Margaret A. McDowell

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PURPOSE To describe physical activity levels of children (6-11 yr), adolescents (12-19 yr), and adults (20+ yr), using objective data obtained with accelerometers from a representative sample of the U.S. population. METHODS These results were obtained from the 2003-2004 National Health and Nutritional Examination Survey (NHANES), a cross-sectional study(More)
CONTEXT The prevalence of overweight in children and adolescents and obesity in adults in the United States has increased over several decades. OBJECTIVE To provide current estimates of the prevalence and trends of overweight in children and adolescents and obesity in adults. DESIGN, SETTING, AND PARTICIPANTS Analysis of height and weight measurements(More)
Exposure to methyl mercury, a risk factor for neurodevelopmental toxicity, was assessed in U.S. children 1-5 years of age (n = 838) and women 16-49 years of age (n = 1,726) using hair mercury analysis during the 1999-2000 National Health and Nutrition Examination Survey (NHANES). The data are nationally representative and are based on analysis of(More)
This report presents national anthropometric reference data based on health examination survey results from the National Health and Nutrition Examination Survey (NHANES), 1999-2002, for all ages of the U.S. population. Weighted population means, standard errors of the means, and selected percentiles are presented for the total U.S. population by sex, race(More)
Over 34% of adults aged 20 years and older are obese, but there has been no significant change in the prevalence since 2003-2004. The increasing trend in obesity over the last 25 years is a result of a shift in the entire BMI distribution and an increase in the prevalence of those who are extremely obese. In addition, disparities continue to exist.(More)
CONTEXT Humans are exposed to methylmercury, a well-established neurotoxin, through fish consumption. The fetus is most sensitive to the adverse effects of exposure. The extent of exposure to methylmercury in US women of reproductive age is not known. OBJECTIVE To describe the distribution of blood mercury levels in US children and women of childbearing(More)
Assessment of diet is a critical component of the third National Health and Nutrition Examination Survey (NHANES III), which was designed to describe the health and nutritional status of the US population. We analyzed data collected with the primary dietary assessment instrument used in NHANES III, the 24-h recall, for 7769 nonpregnant adults aged > or = 20(More)
KEY FINDINGS Use of dietary supplements is common among the U.S. adult population. Over 40% used supplements in 1988-1994, and over one-half in 2003-2006. Multivitamins/multiminerals are the most commonly used dietary supplements, with approximately 40% of men and women reporting use during 2003-2006. Use of supplemental calcium increased from 28% during(More)
OBJECTIVE This report presents national anthropometric reference data for the U.S. population aged 3 months and older in 1988-1994. METHODS Data in this report are from the Third National Health and Nutrition Examination Survey (NHANES III), which was conducted on a complex, stratified, multistage probability sample of the civilian, noninstitutionalized(More)
BACKGROUND Mercury amalgam dental restorations have been used by dentists since the mid 19th century and issues on safety continue to be periodically debated within the scientific and public health communities. Previous studies have reported a positive association between urine mercury levels and the number of dental amalgams, but this relation has never(More)