Dylan M. Williams

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BACKGROUND Increasing evidence suggests a role for mineral metabolism in cardiovascular disease risk. 25-hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH), and calcium may be directly associated with cardiovascular risk factors or mediated by each other. METHODOLOGY/PRINCIPAL FINDINGS We combined data for adult participants in three cycles of the(More)
OBJECTIVE Lower maternal vitamin D status in pregnancy may be associated with increased offspring cardiovascular risk in later life, but evidence for this is scant. We examined associations of maternal total 25-hydroxyvitamin D (25(OH)D) in pregnancy with offspring cardiovascular risk factors assessed in childhood and adolescence. DESIGN A longitudinal,(More)
OBJECTIVE To examine independent associations of serum 25-hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH) and calcium with a range of cardiovascular risk factors in adolescents. DESIGN Cross-sectional population-based study. SETTING A nationally representative sample of the US adolescent population. PARTICIPANTS Healthy adolescents (aged 12-19)(More)
BACKGROUND High serum calcium levels have been associated with cognitive decline in older adults. These associations have not been studied in younger adults. The possible association of vitamin D with cognitive function, independent of calcium, is unknown. METHODS A cross-sectional study of associations of serum ionized calcium and 25-hydroxyvitamin D(More)
CONTEXT Studies in adults have reported associations of low circulating total 25-hydroxyvitamin D with increased cardiovascular disease and risk factors. Evidence of associations in children, however, is limited, and it is unknown whether associations with risk factors differ for each 25-hydroxyvitamin D analog [25-hydroxyvitamin D(2) (25[OH]D(2)) and(More)
Studies in middle- and older-aged adults have shown positive associations between serum levels of 25-hydroxyvitamin D [25(OH)D] and cognitive function. Higher serum calcium levels have been associated with greater cognitive decline in older adults. There have been relatively few studies of the associations of 25(OH)D and calcium with cognitive function in(More)
Haptoglobin binds free haemoglobin that prevents oxidative damage produced by haemolysis. There is a copy number variant (CNV) in the haptoglobin gene (HP) consisting of two alleles, Hp1 (no duplication), and Hp2 (1.7kb duplication involving two exons). The spread of the Hp2 allele is believed to have taken place under selective pressures conferred by(More)
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(More)
BACKGROUND Studies of the associations of circulating total 25-hydroxyvitamin D (25(OH)D) with cardiovascular disease risk factors in adults have reported inconsistent findings. We aimed to compare prospective associations of two analogues of childhood 25(OH)D (25(OH)D2 and 25(OH)D3) with cardiovascular risk factors measured in adolescence. METHODS AND(More)
Higher vitamin D status, lower adiposity, and longer telomere length are each reportedly associated with lower risk of several chronic diseases and all-cause mortality. However, direct relationships between vitamin D status (measured by circulating 25-hydroxyvitamin D (25(OH)D) concentration), adiposity, and telomere length are not well established. We(More)