The effect of body mass index on adequacy of serum 25-hydroxyvitamin D levels in US adults: the National Health and Nutrition Examination Survey 2001 to 2006

PurposeTo investigate the relationship between body mass index (BMI) and vitamin D adequacy among US adults.MethodsWe used data for US adults aged 18 years or older (n = 12,927) who participated in the 2001 to 2006 United States National Health and Nutrition Examination Survey. Log-binomial regression was used to estimate the strength of association between BMI categories and the prevalence of serum 25-hydroxyvitamin D [25(OH)D] greater than or equal to 20 ng/mL before and after controlling for selected characteristics. An interaction term between race or ethnicity and BMI categories was tested.ResultsAmong US adults, 67.2% had serum 25(OH)D greater than or equal to 20 ng/mL, a cut point suggested by the Office of Dietary Supplements for adequate bone and general health. Overweight and obese adults were 8% (95% confidence interval, 0.89–0.95) and 26% (95% confidence interval, 0.71–0.78), respectively, less likely to have serum 25(OH)D greater than or equal to 20 ng/mL than their normal weight counterparts after controlling for age, gender, race/ethnicity, nativity and marital status, as well as education and income. No heterogeneity of the association between BMI categories and the prevalence of 25(OH)D greater than or equal to 20 ng/mL was observed by race or ethnicity.ConclusionsThe low prevalence of 25(OH)D greater than equal to 20 ng/mL among overweight and obese adults in the US population underscores the need to comparatively assess vitamin D intakes across different BMIs.     

Acculturation in the United States is associated with lower serum carotenoid levels: Third National Health and Nutrition Examination Survey

This study examined the association of acculturation in the United States and serum carotenoid levels. The design was a cross-sectional, nationally representative survey of 16,539 participants, 17 years of age and older, from the Third National Health and Nutrition Examination Survey (NHANES III). The main outcome measures were serum levels of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, lycopene, and total carotenoids. Multivariate linear regression was used to model the association of serum carotenoids and country of birth, language of interview, and years in the United States. Adjustments were made for age, sex, years of education, race/ethnicity, body mass index, alcohol use, physical activity, serum cotinine, serum cholesterol, and vitamin/mineral usage. Individuals born in the United States who speak English had the lowest levels of carotenoids, and individuals born in Mexico had the highest levels of carotenoids, with the exception of lycopene. Years of residence in the United States was associated with lower alpha-carotene (4.18 vs 1.51), beta-carotene (20.21 vs 14.87), beta-cryptoxanthin (12.51 vs 8.95), lutein/zeaxanthin (25.15 vs 18.03), and total carotenoids (88.79 vs 75.44). Years residence in the United States was positively associated with higher lycopene levels (26.69 vs 32.03). Acculturation in the United States was associated with lower fruit and vegetable intake, as measured by serum carotenoid levels.     

Risk factors for low serum 25-hydroxyvitamin D concentrations in otherwise healthy children and adolescents

BACKGROUND: Serum 25-hydroxyvitamin D [25(OH)D] concentrations serve as a biomarker for vitamin D stores. Prior studies have not examined the risk factors for low vitamin D concentrations in a multiethnic sample of US youth across a broad age range. OBJECTIVE: The objective was to determine the prevalence of and factors associated with low concentrations of 25(OH)D in children and adolescents. DESIGN: Serum 25(OH)D concentrations were measured in 382 healthy children aged 6-21 y living in the northeastern United States. Dietary and supplemental vitamin D intake was assessed by interview. Fat and lean mass were assessed by dual-energy X-ray absorptiometry. Multivariable ordinal logistic regression was used to determine factors associated with decreased concentrations of 25(OH)D. RESULTS: The median concentration of 25(OH)D was 28 ng/mL (interquartile range: 19-35 ng/mL), and 55% of subjects had 25(OH)D concentrations <30 ng/mL. 25(OH)D concentrations were inversely correlated with parathyroid hormone concentrations (Spearman's r=-0.31, P<0.001) but were not significantly correlated with 1,25-dihydroxyvitamin D concentrations. In the multivariable model, older age (P<0.001), black race [odds ratio (OR): 14.2; 95% CI: 8.53, 23.5], wintertime study visit (OR: 3.55; 95% CI: 2.29, 5.50), and total daily vitamin D intake <200 IU (OR: 1.58; 95% CI: 1.02, 2.46) were associated with low vitamin D concentrations. Fat and lean mass were not independently associated with vitamin D status in this healthy-weight sample. CONCLUSION: Low serum 25(OH)D concentrations are prevalent in otherwise healthy children and adolescents in the northeastern United States and are related to low vitamin D intake, race, and season.     

Components of 25-hydroxyvitamin D in serum of young children in upper midwestern United States.

The relative importance of cholecalciferof (vitamin D3) and ergocalciferol (vitamin D2) in maintaining the vitamin D level in children (1/2 to 6 years old) living in the upper midwestern United States was determined by measurement of total 25-hydroxyvitamin D (25-OH-D), its components, and other indices of calcium homeostasis in serum. In 38 normal children, mean (range) serum total 25-OH-D was 32.8 (less than 5 to 53) ng/ml; in 25 of the 28 sera partitioned, the major component was 25-OH-D3. Significant seasonal variation in serum 25-OH-D3 (mean, range: 35.2, 17 to 51 ng/ml in summer and 15.9, less than 5 to 32 ng/ml in winter) was not accompanied by changes in mean serum 25-OH-D2, calcium, phosphorus, or alkaline phosphatase values. However, individual serum total 25-OH-D values correlated with serum phosphorus values (r = 0.37; P less than 0.05). The proportion of the total represented by 25-OH-D3 varied widely, with a a mean of 83% in summer and 67% in winter. Sources of D3, which include both dermal synthesis and intestinal absorption of D3 added to milk, appear to be more important than sources of D2 in maintaining vitamin D nutrition of young children throughout the year. However, sources of D2 offset the decrease in total 25-OH-D in winter months.     

Human papillomavirus vaccine coverage in the United States, National Health and Nutrition Examination Survey, 2007-2008

Objectives

This study aims to estimate human papillomavirus (HPV) vaccine coverage by demographic and sexual behavior characteristics 1-2 years after vaccine licensure in a nationally representative sample of females aged 9-59 years in the United States.

Methods

In 2007-2008, a total of 2775 females aged 9-59 years responded to questions on HPV vaccine receipt in the National Health and Nutrition Examination Survey (NHANES). Demographic and sexual characteristics were evaluated for select age categories in bivariate analyses after adjusting for survey design.

Results

Overall, 15.2% of females aged 11-26 years reported HPV vaccine initiation; vaccine initiation varied significantly by age. We found no significant difference in vaccine initiation by race or poverty level in either 11-18 or 19-26-year olds. Significantly more 19-26-year olds with private insurance initiated vaccine (16.3%) than those with public insurance (4.0%) (p = 0.04). Among females aged 14-18 years, vaccine initiation was higher in those who ever had sex (28.6%) compared to those who had never had sex (17.8%) (p = 0.05).

Conclusions

These results describe HPV vaccine initiation shortly after vaccine licensure. Vaccine initiation was highest in females aged 14-18 years. Efforts should be made to increase HPV vaccine coverage for the recommended age groups.     

Asthma and maternal body mass index are related to pediatric body mass index and obesity: results from the Third National Health and Nutrition Examination Survey

OBJECTIVE: Clinical research has shown an increased prevalence of obesity in children with asthma. This study was designed to assess the relationship between asthma and pediatric body mass index (BMI) in a national database and to examine factors that may modify this relationship. DESIGN: The cross-sectional relationship between asthma and pediatric BMI and obesity (BMI > or = 85th percentile) was studied. Variables that may influence the relationship between asthma and pediatric BMI, such as race/ethnicity and television watching were included in the model for the total sample. A smaller sample of 3,009 white and African American youth were studied in regression models including maternal BMI. STUDY POPULATION: A nationally representative cross-sectional sample of 5154 children and adolescents of 6 to 16 years of age from the Third National Health And Nutrition Examination Survey. RESULTS: In the full sample, asthma and television watching were related to BMI, accounting for 3% of the variance in BMI. When maternal BMI was included in the non-Hispanic sample, television watching, maternal BMI, and the interaction of maternal BMI and asthma were related to youth BMI, accounting for 15% of the variance. The standardized BMI z-score for those youth without asthma and no maternal obesity was 0.06, which increased to 0.33 if the youth had asthma, to 0.70 if the youth did not have asthma but the mother was obese, and to 1.71 if the youth had asthma and the mother was obese. Asthma, television watching, and maternal BMI were independent predictors of youth obesity. CONCLUSIONS: BMI and prevalence of obesity is higher in youth with asthma. Pediatric BMI, but not obesity, is also related to the interaction of asthma and maternal BMI in white and African American youth. Comorbidity of asthma and obesity may complicate treatment of either condition, and prevention of obesity should be encouraged for asthmatic children.     

Serum 25-hydroxyvitamin D concentrations in girls aged 4-8 y living in the southeastern United States

BACKGROUND: Evidence suggests that adults and adolescents throughout the United States are at risk of poor vitamin D status. However, vitamin D concentrations in young American children have not been assessed. OBJECTIVE: The relations between serum 25-hydroxyvitamin D [25(OH)D] and bone were examined in prepubertal girls. DESIGN: In the present cross-sectional study, serum 25(OH)D concentration was assessed in 168 prepubertal girls aged 4-8 y living in the southeastern United States with the use of radioimmunoassay. Bone area, bone mineral content, and areal bone mineral density were measured from total body, lumbar spine, proximal femur, and forearm with dual-energy X-ray absorptiometry. Data were analyzed with analysis of variance, analysis of covariance, stepwise multiple regression, and partial correlations. RESULTS: The mean (+/-SD) serum 25(OH)D was 93.8 +/- 28.1 nmol/L (range: 31.1-181.4 nmol/L). In a multiple regression analysis, race and season were the strongest predictors of vitamin D status. The black girls had lower mean 25(OH)D values than did the white girls (P < 0.01), and 25(OH)D values were significantly different in the total sample between the seasons (P < 0.001), ranging from 74.4 nmol/L during the winter months to 107 nmol/L during the summer. After adjustment for season, age, race, and body mass index, 25(OH)D values were negatively correlated with forearm bone mineral content (r = -0.18; P = 0.02). CONCLUSIONS: Unlike prior reports of adults and adolescents living in the southeastern United States, vitamin D status was adequate in the children of the present study. 25(OH)D concentrations were not positively associated with higher bone mineral.     

Population determinants of serum lycopene concentrations in the United States: data from the Third National Health and Nutrition Examination Survey, 1988-1994

Serum lycopene is inversely related to the risk for cancer and cardiovascular diseases. We used data from the Third National Health and Nutrition Examination Survey, 1988-1994, to investigate the relation between serum lycopene concentrations and sex, age, geographical location, race-ethnicity, education, alcohol, smoking, BMI, blood pressure, serum total cholesterol and triacylglycerol, and intakes of fat, tomatoes and tomato-based products in 3413 individuals aged 17-90 y. Multivariate adjusted mean lycopene concentrations were 48.3% lower in individuals > or =70 y old than in those 17 to <30 y old (P < 0.0001), 7.6% lower in women than in men (P = 0.0045), 15.1% lower in people living in the South than those in the West (P < 0.0001), 10.3 and 61.0% lower in the 1st quartile than in the 4th quartile for dietary fat intake (P = 0.0173) and serum cholesterol (P < 0.0001), respectively, 11.1% lower in tomato noneaters than those who ate tomatoes > or =31 times/mo (P = 0.0085), 13.5% lower in pizza noneaters than those who ate pizza > or =16 times/mo (P = 0.0016), and 20.6% lower in pasta noneaters than those who ate pasta (with tomato sauce) > or =16 times/mo (P < 0.0001). Race-ethnicity, alcohol, BMI, blood pressure, and consumption of non-tomato vegetables, and fruits and juices had no association with serum lycopene concentrations. Sex, age, geographical region, socioeconomic status, serum total cholesterol, smoking, and intakes of fat, tomatoes, pizza, and pasta were significant determinants of serum lycopene concentrations in the United States.     

Factors associated with low water intake among South Korean adolescents - Korea National Health and Nutrition Examination Survey, 2007-2010

Water is essential for life and plain water instead of sugar-sweetened beverages is one approach for decreasing energy intake. Due to limited data on characteristics associated with water intake among Korean adolescents, this study examined associations of demographic and behavioral characteristics with plain water intake by using nationally representative sample of South Korean adolescents. The data (2007-2010 Korea National Health and Nutrition Examination Survey) for 1,288 high school-aged adolescents (15-18 years) were used. Multivariable logistic regression was used to calculate adjusted odds ratios (OR) for factors associated with low water intake (< 4 cups/day) and very low water intake (< 2.5 cups/day). Nationwide, 38.4% and 19.0% of adolescents reported drinking water < 4.0 cups/day and < 2.5 cups/day, respectively. The mean plain water intake was 5.7 cups/day for males and 4.1 cups/day for females. Females had significantly higher odds for drinking water < 2.5 cups/day (OR = 2.2) than males, whereas adolescents with low milk consumption had significantly lower odds for drinking water < 2.5 cups/day (OR = 0.7). Factors significantly associated with a greater odds for drinking water < 4 cups/daywere being female (OR = 2.8) and not meeting physical activity recommendations (≥ 20 min/day on < 3 days/week) (OR = 1.6). Being underweight, overweight, and obese were significantly associated with reduced odds for drinking water < 4 cups/day (OR = 0.7, 0.4 and 0.5, respectively). However, intake of soda, coffee drinks, fruits, vegetables, and sodium and eating out were not significantly associated with low or very low water intake. These findings may be used to target intervention efforts to increase plain water intake as part of a healty lifestyle.     

Frequency of leisure-time physical activity and serum 25-hydroxyvitamin D levels in the US population: results from the Third National Health and Nutrition Examination Survey

The decline in vitamin D status among older people is probably due to decreased synthesis of vitamin D by sun-exposed skin and/or decreased outdoor activity. The authors examined the association between outdoor leisure physical activity and serum 25-hydroxyvitamin D in the Third National Health and Nutrition Examination Survey (1988-1994) (n = 15,148 aged >/=20 years). The mean 25-hydroxyvitamin D concentration declined with increasing age, with 79, 73, and 68 nmol/liter for persons aged 20-39, 40-59, and 60 or more years. The proportion that engaged in outdoor activity in the past month was 80% for persons aged 20-39 and 40-59 years but 71% for those aged 60 or more years. In contrast, the mean difference in 25-hydroxyvitamin D between those who participated in outdoor activities daily compared with those who did not participate in the past month was similar for the youngest and oldest age groups: 13 and 16 nmol/liter, respectively. Those persons aged 60 or more years who participated in daily outdoor activities had a mean 25-hydroxyvitamin D concentration similar to that of persons aged 20-39 years: 77 versus 79 nmol/liter, respectively. These nationally representative data suggest that persons aged 60 or more years can synthesize enough vitamin D from daily outdoor activities to maintain vitamin D levels similar to those of young adults.     

Season and ethnicity are determinants of serum 25-hydroxyvitamin D concentrations in New Zealand children aged 5-14 y

New Zealand children, particularly those of Māori and Pacific ethnicity, may be at risk for low vitamin D status because of low vitamin D intakes, the country's latitude (35-46 degrees S), and skin color. The aim of this study was to determine 25-hydroxyvitamin D concentrations and their determinants in a national sample of New Zealand children aged 5-14 y. The 2002 National Children's Nutrition Survey was designed to survey New Zealand children, including oversampling of Māori and Pacific children to allow ethnic-specific analyses. A 2-stage recruitment process occurred using a random selection of schools, and children within each school. Serum 25-hydroxyvitamin D concentration [mean (99% CI) nmol/L] in Māori children (n = 456) was 43 (38,49), in Pacific (n = 646) 36 (31,42), and in New Zealand European and Others (NZEO) (n = 483) 53 (47,59). Among Māori, Pacific, and NZEO, the prevalence (%, 99% CI) of serum 25-hydroxyvitamin D deficiency (<17.5 nmol/L) was 5 (2,12), 8 (5,14), and 3 (1,7), respectively. The prevalence of insufficiency (<37.5 nmol/L) was 41 (29,53), 59 (42,75), and 25 (15,35), respectively. Multiple regression analysis found that 25-hydroxyvitamin D concentrations were lower in winter than summer [adjusted mean difference (99% CI) nmol/L; 15 (8,22)], lower in girls than boys [5 (1,10)], and lower in obese children than in those of "normal" weight [6 (1,11)]. Relative to NZEO, 25-hydroxyvitamin D concentrations were lower in Māori [9 (3,15)] and Pacific children [16 (10,22)]. Ethnicity and season are major determinants of serum 25-hydroxyvitamin D. There is a high prevalence of vitamin D insufficiency in New Zealand children, which may or may not contribute to increased risk of osteoporosis and other chronic disease. There is a pressing need for more convincing evidence concerning the health risks associated with the low vitamin D status in New Zealand children.     

Growth abnormalities in Mexican-American children in the United States: The National Health and Nutrition Examination Survey I Study

Numerous regional studies have indicated a high prevalence of growth abnormalities among Mexican-American children. It has been suggested that this is a constitutional problem. In order to evaluate this, a comparison of selected parameters of growth and nutritional status were made between Mexican-American and European-American children (<19 years) using the National Health and Nutrition Examination Survey I. Height, weight, body mass index (BMI) and daily dietary energy intake were standardized for age and sex, and compared using analysis of variance techniques. Socioeconomic status was analyzed by utilizing a poverty index. Our results show that 10 percent of MA children fall below the 5th percentile for height while weight is normally distributed. On analysis by SES, low SES MA children were dramatically stunted and exhibited marked elevations in BMI in comparison to low SES EA children. These differences diminished with increasing SES so that at high SES, no differences in height or BMI were noted. While no differences in weight within SES categories were demonstrated between MA and EA children, there was a distinct trend toward increasing weight with increasing SES. MA children demonstrated a difference in caloric intake as compared to EA children only at low SES. The observation that abnormalities in growth seen in MA children at low SES levels disappear at higher SES levels suggests that growth abnormalities among MA children are due to environmental as opposed to genetic factors.     

Homocysteine and blood pressure in the Third National Health and Nutrition Examination Survey, 1988-1994

Studies suggest that homocysteine may elevate blood pressure and increase the risk of hypertension. The association of homocysteine with blood pressure and with the risk of hypertension was investigated using cross-sectional data from the Third National Health and Nutrition Examination Survey (1998-1994). Homocysteine had an independent positive association with blood pressure after adjusting for cardiovascular risk factors. A 1 standard deviation ( approximately 5 micro mol/liter) increase in homocysteine was associated with increases in diastolic and systolic blood pressure of 0.5 and 0.7 mmHg, respectively, in men and of 0.7 and 1.2 mmHg in women. Similarly, higher levels of homocysteine were associated with an increased risk of hypertension. In a comparison of the highest and lowest quintiles of homocysteine, women had a threefold increase in the risk of hypertension (95% confidence interval (CI): 1.7, 5.4), and men had a twofold increase (95% CI: 0.7, 5.1). In light of the homocysteine-blood pressure association, the association of homocysteine with prevalent cardiovascular disease was examined with and without adjusting for blood pressure. The results support a mediating role for blood pressure in women and suggest that the full effect of homocysteine on cardiovascular risk may be underestimated when blood pressure is adjusted.     

Healthy Eating Index scores are associated with blood nutrient concentrations in the third National Health And Nutrition Examination Survey

OBJECTIVES: The Healthy Eating Index (HEI) is a summary measure of dietary quality, based on a 100-point scale. Our objectives were to assess the HEI as a measure of dietary status through its correlation with nutritional biomarkers and to identify those biomarkers most associated with diet quality and healthful food intake patterns. DESIGN: National Health and Nutrition Examination Survey (NHANES) III, 1988-94. SUBJECTS: Adults (> or =17 years) with calculated HEI scores and blood nutrient data (n=16,467). STATISTICAL ANALYSES PERFORMED: Weighted crude and partial Pearson correlation coefficients (r) between HEI scores and blood nutrients were calculated. Geometric mean blood nutrient concentrations were calculated for five HEI score categories (ranging from < or =50 to >80). RESULTS: HEI score was positively correlated with serum (r=0.25) and red blood cell (r=0.27) folate, serum vitamins C (r=0.30) and E (r=0.21), and all serum carotenoids except lycopene (r=0.17 to 0.27). These blood nutrient concentrations were 21% to 175% higher for participants in the highest HEI score group (>80) compared with those in the lowest group (< or =50). Mean HEI scores were significantly (P<.0001) greater among the 42% of participants who took dietary supplements. Most correlations were attenuated when adjusted for additional factors. CONCLUSIONS: HEI score is correlated with a wide range of blood nutrients; the strongest relationships are with biomarkers of fruit and vegetable intake. These results are an important step in the validation of the HEI, emphasizing its potential as a tool for nutrition and health studies.     

Drinking patterns and body mass index in never smokers: National Health Interview Survey, 1997-2001

Alcohol could contribute to obesity. The authors examined the relation between drinking patterns and body mass index (BMI) (weight (kg)/height (m)(2)) by pooling cross-sectional data from the 1997-2001 National Health Interview Surveys. Weighted analyses included 45,896 adult never smokers who were current alcohol drinkers. Height and weight were self-reported. In adjusted analyses, alcohol quantity and frequency had opposite associations with BMI. As quantity increased from 1 drink/drinking day to > or =4 drinks/drinking day, BMI significantly increased; in men, it increased from 26.5 (95% confidence interval (CI): 26.3, 26.6) to 27.5 (95% CI: 27.4, 27.7), and in women, it increased from 25.1 (95% CI: 25.0, 25.2) to 25.9 (95% CI: 25.5, 26.3). As frequency increased from low quintiles of drinking days/year to high quintiles, BMI significantly decreased; in men, it decreased from 27.4 (95% CI: 27.2, 27.6) to 26.3 (95% CI: 26.2, 26.5), and in women, it decreased from 26.2 (95% CI: 26.0, 26.5) to 24.3 (95% CI: 24.2, 24.5). In stratified analyses of frequency trends within quantity categories, BMI declines were more pronounced in women than in men, but all linear trends were inverse and significant (p trend < 0.001). In all respondents combined, persons who consumed the smallest quantity the most frequently were leanest, and those who consumed the greatest quantity the least frequently were heaviest. Alcohol may contribute to excess body weight among certain drinkers.     

Optimal vitamin D status attenuates the age-associated increase in systolic blood pressure in white Americans: results from the third National Health and Nutrition Examination Survey

BACKGROUND: The prevalences of both hypertension and vitamin D insufficiency are high in the United States. Recent clinical trials and animal studies have suggested that vitamin D insufficiency may be associated with elevated blood pressure. OBJECTIVE: With cross-sectional data, we sought to determine whether vitamin D concentrations were related to systolic blood pressure (SBP) in the third National Health and Nutrition Examination Survey (1988-1992). DESIGN: Blood pressure was classified with 5 categories from the Joint National Committee 7 with a sixth category added to distinguish participants with normotensive SBP (<110 mm Hg) from those with high-normal SBP (110-119 mm Hg). We used predicted marginals to estimate the conditional means of serum 25 hydroxyvitamin D [25(OH)D] and to test for trend across blood pressure categories. We used linear regression to explore the association between vitamin D, blood pressure, and age. RESULTS: Lower 25(OH)D concentrations were associated with a higher blood pressure category in whites (P<0.001); however, when controlling for age, the association was no longer significant. Concentrations of 25(OH)D>80 nmol/L decreased the age-related increase in SBP by 20% compared with participants having 25(OH)D concentrations<50 nmol/L (P<0.001). Only 8% of blacks had 25(OH)D concentrations>80 nmol/L. CONCLUSIONS: SBP is inversely associated with serum vitamin D concentrations in nonhypertensive white persons in the United States. This observation provides a rationale for studies on the potential effects of vitamin D supplementation as a method to reduce SBP in persons at risk of hypertension.     

Added Sugar Intake among Pregnant Women in the United States: National Health and Nutrition Examination Survey 2003-2012

Background

Despite associations of dietary added sugar with excess weight gain and chronic disease risk, intake among most Americans exceeds the recommended limits (<10% total energy). Maternal diet plays an important role in pregnancy-related outcomes, but little is known about the extent of added sugar intake during pregnancy.