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B M Popkin

Publications and source records attributed to B M Popkin.

At least 55 records · Page 3Linked to original sources
PubMed2000

Determinants of adolescent physical activity and inactivity patterns.

OBJECTIVES: Despite recognition of the important influence of environmental determinants on physical activity patterns, minimal empirical research has been done to assess the impact of environmental/contextual determinants of physical activity. This article aims to investigate environmental and sociodemographic determinants of physical activity and inactivity patterns among subpopulations of US adolescents. We define environmental determinants as modifiable factors in the physical environment that impose a direct influence on the opportunity to engage in physical activity. The present research examines environmental and sociodemographic determinants of physical activity and inactivity with the implication that these findings can point toward societal-level intervention strategies for increasing physical activity and decreasing inactivity among adolescents. STUDY DESIGN AND METHODOLOGY: The study population consists of nationally representative data from the 1996 National Longitudinal Study of Adolescent Health on 17 766 US adolescents enrolled in US middle and high schools (including 3933 non-Hispanic blacks, 3148 Hispanics, and 1337 Asians). Hours/week of inactivity (TV/video viewing and video/computer games) and times/week of moderate to vigorous physical activity were collected by questionnaire. Outcome variables were moderate to vigorous physical activity and inactivity, which were broken into categories (physical activity: 0-2 times/week, 3-4 times/week, and >/=5 times/week; inactivity: 0-10 hours/week, 11-24 hours/week, and >/=25 hours/week). Sociodemographic and environmental correlates of physical activity and inactivity were used as exposure and control variables and included sex, age, urban residence, participation in school physical education program, use of community recreation center, total reported incidents of serious crime in neighborhood, socioeconomic status, ethnicity, generation of residence in the United States, presence of mother/father in household, pregnancy status, work status, in-school status, region, and month of interview. Logistic regression models of high versus low and medium physical activity and inactivity were used to investigate sex and ethnic interactions in relation to environmental and sociodemographic factors to examine evidence for the potential impact of physical education and recreation programs and sociodemographic factors on physical activity and inactivity patterns. RESULTS: Moderate to vigorous physical activity was lower and inactivity higher for non-Hispanic black and Hispanic adolescents. Participation in school physical education programs was considerably low for these adolescents and decreased with age. Participation in daily school physical education (PE) program classes (adjusted odds ratio [AOR]: 2.21; confidence interval [CI]: 1.82-2.68) and use of a community recreation center (AOR: 1.75; CI: 1.56-1.96) were associated with an increased likelihood of engaging in high level moderate to vigorous physical activity. Maternal education was inversely associated with high inactivity patterns; for example, having a mother with a graduate or professional degree was associated with an AOR of.61 (CI:.48-.76) for high inactivity. High family income was associated with increased moderate to vigorous physical activity (AOR: 1.43; CI: 1.22-1.67) and decreased inactivity (AOR:.70; CI:.59-.82). High neighborhood serious crime level was associated with a decreased likelihood of falling in the highest category of moderate to vigorous physical activity (AOR:.77; CI:.66-.91). CONCLUSIONS: These results show important associations between modifiable environmental factors, such as participation in school PE and community recreation programs, with activity patterns of adolescents. Despite the marked and significant impact of participation in school PE programs on physical activity patterns of US adolescents, few adolescents participated in such school PE programs; only 21.3% of all adolescents

Adolescent↗
PubMed1999

Dietary patterns and trends in the United States: the UNC-CH approach.

Over the past 2 decades our group of nutrition and economics researchers at the University of North Carolina at Chapel Hill has used a wide array of methods to study eating patterns and dietary trends. Our focus has been on characterising the way diet has changed over time and identifying some of the major factors underlying these trends. The complexity of this undertaking has led us to develop a number of unique systems for classifying foods and assessing the overall quality of diet. We have also addressed the challenges that exist when measuring changes in both the food supply and food-related behaviors over time. This paper summarises some of the methodological work related to food grouping, overall diet quality indices, and trends research as well as the challenges we still face in this arena.

Diet↗
PubMed1999

The Diet Quality Index revised: a measurement instrument for populations.

OBJECTIVE: To evaluate a revision of the Diet Quality Index called the Diet Quality Index Revised (DQI-R). DESIGN: The original Diet Quality Index was revised to reflect current dietary guidance, to incorporate improved methods of estimating food servings, and to develop and incorporate measures of dietary variety and moderation. The scoring of the original scale was reversed in direction and expanded to a 100-point scale to improve interpretability. METHODS/SUBJECTS: Data from the 1994 Continuing Survey of Food Intakes by Individuals were used. A sample of 3,202 adults aged 18 and older contributed 2 days of dietary intake data based on 24-hour recalls for the development and revision of various components of the DQI-R. STATISTICAL ANALYSES: Pearson correlation analyses, ordinary least squares regression analyses, and a nonparametric test to determine trends across ordered groups were used. RESULTS: The mean DQI-R score for the 1994 sample was 63.4 of a possible 100-point score. Sample respondents were more likely to have met dietary guidance in the areas of dietary cholesterol (66.9% met goal) and iron intakes (59.6% met goal) relative to the Recommended Dietary Allowances but less likely to have met goals related to fruit servings (19.6% met goal), grain servings (23.1% met goal), and calcium intakes (16.6% met goal) relative to the Recommended Dietary Allowance. There is a statistically significant quantitative and qualitative improvement in all components of the DQI-R as one moves from the lowest grouping of scores to the highest. For example, persons with DQI-R scores less than 40 consumed 43.9% of energy from fat, 72% of the Adequate Intake for calcium, and 6.7% of the recommended servings of fruit per day. In contrast, those with DQI-R scores greater than 80 consumed 24.2% of energy from fat, 101% of the Adequate Intake for calcium, and 137% of the recommended servings of fruit per day. APPLICATIONS: The DQI-R reflects the dietary guidance principles of macronutrient distribution, moderation, variety, and proportionality. Although the index was designed to monitor dietary changes in populations rather than individuals, each index component reflects an aspect of national dietary guidance. Calculation of DQI-R scores for an individual should provide an estimate of diet quality relative to national guidelines, and differences in scores over time should suggest improvement or decline in overall diet quality.

Adolescent↗
PubMed1999

Adolescent physical activity and inactivity vary by ethnicity: The National Longitudinal Study of Adolescent Health.

OBJECTIVES: To determine the extent to which physical activity and inactivity patterns vary by ethnicity among subpopulations of US adolescents. STUDY DESIGN: Nationally representative data from the 1996 National Longitudinal Study of Adolescent Health of >14,000 US adolescents (including 3135 non-Hispanic blacks, 2446 Hispanics, and 976 Asians). METHODS: Hours per week of inactivity (TV viewing, playing video or computer games) and times per week of moderate to vigorous physical activity were collected by using questionnaire data. Multinomial logistic regression models of physical activity and inactivity were used to adjust for sociodemographic factors. RESULTS: Large ethnic differences are seen for inactivity, particularly for hours of television or video viewing per week (non-Hispanic blacks, mean = 20.4; non-Hispanic whites, mean = 13.1). Physical activity (>/=5 bouts of moderate to vigorous physical activity per week, 5-8 metabolic equivalents) is lowest for female and minority adolescents. Ethnic differences are far greater for inactivity than for moderate to vigorous physical activity. CONCLUSION: Minority adolescents, with the exception of Asian females, have consistently higher levels of inactivity. Results vary by sex; males have higher inactivity and physical activity, whereas lowest physical activity is found for non-Hispanic black and Asian females, although Asian females also have low inactivity and low levels of overweight. Overall, efforts to reduce the problem of adolescent overweight should focus on increasing activity levels of adolescents, particularly female, older, and major minority subpopulations.

Adolescent↗
PubMed1999

Sex difference in measures of body fatness and the possible difference in the effect of dietary fat on body fatness in men and women.

OBJECTIVES: To examine the sex difference in anthropometric measures of body fatness and to explore the possibility that diet may have differential effects on body fatness in men and women. DESIGN: Prospective study design. SETTING: The first and second China Health and Nutrition Survey conducted in 1989 and 1991, respectively. SUBJECTS: 1449 men and 1683 women age 20-35 y at the baseline (1989) survey. METHODS: Anthropometric measures of body fatness in men and women were compared. Statistical methods were used to explore the potential difference in the effect of dietary fat on body fatness in men and women. RESULTS: Measures of body fatness, especially peripheral fatness, differed markedly between men and women in this study sample. Statistical analysis suggested that the effect of dietary fat on body fatness may be different in men compared to women. CONCLUSIONS: Sexual dimorphism in body fatness has important implications for both clinical and epidemiologic research of obesity. The possibility that diet may have differential effect on body fatness in men and women needs to be investigated.

Adipose Tissue↗
PubMed1999

Food price policy can favorably alter macronutrient intake in China.

The rapid change in diets, physical activity and body composition in low income countries has led to the coexistence of large pockets of undernutrition and overnutrition. Public health strategies for addressing this situation may be necessary, and price policy options are examined for China. Longitudinal dietary data collected in China in 1989-1993 on a sample of 5625 adults aged 20-45 y were examined. Three-day averages of food group consumption and nutrient intake were used in longitudinal statistical models to examine separately the effects of food prices on the decision to consume each food group and then the amount consumed. The effects of changes in six food prices on the consumption of each of six food groups, not just the food group whose price had changed, and on three macronutrients were estimated. The effects show large and significant price effects. If the joint effects of the nutrition transition are to be considered, then there are clear tradeoffs among which foods to tax and which to subsidize. Most important is the effect of prices in reducing fat intake of the rich but not adversely affecting protein intake for the poor. Increases in the prices of pork, eggs and edible oils are predicted to lower fat intake. Only increases in pork prices led to reduced protein intakes. This raises questions about earlier policy changes being implemented in China and provides insight into an important and controversial area for public health policy.

Adult↗
PubMed1998

[The impact of maternal education on the dietary and nutritional status of preschool children--a case study in 8 provinces of China].

This analysis is based on the data from China Health and Nutrition Survey in collaboration with University of North Carolina at Chapel Hill undertaken in 8 provinces of China from 1993 to 1996. Totally, 1098 mother-child pairs under age 6 were investigated. Descriptive analysis and stratified analysis are applied to investigate the impact of maternal education on the dietary and nutritional status of children. Both the crude analysis and after controlling for confounding variables, maternal education in the population remains statistically relevant to children's dietary and nutritional status. The proportion of low body weight and stunting children is the highest in the group with maternal education level being below preliminary school, the lowest in the group with education level being above high middle school. Moreover, in these three groups, the higher the level of maternal education, the greater the percentage of nutrients intake of China RDA, especially those from animal food. These results fully illustrate the importance of maternal education for the prevention of malnutrition in children.

Adult↗
PubMed1998

Measurement error in dietary data: implications for the epidemiologic study of the diet-disease relationship.

OBJECTIVES: To examine the effect of measurement error in dietary data on the relationship between diet and body mass index (BMI). To correct for the effect of measurement error on diet-BMI association by using replicate measurements of diet. The effect of measurement error on diet--BMI relationship was simulated, and its implications are discussed. DESIGN: Prospective study design. SETTING: The first and second China Health and Nutrition Survey conducted in 1989 and 1991, respectively. SUBJECTS: Three thousand, four hundred and seventy-nine adults age 20-45 y at the 1989 survey. METHODS: Statistical methods were used to demonstrate the effect of measurement error in dietary data on the diet-BMI association. RESULTS: By using the average of three replicate 24 h dietary recalls, the attenuation of diet-BMI association was reduced substantially. The regression coefficients of fat and energy intakes differed markedly from those computed by using only single measurement of diet. CONCLUSIONS: Measurement error in dietary data may significantly attenuate the diet-disease association. Where appropriate, specific emphasis may be needed to address the problem of measurement error in the study of diet-disease relationship.

Adult↗
PubMed1998

Changes in diet and physical activity affect the body mass index of Chinese adults.

OBJECTIVE: To examine the relationship between diet, particularly dietary fat intake, and body mass index (BMI). DESIGN: Prospective study of adults who participated in the 1989 and 1991 China Health and Nutrition Survey. SUBJECTS: 3484 adults aged 20-45 at baseline (1989) survey. MEASUREMENTS: Measurement of dietary intake with replicated 24 h dietary recalls. Anthropometric measurements. Measurements of physical activity, smoking habit and socio-economic factors. RESULTS: Change in fat intake was positively associated with change in BMI in men (beta=0.00036, P=0.0001), and change in physical activity level was inversely associated with change in BMI in women (beta=-0.12, P=0.02). Energy intake, physical activity and major socio-economic factors were related to BMI in cross-sectional analysis. CONCLUSIONS: Diet is becoming an increasingly important determinant of body weight in this population, where fat and energy consumption has been increasing steadily during the past decade.

Adult↗
PubMed1998

The nutrition transition and its health implications in lower-income countries.

OBJECTIVE: This article reviews information on the rapid changes in diet, activity and body composition that lower- and middle-income countries are undergoing and then examines some of the potential health implications of this transition. DESIGN AND SETTING: Data came from numerous countries and also from national food balance (FAOSTAT) and World Bank sources. Nationally representative and nationwide surveys are used. The nationally representative Russian Longitudinal Monitoring Surveys from 1992-96 and the nationwide China Health and Nutrition Survey from 1989-93 are examined in detail. RESULTS: Rapid changes in the structure of diet, in particular associated with urbanization, are documented. In addition, large changes in occupation types are documented. These are linked with rapid increases in adult obesity in Latin America and Asia. Some of the potential implications for adult health are noted. CONCLUSIONS: The rapid changes in diet, activity and obesity that are facing billions of residents of lower- and middle-income countries are cause for great concern. Linked with these changes will be a rapid increase in chronic diseases. Little to date has been done at the national level to address these problems.

Adult↗
PubMed1998

Trends in breakfast consumption for children in the United States from 1965-1991.

We examined breakfast consumption patterns and trends between 1965 and 1991 for children (1-10 y old) and adolescents (11-18 y old) in the United States. The analysis was undertaken by pooling nationally representative samples obtained from the Nationwide Food Consumption Surveys of 1965 and 1977-1978 and the 1989-1991 Continuing Survey of Food Intakes by Individuals. Breakfast consumption, defined as the consumption of food, beverage, or both between 0500 and 1000, was the focus of the trends analysis. Descriptive results indicated a decline in breakfast consumption between 1965 and 1991, particularly for older adolescents aged 15-18 y; the rates for boys and girls declined from 89.7% and 84.4%, respectively, in 1965 to 74.9% and 64.7%, respectively, in 1991. Multivariate results indicated that breakfast consumption declined predominantly because of behavioral changes and not the population's changing sociodemographic patterns. The nutritional quality of foods consumed at breakfast has improved since 1965, with significant shifts toward consumption of lower-fat milk and smaller changes in other food groups. The improvement over time in the quality of food consumed at breakfast, however, is offset by the large percentage of persons aged > or = 11 y who do not presently consume breakfast. Given the association of obesity with less frequent breakfast consumption and the rise in obesity among persons of this age group, a renewed emphasis on the importance of breakfast is warranted.

Adolescent↗
PubMed1998

Dietary fat intake does affect obesity!

There is a difference of opinion about whether the percentage of dietary fat plays an important role in the rising prevalence of overweight and in its treatment once it has developed. We believe that ample research from animal and clinical studies, from controlled trials, and from epidemiologic and ecologic analyses provides strong evidence that dietary fat plays a role in the development and treatment of obesity. A reduction in fat intake reduces the gap between total energy intake and total energy expenditure and thus is an effective strategy for reducing the present epidemic of obesity worldwide. A review of the results from 28 clinical trials that studied the effects of a reduction in the amount of energy from fat in the diet showed that a reduction of 10% in the proportion of energy from fat was associated with a reduction in weight of 16 g/d. We thus conclude that dietary fat plays a role in the development of obesity. To reduce the prevalence of obesity, there must be an increase in energy expenditure, a reduction in total energy intake, or both. This goal can be facilitated by reducing the amount of fat in the diet.

Animals↗
PubMed1998

Adolescent obesity increases significantly in second and third generation U.S. immigrants: the National Longitudinal Study of Adolescent Health.

Little is known concerning obesity patterns of ethnic subpopulations in the U.S. and the effects of acculturation on these patterns. Adolescent obesity, a major public health problem, has important health, social and economic consequences for the adolescent. The National Longitudinal Study of Adolescent Health survey is unique in the size of the adolescent sample and in its ability to provide large representative samples of Anglo, African-American, Hispanic and Asian-American adolescents. A nationally representative sample of 13,783 adolescents was studied. Measurements of weight and height collected in the second wave of the survey were used to study adolescent obesity. Multivariate logit techniques were used to provide an understanding of the ethnic, age, gender and intergenerational patterns of adolescent obesity. Comparisons are presented between the NHANES III results and those from the Adolescent Health Survey. The smoothed version of the NHANES I 85th percentile cut-off was used for the measure of obesity in this paper. For the total sample, 26.5% were obese. The rates were as follows: white non-Hispanics, 24.2%; black non-Hispanics, 30.9%; all Hispanics, 30.4%; and all Asian-Americans, 20.6%. Important variations within the Hispanic and Asian-American subpopulations are presented. The Chinese (15.3%) and Filipino (18.5%) samples showed substantially lower obesity than non-Hispanic whites. All groups showed more obesity among males than among females, except for blacks (27.4% for males and 34.0% for females). Asian-American and Hispanic adolescents born in the U.S. are more than twice as likely to be obese as are first generation residents of the 50 states.

Acculturation↗
PubMed1998

The obesity epidemic is a worldwide phenomenon.

Obesity is not just a disease of developed nations. Obesity levels in some lower-income and transitional countries are as high as or higher than those reported for the United States and other developed countries, and those levels are increasing rapidly. Shifts in diet and activity are consistent with these changes, but little systematic work has been done to understand all the factors contributing to these high levels. The goal of this review is to provide an understanding of the patterns and trends of obesity around the world and some of the major forces affecting these trends. Several nationally representative and nationwide surveys are discussed.

Diet↗
PubMed1998

[Impact of maternal income on the nutrients intake of preschool children--a case study in 8 provinces of China].

The data of this study are based on the project "China Health and Nutrition Survey" carried out in 8 provinces of China from 1989 to 1998 in collaboration with the University of North Carolina at Chapel Hill, USA. Totally, 1180 and 916 mother-child pairs aged 2-6 were investigated in 1991 and 1993 respectively. Descriptive and stratified analysis is applied to investigate the impact of maternal income on the nutrients intake of children. It is found that the nutrients intake of children in higher maternal income group is greater than that in lower maternal income group. After adjusting for family income, the results show that the more contribution of the mother's income to the family, the more nutrients intake of their children, especially in lower income families. It is illustrated that the income of mother may be more important for children's dietary status than that of other members of the family.

Animals↗
PubMed1997

The nutrition transition: new trends in the global diet.

Analyses of economic and food availability data for 1962-1994 reveal a major shift in the structure of the global diet marked by an uncoupling of the classic relationship between incomes and fat intakes. Global availability of cheap vegetable oils and fats has resulted in greatly increased fat consumption among low-income nations. Consequently, the nutrition transition now occurs at lower levels of the gross national product than previously, and is accelerated further by high urbanization rates. Data from Asian nations, where diet structure is rapidly changing, suggest that diets higher in fats and sweeteners are also more diverse and more varied. Given that preferences for palatable diets are a universal human trait, fat consumption may be governed not by physiological mechanisms but by the amount of fat available in the food supply. Whereas economic development has led to improved food security and better health, adverse health effects of the nutrition transition include growing rates of childhood obesity. The implications of these trends are explored.

Diet↗
PubMed1996

A comparison of dietary trends among racial and socioeconomic groups in the United States.

BACKGROUND: There may be dietary differences among racial and socioeconomic groups in the United States. METHODS: Using data from a representative sample of adults, we compared dietary trends among blacks and whites of varying socioeconomic status. We developed comparable measures of diet and of the consumption of macronutrients and food groups for 6061 participants in the 1965 Nationwide Food Consumption Surveys, 16,425 in the 1977-1978 Nationwide Food Consumption Surveys, and 9920 in the 1989-1991 Continuing Survey of Food Intake by Individuals (all conducted by the U.S. Department of Agriculture). The primary outcome was the score (range, 0 to 16) on the Diet Quality Index, a composite of eight food-and-nutrient-based recommendations from the National Academy of Sciences. A score of 4 or less was considered to indicate a relatively more healthful diet, and a value of 10 or more a relatively less healthful diet. RESULTS: Overall dietary quality improved in all groups, from a mean Diet Quality Index score of 7.4 in 1965 to 6.4 in 1989-1991. In 1965, blacks of low socioeconomic status and, to a lesser extent, whites of low socioeconomic status had better diets than whites of high socioeconomic status. By the 1989-1991 survey, the differences among racial and socioeconomic groups had narrowed. In 1965, 9.3 percent of whites of low socioeconomic status, 16.4 percent of blacks of low socioeconomic status, and 4.7 percent of whites of high socioeconomic status had mean scores of 4 or less. In the 1989-1991 survey the respective percentages were 19.9, 23.5, and 20.0. Fat consumption decreased in all groups. The consumption of fruits and vegetables varied little over time, except for an increase among blacks of medium and high socioeconomic status. The consumption of grains and legumes increased over time among whites of medium and high socioeconomic status and declined among blacks of low socioeconomic status. CONCLUSIONS: In 1965, there were large differences among groups in dietary quality, with whites of high socioeconomic status eating the least healthful diet, as measured by the index, and blacks of low socioeconomic status the most healthful. By the 1989-1991 survey, the diets of all groups had improved and were relatively similar.

Adult↗