevant papers were included in the review. Searching Medline alone for systematic reviews of exercise or other unconventional therapies is likely to be inadequate.