Within- and Between-Individual Variation in Nutrient Intake in Children and Adolescents

BackgroundLittle is known regarding the number of 24-hour recalls required to rank-order children and adolescents on usual intake for diet–disease studies.ObjectiveTo determine the within- to between-individual variance ratios and number of 24-hour recalls required to rank-order individuals on usual intake for select macro- and micronutrients in a large, multiracial/ethnic sample of children and adolescents.DesignCross-sectional survey.Participants/settingChildren and adolescents ages 6 to 17 years participating in the 2007-2008 and 2009-2010 National Health and Nutrition Examination Survey (NHANES).Main outcome measuresVariance ratios for predefined sex, age (children age 6 to 11 years, adolescents age 12 to 17 years), and racial/ethnic groups (Mexican American/Hispanic, non-Hispanic black, and non-Hispanic white).Statistical analysisMixed-effects linear regression models were used to estimate within- and between-individual variance components for selected nutrients. The number of 24-hour recalls required to rank-order participants on usual intake (absolute values and energy-adjusted) was obtained from the nutrient variance ratios for various levels of accuracy.ResultsVariance ratios were more than 1 for all nutrients examined. High values (variance ratio >3) were observed for protein, saturated and unsaturated fatty acids, cholesterol, and several micronutrients. Variance ratios for absolute nutrient intakes were similar for both sexes within age groups, but higher for children than for adolescents. A total of six to nine and three to six 24-hour recalls were typically sufficient to rank-order children and adolescents, respectively, on usual intake with an accuracy of r=0.8. Additional recalls were required to achieve the same accuracy for energy-adjusted nutrients. Variance ratios were similar for adolescents across racial/ethnic groups, but highly variable in children.ConclusionsA total of six to nine 24-hour recalls may represent a reasonable trade-off between accuracy and participant burden for rank-ordering nutrient intakes in children and adolescents. Additional research is required to determine whether this may be reduced using statistical modeling–based approaches and the number of recalls children and adolescents will reliably complete.     

Trends in Food and Beverage Sources among US Children and Adolescents: 1989-2010

Despite the historical rise and recent plateau of child overweight and obesity, levels remain exceedingly high. To understand these trends and identify targets for intervention it is important to examine concomitant trends in children's diets. The objective of our analysis was to describe 21-year trends in total energy intake and the major food and beverage sources of energy among 2- to 18-year-olds in the United States. Six nationally representative surveys were examined in 2012, the Continuing Survey of Food Intakes by Individuals (1989-1991 and 1994-1996, 1998) and the National Health and Nutrition Examination Survey (2003-2004, 2005-2006, 2007-2008, and 2009-2010). Total energy intake among US children and adolescents rose considerably from 1989 to 2004, and subsequently declined through 2010. Seven sources were consistently major contributors across all time points: sugar-sweetened beverages, pizza, full-fat milk, grain-based desserts, breads, pasta dishes, and savory snacks. Intakes of full-fat milk, meats and processed meat products, ready-to-eat cereals, burgers, fried potatoes, fruit juice, and vegetables decreased from 1989-2010 whereas intakes of nonfat milk, poultry, sweet snacks and candies, and tortilla- and corn-based dishes increased linearly over the 21-year period. Significant nonlinear time trends were observed with recent decreases in intakes of sugar-sweetened beverages, pizza, pasta dishes, breads and rolls, and savory snacks and recent increases in intake of fruit. Energy intakes of US children began to decline in 2003-2004 and continued to decline through 2009-2010. However, among preschool children (aged 2 to 5 years) and children from low-income families, total energy intakes in 2009-2010 still remained significantly higher than in 1989-1991.     

Pulse Intake Improves Nutrient Density among US Adult Consumers

The objective was to examine trends in pulse (dry beans, dry peas, chickpeas and lentils) intake over a 10-year period and to compare nutrient intakes of pulse consumers and non-consumers to better understand the impact of pulse consumption on diet quality in the US population. NHANES 2003–2014 data for respondents (≥19 years) with 2 days of intake was used to evaluate trends in pulse intake. Pulse consumers were identified as those NHANES respondents who consumed pulses on one or both days. Differences in energy adjusted nutrient intakes between non-consumers and consumers were assessed. There were no significant trends in pulse intakes for the total population or for pulse consumers over the 10-year period. In 2013–2014, approximately 27% of adults consumed pulses with an intake of 70.9 ± 2.5 g/day over 2 days, just slightly <0.5 cup equivalents/day. At all levels of consumption, consumers had higher (p < 0.01) energy adjusted intakes of fiber, folate, magnesium. Higher energy adjusted intakes for potassium, zinc, iron and choline and lower intakes of fat were observed for consumers than for non-consumers at intakes ≥69.4 ± 1.01 g/day. These data suggest that pulse consumption in the US population may result in better diet quality with diets that are more nutrient dense than those without pulses.     

Associations between concentrations of uric acid with concentrations of vitamin A and beta-carotene among adults in the United States

Our objective was to examine the cross-sectional associations between concentrations of vitamin A and beta-carotene, a major source of vitamin A, with concentrations of uric acid in a nationally representative sample of adults from the United States. We conducted a cross-sectional study using data from up to 10893 participants aged ≥20 years of National Health and Nutrition Examination Survey from 2001 to 2006. Concentrations of uric acid adjusted for numerous covariates increased from 305.8 μmol/L in the lowest quintile of vitamin A to 335.3 μmol/L in the highest quintile (p for linear trend <0.001). The prevalence ratio for hyperuricemia also increased progressively across quintiles of serum vitamin A reaching 1.82 (95% confidence interval [CI]: 1.52, 2.16; p for linear trend <0.001) in the top quintile in the maximally adjusted model. Adjusted mean concentrations of uric acid decreased progressively from quintile 1 (333.8 μmol/L) through quintile 4 of concentrations of beta-carotene and were similar for quintiles 4 (313.5 μmol/L) and 5 (313.8 μmol/L). Concentrations of beta-carotene were inversely associated with hyperuricemia (adjusted prevalence ratio comparing highest with lowest quintile = 0.61; 95% CI: 0.52, 0.72; p for linear trend <0.001). Concentrations of uric acid were significantly and positively associated with concentrations of vitamin A and inversely with concentrations of beta-carotene. These cross-sectional findings require confirmation with experimental studies of vitamin A and beta-carotene supplementation.     

Increasing Egg Consumption at Breakfast Is Associated with Increased Usual Nutrient Intakes: A Modeling Analysis Using NHANES and the USDA Child and Adult Care Food Program School Breakfast Guidelines

The objective of the current modeling analysis was three-fold: (1) to examine usual nutrient intakes in children when eggs are added into dietary patterns that typically do not contain eggs; (2) to examine usual nutrient intakes with the addition of eggs in the Child and Adult Care Food Program (CACFP) school breakfast; and (3) to examine nutrient adequacy when eggs are included in routine breakfast patterns and with the addition of eggs to the CACFP school breakfast program. Dietary recall data from the National Health and Nutrition Examination Survey 2011–2016 (children aged 1–18 years-old; n = 9254; CACFP n = 159) were used in the analysis. The usual intakes of pantothenic acid, riboflavin, selenium, and vitamin D increased ≥10 percent (relative to the baseline values) with the addition of one egg at breakfast. The usual intakes of protein and vitamin A at breakfast were also increased by more than 10 percent compared to the baseline values with the addition of two eggs. Similar outcomes were observed with the addition of eggs to the CACFP school breakfast. The percent of children above the adequate intake for total choline increased to 43.6 and 57.8% with one and two eggs, respectively, compared to 22.6% at the baseline. The addition of eggs at breakfast can contribute to nutrient intakes and overall dietary adequacy and play a role in public health initiatives aimed at increasing the intake of under-consumed nutrients and nutrients of concern.     

Race/Ethnicity and Income in Relation to the Home Food Environment in US Youth Aged 6 to 19 Years

BackgroundThe home food environment is complex and has the potential to influence dietary habit development in young people. Several factors may influence the home food environment, including income and race/ethnicity.ObjectiveTo examine the relationship of income and race/ethnicity with three home food environment factors (ie, food availability frequency, family meal patterns [frequency of family and home cooked meals], and family food expenditures).DesignA cross-sectional analysis of the National Health and Nutrition Examination Survey (NHANES).ParticipantsA total of 5,096 youth aged 6 to 19 years from a nationally representative sample of US individuals participating in NHANES 2007-10.Statistical analyses performedPrevalence of food availability frequency was assessed for the entire sample, race/ethnicity, poverty income ratio (PIR), and race/ethnicity stratified by PIR. Mean values of family meal patterns and food expenditures were calculated based on race/ethnicity, PIR, and race/ethnicity stratified by PIR using analysis of variance and least squares means. Tests of main effects were used to assess differences in food availability prevalence and mean values of family meal patterns and food expenditures.ResultsNon-Hispanic whites had the highest prevalence of salty snacks (51.1%±1.5%) and fat-free/low-fat milk (39.2%±1.7%) always available. High-income homes had the highest prevalence of fruits (75.4%±2.4%) and fat-free/low-fat milk (38.4%±2.1%) always available. Differences were found for prevalence of food availability when race/ethnicity was stratified by PIR. Non-Hispanic blacks had the lowest prevalence of fat-free/low-fat milk always available across PIR groups. Differences in mean levels of family meal patterns and food expenditures were found for race/ethnicity, PIR, and race/ethnicity stratified by PIR.ConclusionsRace/ethnicity and PIR appear to influence food availability, family meal patterns, and family food expenditures in homes of youth. Knowledge of factors that influence the home food environment could assist in developing effective strategies to improve food environments for young people.     

Leptin Level and Skipping Breakfast: The National Health and Nutrition Examination Survey III (NHANES III)

Skipping breakfast is a common dietary habit considered to be unhealthy. However, the mechanisms underlying skipping breakfast have not been fully explored. Leptin is a hormone that regulates food intake and energy storage and secretes in a diurnal rhythm with lowest levels in the morning. We examined the association between the serum leptin level and skipping breakfast in 5714 adults in the U.S. National Health and Nutrition Examination Survey III, 1988–1994. We defined breakfast as any food or beverage consumed between 5:00 a.m. and 10:00 a.m. using a single 24-h recall. Skipped breakfast was seen in 13.1%. In the logistic regression models with and without adjusting for adiposity and sex, leptin levels were not associated with skipping breakfast. After adjusting for age, race/ethnicity, and time of venipuncture, the association remained insignificant. After further adjusting for potential confounders: physical activity, alcohol intake, smoking and diabetes and after further adjusting for: dietary factors, insulin and glucose levels, there was a 9% and 11%–12%, respectively, statistically significantly higher likelihood of skipping breakfast if the leptin level was more than 50% greater. Further investigation into the biological reasons for skipping breakfast may be useful for promoting healthy lifestyles.     

Distributions and Trends of Serum Lipid Levels among United States Children and Adolescents Ages 4–19 Years: Data from the Third National Health and Nutrition Examination Survey

Background.Atherosclerosis begins in childhood and progresses into adulthood. The reduction of cardiovascular risk factors, such as elevated serum total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels, in childhood may reduce cardiovascular morbidity and mortality in adulthood. Lipid distributions among children and adolescents were examined using the most recent nationally representative data.Methods.Data from 7,499 examinees in NHANES III (1988–1994) were used to estimate mean and percentile distributions of serum total cholesterol, LDL-C, high-density lipoprotein cholesterol (HDL-C), and triglycerides in children and adolescents aged 4 to 19 years. The estimates were analyzed by age, sex, and race/ethnic groups. Trends in mean total cholesterol were examined for 12- to 17-year-olds using data from NHES III (1966–1970), NHANES I (1971–1974), and NHANES III (1988–1994).Results.For children and adolescents 4 to 19 years of age, the 95th percentile for serum total cholesterol was 216 mg/dL and the 75th percentile was 181 mg/dL. Mean age-specific total cholesterol levels peaked at 171 mg/dL at 9–11 years of age and fell thereafter. Females had significantly higher mean total cholesterol and LDL-C levels than did males (P< 0.005). Non-Hispanic black children and adolescents had significantly higher mean total cholesterol, LDL-C, and HDL-C levels compared to non-Hispanic white and Mexican American children and adolescents. The mean total cholesterol level among 12- to 17-year-olds decreased by 7 mg/dL from 1966–1970 to 1988–1994 and is consistent with, but less than, observed trends in adults. Black females have experienced the smallest decline between surveys.Conclusions.The findings provide a picture of the lipid distribution among U.S. children and adolescents and indicate that, like adults, adolescents have experienced a fall in total cholesterol levels. Total cholesterol levels in U.S. adolescents declined from the late 1960s to the early 1990s by an average of 7 mg/dL. This information is useful for planning programs targeting the prevention of cardiovascular disease beginning with the development of heathy lifestyles in childhood.     

Decreased consumption of sugar-sweetened beverages improved selected biomarkers of chronic disease risk among US adults: 1999 to 2010

Consumption of sugar-sweetened beverages (SSBs) increased greatly from the late 1970s to the early part of this decade. Although recent data show that consumption of SSB may now be declining, consumption levels still remain much higher than recommended. Using data from the National Health and Nutrition Examination Survey, we assessed trends in intakes of SSB and levels of chronic disease biomarkers from 1999 to 2010 and examined the associations of SSB intake and biomarkers of chronic disease risk. We hypothesized that SSB intake will decrease and biomarkers of chronic disease risk will improve, therefore indicating that high intake of SSB is associated with greater chronic disease risk. Univariate analysis showed that from 1999 to 2010, SSB consumption decreased (P for trend = .0026), high-density lipoprotein increased (P for trend < .0001), low-density lipoprotein decreased (P for trend = .0007), and C-reactive protein decreased (P for trend = .0096). Using multivariate analysis, we showed that higher intakes of SSB were associated with lower high-density lipoprotein (P for trend < .0001), in an unadjusted model and all models with increasing numbers of covariates, and higher C-reactive protein (P for trend < .05), in an unadjusted model and in models with age, race/ethnicity, sex, education level, and poverty income ratio adjustments. We conclude that SSB consumption is associated with biomarkers of chronic disease risk, independent of demographic and lifestyle factors.     

Iron Deficiency Is Associated with Food Insecurity in Pregnant Females in the United States: National Health and Nutrition Examination Survey 1999-2010

Food-insecure pregnant females may be at greater risk of iron deficiency (ID) because nutrition needs increase and more resources are needed to secure food during pregnancy. This may result in a higher risk of infant low birth weight and possibly cognitive impairment in the neonate. The relationships of food insecurity and poverty income ratio (PIR) with iron intake and ID among pregnant females in the United States were investigated using National Health and Nutrition Examination Survey 1999-2010 data (n=1,045). Food security status was classified using the US Food Security Survey Module. One 24-hour dietary recall and a 30-day supplement recall were used to assess iron intake. Ferritin, soluble transferrin receptor, or total body iron classified ID. Difference of supplement intake prevalence, difference in mean iron intake, and association of ID and food security status or PIR were assessed using χ² analysis, Student t test, and logistic regression analysis (adjusted for age, race, survey year, PIR/food security status, education, parity, trimester, smoking, C-reactive protein level, and health insurance coverage), respectively. Mean dietary iron intake was similar among groups. Mean supplemental and total iron intake were lower, whereas odds of ID, classified by ferritin status, were 2.90 times higher for food-insecure pregnant females compared with food-secure pregnant females. Other indicators of ID were not associated with food security status. PIR was not associated with iron intake or ID. Food insecurity status may be a better indicator compared with income status to identify populations at whom to direct interventions aimed at improving access and education regarding iron-rich foods and supplements.     

Association between household income and overweight of Korean and American children: trends and differences

The prevalence of overweight in children has been dramatically increasing worldwide, and socioeconomic status is an important risk factor. The purpose of this study was to examine the hypothesis that household income is negatively associated with overweight in Korean and American girls and boys. In the study, 2117 children 7 to 12 years of age from the Korean National Health and Nutrition Examination Survey between 2001 and 2007 and 3016 children from the US National Health and Nutrition Examination Survey between 2001 and 2006 were included. Overweight is defined as the sex- and age-specific body mass index cutoffs recommended by the International Obesity Task Force. Lower household income significantly increased the risk for overweight in Korean boys, irrespective of adjustments. The negative association between household income and overweight of American boys disappeared after adjusting for the frequency of dining out and TV viewing time. There was no significant association between household income and overweight of Korean and American girls. As household income increased, the intake of energy from protein was increased, but energy from carbohydrates was decreased in Korean boys. On the other hand, as household income increased, energy intake from carbohydrates was increased and energy intake from proteins decreased in American boys. In conclusion, positive association between household income and overweight was found in Korean boys, but not in Korean girls and American boys and girls. Effects solely targeting reduction in income disparities cannot effectively reduce sex disparities in overweight of children.     

Association between Serum Triglycerides and Prostate Specific Antigen (PSA) among U.S. Males: National Health and Nutrition Examination Survey (NHANES), 2003–2010

(1) Background: Increasing evidence indicates that lipid metabolism may influence the concentration of prostate-specific antigen (PSA). However, the association between triglycerides and PSA remains unclear and complicated. Hence, we evaluated the correlation between triglycerides and PSA based on the U.S. National Health and Nutrition Examination Survey (NHANES) database. (2) Methods: A total of 2910 participants out of 41,156 participants fit into our study after conducting the screening from the 2003 to 2010 NHANES survey. Serum triglycerides were the independent variable of our study, and PSA was the dependent variable; (3) Results: In our study, the average age of chosen participants was 59.7 years (±12.7). After adjusting for covariates, the result indicated that for each additional unit of serum triglyceride (mg/dL), the PSA concentrations were reduced by 0.0043 ng/mL (−0.0082, −0.0005) with a statistical difference. Furthermore, we used machine learning of the XGBoost model to determine the relative importance of selected variables as well as constructed a smooth curve based on the fully adjusted model to investigate the possible linear relationship between the triglyceride and PSA concentrations. (4) Conclusions: The serum triglyceride is independently and negatively correlated with PSA among American males, which may make it hard to detect asymptomatic prostate cancer and diagnose at an advance stage with higher triglycerides due to detection bias.     

Analysis of the Effects of Nutrient Intake and Dietary Habits on Depression in Korean Adults

While several studies have explored nutrient intake and dietary habits associated with depression, few studies have reflected recent trends and demographic factors. Therefore, we examined how nutrient intake and eating habits are associated with depression, according to gender and age. We performed simple and multiple regressions using nationally representative samples of 10,106 subjects from the Korea National Health and Nutrition Examination Survey. The results indicated that cholesterol, dietary fiber, sodium, frequency of breakfast, lunch, dinner, and eating out were significantly associated with depression (p-value < 0.05). Moreover, depression was associated with nutrient intake and dietary habits by gender and age group: sugar, breakfast, lunch, and eating out frequency in the young women’s group; sodium and lunch frequency among middle-age men; dietary fibers, breakfast, and eating out frequency among middle-age women; energy, moisture, carbohydrate, lunch, and dinner frequency in late middle-age men; breakfast and lunch frequency among late middle-age women; vitamin A, carotene, lunch, and eating out frequency among older age men; and fat, saturated fatty acids, omega-3 fatty acid, omega-6 fatty acid, and eating out frequency among the older age women’s group (p-value < 0.05). This study can be used to establish dietary strategies for depression prevention, considering gender and age.     

Food Sources of Total Energy and Nutrients among U.S. Infants and Toddlers: National Health and Nutrition Examination Survey 2005–2012

Understanding the dietary intakes of infants and toddlers is important because early life nutrition influences future health outcomes. The aim of this study was to determine the dietary sources of total energy and 16 nutrients in a nationally representative sample of U.S. infants and toddlers aged 0–24 months. Data from the 2005–2012 National Health and Nutrition Examination Survey were analyzed. Dietary intake was assessed in 2740 subjects using one 24-h dietary recall. The population proportion was used to determine the contribution of foods and beverages to nutrient intakes. Overall infant formulas and baby foods were the leading sources of total energy and nutrients in infants aged 0–11.9 months. In toddlers, the diversity of food groups contributing to nutrient intakes was much greater. Important sources of total energy included milk, 100% juice and grain based mixed dishes. A number of foods of low nutritional quality also contributed to energy intakes including sweet bakery products, sugar-sweetened beverages and savory snacks. Overall non-flavored milks and ready-to-eat cereals were the most important contributors to micronutrient intakes. In conclusion this information can be used to guide parents regarding appropriate food selection as well as inform targeted dietary strategies within public health initiatives to improve the diets of infants and toddlers.     

Consumption of Ultra-Processed Foods Increases the Likelihood of Having Obesity in Korean Women

This study aimed to determine the association between consumption of ultra-processed foods and obesity among Korean adults. We used the data of 7364 participants (men 3219, women 4145) aged 19–64 years from the Korea National Health and Nutrition Examination Survey (KNHANES), 2016–2018. Food items were classified using the NOVA food classification system, depending on the extent and purpose of food processing: (1) unprocessed or minimally processed foods, (2) processed culinary ingredients, (3) processed foods, and (4) ultra-processed foods. Consumption of ultra-processed foods accounted for 26.8% of the total energy intake. After adjusting for potential confounders including sociodemographic and lifestyle characteristics, subjects with the highest consumption of ultra-processed foods (fourth quartile of % energy intake from ultra-processed foods) had 0.61 kg/m² higher body mass index (BMI; 95% confidence interval [CI] 0.23–0.99, p-trend 0.0047), 1.34 cm higher waist circumference (WC; 95% CI 0.35–2.34, p-trend 0.0146), 51% higher odds of being obese (BMI > 25 kg/m²; odds ratio [OR] 1.51, 95% CI 1.14–1.99, p-trend 0.0037), and 64% higher odds of abdominal obesity (men: WC ≥ 90 cm, women: WC ≥ 85 cm; OR 1.64, 95% CI 1.24–2.16, p-trend 0.0004) than those with the lowest consumption (first quartile) among women. However, no association was found in men. These findings provide evidence that high consumption of ultra-processed foods is positively associated with obesity in Korean women. Further studies with a large-scale cohort or intervention trial are needed to identify the mechanism of associations between consumption of ultra-processed foods and health-related outcomes including obesity in Korea.     

Environmental lead and childhood blood lead levels in US children: NHANES, 1999–2006

Although blood lead levels in the United States have fallen dramatically since 1980, there remain subgroups of children with high blood lead levels. We assessed the relationship between environmental lead sources and blood lead levels in children ages 1 to 5 years from the National Health and Nutrition Examination Survey (NHANES), 1999–2006. Modeled ambient air lead levels and industrial lead releases at the census-tract level were assigned to each child's residence with adjustment for confounding factors. Of 3,223 children, 272 (8.4%) had blood lead levels ≥ 5 ug/dL. Industrial releases (2,252 vs 1,696 lbs/mi²) and ambient air lead levels (2.28 vs 1.75 ng/m³) were greater in exposed versus unexposed children. For every 10,000 lb/mi² increase in inverse distance squared weighted exposure, there was a 1.13% increase (95% CI: 0.45%, 1.81%) in blood lead (p = .001).     

Did School Meal Programs and SNAP Participation Improve Diet Quality of US Children from Low-Income Households: Evidence from NHANES 2013–2014?

Nutrition assistance programs such as school meals and the Supplemental Nutrition Assistance Program (SNAP) are designed to provide a safety net for the dietary intake of children from low-income families. However, compared with eligible non-participants, the relationship of diet quality with school meals only and school meals + SNAP is not well understood. The objectives of the study include: (1) To explore whether and to what extent nutrition assistance program participation (school meals only and school meals + SNAP) is related to diet quality; and (2) to examine the differences of diet quality between participating in school meals only, school meals + SNAP, or non-participation among American children. Children aged 5 to 18 years old from income eligible households who participated in the 2013–2014 National Health and Nutrition Examination Survey (NHANES) were included in this cross-sectional study (n = 1425). Diet quality was measured using the Healthy Eating Index (HEI)–2015 and its 13 subcomponents. A Rao-Scott Chi-square test, propensity scores approach, and Analysis of Covariance were performed. Covariates included age, sex, race/ethnicity, weight status, and family monthly poverty index. SAS survey procedures were used to incorporate the appropriate sample design weights. Participation in school meals + SNAP was not associated with higher diet quality compared to eligible non-participants or school meals-only participants. Participation in school meals + SNAP improved the intake of total dairy, but not added sugars or total vegetables compared to school meals only. Overall, school meal + SNAP participation did not significantly improve the overall diet quality of children in low-income households relative to comparable non-participants.     

Serum Selenium Concentrations and Diabetes in U.S. Adults: National Health and Nutrition Examination Survey (NHANES) 2003–2004

Background

Increasing evidence suggests that high selenium levels are associated with diabetes and other cardiometabolic risk factors.

Objectives

We evaluated the association of serum selenium concentrations with fasting plasma glucose, glycosylated hemoglobin levels, and diabetes in the most recently available representative sample of the U.S. population.

Methods

We used a cross-sectional analysis of 917 adults ≥ 40 years of age who had a fasting morning blood sample in the National Health and Nutrition Examination Survey 2003–2004. We evaluated the association of serum selenium, measured by inductively coupled plasma-dynamic reaction cell-mass spectrometry, and diabetes, defined as a self-report of current use of hypoglycemic agents or insulin or as fasting plasma glucose ≥ 126 mg/dL.

Results

Mean serum selenium was 137.1 μg/L. The multivariable adjusted odds ratio [95% confidence interval (CI)] for diabetes comparing the highest quartile of serum selenium (≥ 147 μg/L) with the lowest (< 124 μg/L) was 7.64 (3.34–17.46). The corresponding average differences (95% CI) in fasting plasma glucose and glycosylated hemoglobin were 9.5 mg/dL (3.4–15.6 mg/dL) and 0.30% (0.14–0.46%), respectively. In spline regression models, the prevalence of diabetes as well as glucose and glycosylated hemoglobin levels increased with increasing selenium concentrations up to 160 μg/L.

Conclusions

In U.S. adults, high serum selenium concentrations were associated with higher prevalence of diabetes and higher fasting plasma glucose and glycosylated hemoglobin levels. Given high selenium intake in the U.S. population, further research is needed to determine the role of excess selenium levels in the development or the progression of diabetes.     

Early-Adulthood Weight Change and Later Physical Activity in Relation to Cardiovascular and All-Cause Mortality: NHANES 1999–2014

Limited evidence investigated the combined influence of early-adulthood weight change and later physical activity on the risk of cardiovascular (CVD) and all-cause mortality. The aim of this study is to explore the associations of early-adulthood weight change and later physical activity with CVD and all-cause mortality. This is a cohort study of 23,193 US adults aged 40 to 85 years from the National Health and Nutrition Examination Survey (NHANES) 1999 to 2014. Cox proportional hazards regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) of CVD and all-cause mortality associated with early-adulthood weight change and later physical activity. During a median follow-up of 9.2 years, there were 533 and 2734 cases of CVD and all-cause deaths. Compared with being physically inactive, the HRs of the CVD mortality of being physically active were 0.44 (0.26 to 0.73), 0.58 (0.19 to 1.82), 0.38 (0.17 to 0.86) and 0.46 (0.21 to 1.02) among individuals with stable normal, stable obese, non-obese to obese and maximum overweight early-adulthood weight change patterns. Using stable normal patterns that were physically active later as the reference, other early-adulthood weight change patterns did not show a significantly higher risk of CVD mortality when participants were physically active in later life; later physically inactive participants had a significantly increased risk of CVD mortality, with HRs of 2.17 (1.30 to 3.63), 5.32 (2.51 to 11.28), 2.59 (1.29 to 5.18) and 2.63 (1.32 to 5.26) in the stable normal, stable obese, non-obese to obese and maximum overweight groups, respectively. Similar results can be seen in the analyses for all-cause mortality. Our findings suggest that inadequate physical activity worsens the negative impact of unhealthy early-adulthood weight change patterns, which is worthy of being noted in the improvement of public health.     

Prevalence and correlates of vitamin D deficiency in US adults

Mounting evidence suggests that vitamin D deficiency could be linked to several chronic diseases, including cardiovascular disease and cancer. The purpose of this study was to examine the prevalence of vitamin D deficiency and its correlates to test the hypothesis that vitamin D deficiency was common in the US population, especially in certain minority groups. The National Health and Nutrition Examination Survey 2005 to 2006 data were analyzed for vitamin D levels in adult participants (N = 4495). Vitamin D deficiency was defined as a serum 25-hydroxyvitamin D concentrations ≤20 ng/mL (50 nmol/L). The overall prevalence rate of vitamin D deficiency was 41.6%, with the highest rate seen in blacks (82.1%), followed by Hispanics (69.2%). Vitamin D deficiency was significantly more common among those who had no college education, were obese, with a poor health status, hypertension, low high-density lipoprotein cholesterol level, or not consuming milk daily (all P < .001). Multivariate analyses showed that being from a non-white race, not college educated, obese, having low high-density lipoprotein cholesterol, poor health, and no daily milk consumption were all significantly, independently associated with vitamin D deficiency (all P < .05). In summary, vitamin D deficiency was common in the US population, especially among blacks and Hispanics. Given that vitamin D deficiency is linked to some of the important risk factors of leading causes of death in the United States, it is important that health professionals are aware of this connection and offer dietary and other intervention strategies to correct vitamin D deficiency, especially in minority groups.