Biomedical subjects

Barry M Popkin

Publications and source records attributed to Barry M Popkin.

At least 37 records · Page 2Linked to original sources

PubMed2005

Using research on the obesity pandemic as a guide to a unified vision of nutrition.

OBJECTIVE: To focus on factors that play a major role in our rapid, global nutritional changes. DESIGN: A range of studies are summarised: these show how an understanding of social, economic and technological change at the global, national and community levels affects diet, activity, and body composition patterns and trends. These studies are used to demonstrate the value of the key global, national, community, household and individual factors that should define the field of nutrition. SETTING: The focus is global. RESULT: Large shifts have occurred in diet and in physical activity patterns--particularly in the last one or two decades of the twentieth century. These changes are reflected in nutritional outcomes such as changes in average stature, body composition and morbidity. Understanding the rapidity of these changes and the underlying factors at the global, national and community levels is critical for creating a science of nutrition that can prevent disease and sustain the health and integrity of humans. CONCLUSION: The vision of the nutrition field is one where scholars who work on many levels will intersect; equal weight in the nutrition profession will be provided to all dimensions as they are welcomed into the field of nutrition--particularly those that will directly or indirectly affect dietary patterns, physical activity patterns, and energetics. This vision of the nutrition field is one where scholars from a range of disciplines and perspectives meet to work together with the goal being a focus on improving nutritional status and the human condition.

Diet↗

PubMed2005

Overweight exceeds underweight among women in most developing countries.

BACKGROUND: It is generally believed that overweight is less prevalent than undernutrition in the developing world, particularly in rural areas, and that it is concentrated in higher socioeconomic status (SES) groups. OBJECTIVE: The purpose of this study was to examine patterns of adult female overweight and underweight in the developing world by using categories of urban or rural status and SES strata. DESIGN: Body mass index (BMI; in kg/m(2)) data collected in 36 countries from 1992 to 2000 by nationally representative cross-sectional surveys of women aged 20-49 y (n = 148579) were classified as indicating underweight (BMI < 18.5) and overweight (BMI >/= 25). Associations between the nutritional status of urban and rural women and each country's per capita gross national income (GNI) and level of urbanization were explored in the overall sample and among different SES groups. RESULTS: Overweight exceeded underweight in well over half of the countries: the median ratio of overweight to underweight was 5.8 in urban and 2.1 in rural areas. Countries with high GNIs and high levels of urbanization had not only high absolute prevalences of overweight but also small urban-rural differences in overweight and very high ratios of overweight to underweight. In the more-developed countries, overweight among low-SES women was high in both rural (38%) and urban (51%) settings. Even many poor countries, countries in which underweight persists as a significant problem, had fairly high prevalences of rural overweight. CONCLUSIONS: In most developing economies, prevalences of overweight in young women residing in both urban and rural areas are higher than those in underweight women, especially in countries at higher levels of socioeconomic development. Research is needed to assess male and child overweight to understand the dynamics facing these groups as well.

Adult↗

PubMed2004

Dietary fat and obesity: a review of animal, clinical and epidemiological studies.

The First Law of Thermodynamics provides a framework for understanding the imbalance between energy intake and expenditure that produces obesity, but it does not help understand the role of genetics, the regulation of food intake, the distribution of body fat, the mechanisms by which diets work or the mechanism by which portion control has gotten out of control. In animals, increasing dietary fat increases body fat, and it is unlikely that humans escape this important biological rule. In epidemiological studies, increasing dietary fat is associated with increased prevalence of obesity probably by increasing the intake of energy dense foods. In the National Weight Loss Registry, three things were associated with weight loss: continued monitoring of food intake, lowering dietary fat intake, and increased exercise. The relation of dietary fat is most evident when physical activity is low. The speed of adaptation to dietary fat is increased by exercise. When dietary fat is reduced, weight is lost, but weight loss eventually plateaus. The rate of weight loss during the initial phase is about 1.6 g/day for each 1% decrease in fat intake. When dietary fat is replaced with olestra to reduce fat intake from 33% to 25% in obese men, weight loss continues for about 9 months reaching a maximum of nearly 6% of body weight and a loss of 18% of initial body fat. In the control group with a 25% reduced-fat diet, weight loss stopped after 3 months and was regained over the next 6 months, indicating the difficulty of adhering to a conventional low-fat diet. Thus, dietary fat is an important contributor to obesity in some people.

Animal Experimentation↗

PubMed2004

The impact of socio-economic factors on functional status decline among community-dwelling older adults in China.

The purpose of this paper is to examine the impact of baseline socio-economic factors on functional status decline over a period of 3 years among a sample of Chinese older men and women, using the China Health and Nutrition Surveys of 1997 and 2000. In addition, the study tries to determine whether risk differentials by these socio-economic factors can be explained by other demographic, health-related and nutritional risk factors. The eligible study population was defined as women and men aged 55 years and over who at baseline were free from any form of disablement in activities of daily living (ADLs) or instrumental activities of daily living (IADL) tasks. Among subjects with complete data at followed-up (N = 976), the overall incidence proportions of any functional status decline, IADL only and ADL declines were 25.8%, 18.9% and 6.9%, respectively. Our study found that education is strongly and inversely associated with incidence of combined functional status decline and IADL only but not with the onset of ADL disability. Similarly, household income per capita was inversely associated with functional status decline and IADL disability incidence, with a clear dose-response relationship, even after adjustment for age and gender. However, multivariate analysis demonstrated that the latter association was highly confounded by other demographic factors, especially urban-rural area of residence. Using a combined measure of socio-economic status that includes years of education and household income per capita, the age and gender-adjusted odds ratio for functional status decline and belonging to lower SES class as compared to middle, upper middle and upper classes was 3.82 (95% CI: 2.15, 6.77) and 2.77 (95% CI: 1.52, 5.03) after further adjustment for urban-rural area of residence and living arrangements. Hence, there are wide socio-economic disparities in the functional health of older adults in China, although such disparities are more seen for IADL decline and are almost exclusively attributed to differentials in educational attainment. Finally, nutritional and health-related risk factors do not seem to act as intermediate factors in this association and hence further research should try to uncover other mechanisms by which SES affects changes in functional health among older adults in China.

Activities of Daily Living↗

PubMed2004

Contrasting socioeconomic profiles related to healthier lifestyles in China and the United States.

Health disparity by socioeconomic status has recently become an important public health concern. Socioeconomic status may affect health status through several pathways including lifestyle choices. The authors tested the link between socioeconomic status and lifestyle in China (in 1993) and in the United States (in 1994-1996), countries with high contrasts in development, to understand health discrepancy issues cross-nationally. Healthfulness of lifestyle was measured using the Lifestyle Index, a summary score that integrates four key lifestyle factors: diet, physical activity, smoking, and alcohol consumption. Income and education were used as indicators of socioeconomic status. In China, as socioeconomic status improved, lifestyle was less healthy (relative odds for the highest socioeconomic status group = 0.19, 95% confidence interval: 0.10, 0.35). Conversely, in the United States, higher socioeconomic status was related to a healthier lifestyle (relative odds for the highest socioeconomic status group = 3.81, 95% confidence interval: 2.94, 4.94). The contrasting relation between socioeconomic status and lifestyle depicts different phases of the lifestyle transition (changes in lifestyles accompanying economic development). The differences may in part explain why nutrition-related noncommunicable diseases are more prevalent in the developing world among people with a high socioeconomic status, whereas often the opposite is found in developed societies. Public health programs may benefit by advising each socioeconomic status group separately, while considering the country's level of development.

Adult↗

PubMed2004

Changes in beverage intake between 1977 and 2001.

OBJECTIVE: To examine American beverage consumption trends and causes. METHODS: Nationally representative data from the 1977-1978 Nationwide Food Consumption Survey, the 1989-1991 and 1994-1996 (also for children aged 2 to 9 years in 1998) Continuing Surveys of Food Intake by Individuals (CSFII), and 1999-2001 National Health and Nutrition Examination Survey were used in this study. The sample consisted of 73,345 individuals, aged >or=2 years. For each survey year, the percentage of total energy intake from meals and snacks was calculated separately for respondents aged 2 to 18 years, 19 to 39, 40 to 59, and >or=60. The percentage of energy intake by location (at home consumption or preparation, vending, store eaten out, restaurant/fast food, and school), as well as for specific beverages was computed separately for all age groups. The proportion consumed, mean portion size, and number of servings were calculated. RESULTS: For all age groups, sweetened beverage consumption increased and milk consumption decreased. Overall, energy intake from sweetened beverages increased 135% and was reduced by 38% from milk, with a 278 total calorie increase. These trends were associated with increased proportions of Americans consuming larger portions, more servings per day of sweetened beverage, and reductions in these same measures for milk. CONCLUSIONS: There is little research that has focused on the beneficial impacts of reduced soft drink and fruit drink intake. This would seem to be one of the simpler ways to reduce obesity in the United States.

Adolescent↗

PubMed2004

Longitudinal physical activity and sedentary behavior trends: adolescence to adulthood.

BACKGROUND: There is little national research on longitudinal patterns of physical activity and sedentary behavior in ethnically diverse teens as they transition to adulthood. METHODS: Longitudinal questionnaire data from U.S. adolescents enrolled in Wave I (1994-1995) and Wave III (2001) of the National Longitudinal Study of Adolescent Health (n =13,030) were analyzed in January 2004. Incidence, reversal, and maintenance of achieving five or more weekly bouts of moderate to vigorous physical activity (MVPA) and < or =14 hours of weekly TV and video viewing, computer/video game use (screen time) were assessed. Multinomial logistic regression models examined the likelihood of achieving five or more weekly sessions of MVPA week and < or =14 hours screen time per week as an adolescent and/or young adult, controlling for household income, parental education, age of adolescent, and seasonality. RESULTS: Of those achieving five or more weekly sessions of MVPA and < or =14 hours of weekly screen time as adolescents, few continued to achieve these favorable amounts of activity (4.4%) and screen time (37.0%) as adults. More failed to maintain these favorable amounts of activity (31.1%) and screen time (17.3%) into adulthood. Black versus white females were more likely to maintain less [corrected] favorable amounts of activity from adolescence to adulthood (odds ratio [OR]=3.09; 95% confidence interval [CI]=1.49-6.42), while black males (OR=1.50; CI=1.05-2.14) and females (OR=2.00; CI=1.40-2.87) were more likely than whites to maintain less (versus more) favorable screen time hours. CONCLUSIONS: The vast majority of adolescents do not achieve five or more bouts of moderate physical activity per week, and continue to fail to achieve this amount of activity into adulthood.

Adolescent↗

PubMed2004

The effect of participation in the WIC program on preschoolers' diets.

OBJECTIVE: To evaluate nutrient, food intake, and snacking behavior by participation in the WIC (Special Supplemental Nutrition Program for Women, Infants, and Children) program. STUDY DESIGN: Secondary data analysis of a nationally representative cross-sectional survey conducted by USDA in 1994 to 1996 and 1998. METHODS: Statistical analysis was performed correcting for sample design effects and weighting for children in two income groups (<130%, n=1772 and 130% to 185% of poverty, n=689). RESULTS: Among WIC participants, the prevalence of snacking was significantly lower (68%) compared with nonparticipants (72%) (chi(2)=5.9, P=.01). For those <130% of poverty, WIC had a beneficial effect on the intake of fat, carbohydrates, added sugar, and fruit from the total diet as well as on added sugar from snacks. These were independent of food stamp participation. For those with higher incomes, the beneficial effects were limited to added sugar, iron density, and fruit intake for the total diet. A similar significant effect of decreased added sugar intake from snacks was also seen. CONCLUSIONS: Our results are in line with previous research showing beneficial effects of WIC participation among preschoolers, primarily for nutrients targeted by the program. This study shows that the effect can reach beyond those targeted nutrients.

Child Nutritional Physiological Phenomena↗

PubMed2004

Understanding the role of mediating risk factors and proxy effects in the association between socio-economic status and untreated hypertension.

The association between socio-economic status (SES) and untreated hypertension varies according to a country's level of development and racial/ethnic group. We sought to confirm this variation in women from China and the United States (US) as well as to investigate the impact of SES on several mediating risk factors. We also investigate the extent to which SES explains racial/ethnic differences in untreated hypertension in the US. We used cross-sectional data from 1814 non-pregnant women in China (China Health and Nutrition Survey (CHNS), 1997) and 3266 non-pregnant women in the United States (National Health and Nutrition Examination Survey (NHANES III), 1988-1994) respectively. A variety of statistical modelling techniques was used to predict untreated hypertension as a function of several mediating factors and to simulate the impact of changes in SES. The age-adjusted prevalence of untreated hypertension was significantly higher (p<0.01) for low-income White and Black women compared to Mexican American or Chinese women. Untreated hypertension was not significantly associated with income or education in Mexican Americans or women in China. Obesity and light physical activity had the largest mediating effect on the association between SES and untreated hypertension for all racial/ethnic groups. However, this effect was not as strong as the proxy effect of income and education. SES did not completely explain racial/ethnic differences in hypertension in the US. While SES was more strongly associated with hypertension in Blacks than Whites, Blacks were still 1.97 (95% CI 1.47-2.64) times more likely to have untreated hypertension than Whites after adjusting for SES differences. The association between SES and untreated hypertension varied by country and racial/ethnic group. An important explanation for this variation was the differential effect of SES on mediating risk factors. SES disparities between Whites and Blacks in the US partly explain differences in the prevalence of untreated hypertension between these racial/ethnic groups.

Adult↗

PubMed2004

Rapid income growth adversely affects diet quality in China--particularly for the poor!

To study the impact of income change--specifically rapid income growth--on diet behavior over time and by socioeconomic level, we used data from a prospective study of China begun in 1989 (followed up in 1991, 1993 and 1997). The subpopulation used in this study included 5783 subjects aged 20-45 years old from 3129 households. Dietary intakes were measured using a combination of the weighing method and three consecutive 24-h recalls. Detailed income and price data were collected, and predicted household per capita income was used in multivariate longitudinal random-effects models that described the consumption of several food groups and nutrients. Income elasticity was used to measure the changes for the effects of income over time on (a) the probability of consuming any food and (b) the quantity of food consumed. The structure of the Chinese diet is shifting away from high-carbohydrate foods toward high-fat, high-energy density foods. The variation in the income effects that we uncovered indicated that important changes in income effects took place between 1989 and 1997, with the changes varying considerably by socioeconomic status. These shifts in income effects indicate that increased income might have affected diets and body composition in a detrimental manner to health, with those in low-income groups having the largest increase in detrimental effects due to increased income. Extrapolating from our estimates, higher income levels in the future could lead to the reversal of the health improvements achieved in the last two decades, if diet-related noncommunicable diseases cannot be controlled.

Adult↗

PubMed2004

A cross-national comparison of lifestyle between China and the United States, using a comprehensive cross-national measurement tool of the healthfulness of lifestyles: the Lifestyle Index.

BACKGROUND: Extensive studies have revealed the importance of a healthy lifestyle and the role of each lifestyle factor in health. However, lifestyle factors have rarely been studied simultaneously. The authors propose an integrated approach to summarize total healthfulness of lifestyles and to enhance understanding of lifestyle patterns across countries. METHODS: The authors created an overall measure of lifestyle called the Lifestyle Index (LI), integrating diet, physical activity, smoking, and alcohol use to provide a global tool of monitoring healthfulness and patterns of lifestyles. Using the LI, the authors conducted a cross-national comparison between China (n = 8352) and the United States (n = 9750). RESULTS: The LI effectively reflected the healthfulness of lifestyle components in both countries. The mean of the LI scores was slightly higher in China than the US. Scores of diet quality, physical activity, and smoking were higher in China, but scores of alcohol behavior were higher in the US. Similar lifestyle patterns but different unhealthy behaviors were identified in these countries. CONCLUSIONS: An assessment of total healthfulness of lifestyles and a better understanding of lifestyle patterns across countries using the LI can provide practical guidance to developing and targeting public health promotion activities to improve global public health.

Adult↗

PubMed2004

Consumption of high-fructose corn syrup in beverages may play a role in the epidemic of obesity.

Obesity is a major epidemic, but its causes are still unclear. In this article, we investigate the relation between the intake of high-fructose corn syrup (HFCS) and the development of obesity. We analyzed food consumption patterns by using US Department of Agriculture food consumption tables from 1967 to 2000. The consumption of HFCS increased > 1000% between 1970 and 1990, far exceeding the changes in intake of any other food or food group. HFCS now represents > 40% of caloric sweeteners added to foods and beverages and is the sole caloric sweetener in soft drinks in the United States. Our most conservative estimate of the consumption of HFCS indicates a daily average of 132 kcal for all Americans aged > or = 2 y, and the top 20% of consumers of caloric sweeteners ingest 316 kcal from HFCS/d. The increased use of HFCS in the United States mirrors the rapid increase in obesity. The digestion, absorption, and metabolism of fructose differ from those of glucose. Hepatic metabolism of fructose favors de novo lipogenesis. In addition, unlike glucose, fructose does not stimulate insulin secretion or enhance leptin production. Because insulin and leptin act as key afferent signals in the regulation of food intake and body weight, this suggests that dietary fructose may contribute to increased energy intake and weight gain. Furthermore, calorically sweetened beverages may enhance caloric overconsumption. Thus, the increase in consumption of HFCS has a temporal relation to the epidemic of obesity, and the overconsumption of HFCS in calorically sweetened beverages may play a role in the epidemic of obesity.

Adolescent↗

PubMed2004

Five-year obesity incidence in the transition period between adolescence and adulthood: the National Longitudinal Study of Adolescent Health.

BACKGROUND: No nationally representative longitudinal data have been analyzed to evaluate the incidence of obesity in the transition between adolescence and adulthood. OBJECTIVE: The objective was to examine dynamic patterns of change in obesity among white, black, Hispanic, and Asian US teens as they transitioned to young adulthood. DESIGN: We used nationally representative, longitudinally measured height and weight data collected from US adolescents enrolled in wave II (1996; ages 13-20 y) and wave III (2001; 19-26 y) of the National Longitudinal Study of Adolescent Health (n = 9795). Obesity incidence was defined on the basis of International Obesity Task Force (IOTF) cutoffs (wave II), which link childhood body mass index (BMI) centiles to adult cutoffs (BMI > or = 30; wave III), for comparability between adolescence and adulthood. In addition, the more commonly used cutoff of BMI > or = 95th percentile for age- and sex-specific cutoffs from the 2000 Centers for Disease Control and Prevention growth charts for adolescents (wave II) were compared with adult cutoffs (BMI > or = 30; wave III). RESULTS: On the basis of the IOTF cutoffs, obesity incidence over the 5-y study period was 12.7%; 9.4% of the population remained obese and 1.6% shifted from obese to nonobese. Obesity incidence was especially high in non-Hispanic black (18.4%) females relative to white females. The prevalence of obesity increased from 10.9% in wave II to 22.1% in wave III, and extreme obesity was 4.3% at wave III on the basis of a BMI > or = 40. CONCLUSIONS: During a 5-y transitional period between adolescence and young adulthood, the proportion of adolescents becoming and remaining obese into adulthood was very high. This upward trend is likely to continue. Effective preventive and treatment efforts are critically needed.

Adolescent↗

PubMed2004

Within- and between-person variation in nutrient intakes of Russian and U.S. children differs by sex and age.

Within- and between-person variation in nutrient intake has been characterized in different adult populations, but little is known of country, age, or sex differences among children. The objectives of this study were as follows: 1) to describe the mean intake, within- and between-individual CV and variance ratios of nutrient intake among children ages 9-18 y old in Russia and the United States in 1996; 2) to compare the age and sex-related differences in nutrient intake variance within and between countries; and 3) to hypothesize about the feasibility of using within-individual variance estimates from one nationally representative sample to adjust the usual intake distributions in another nationally representative sample. Mean intakes of all nutrients except magnesium were significantly higher among U.S. children (P < 0.001); within-person variation was higher among the U.S. children, possibly indicating greater access to a wide array of foods. Strong differentials existed in variance components by sex in both countries, although not in the same direction, and differed by age in U.S. girls. Ratios of within- to between-person variance in 8 of 11 nutrients were lower among Russian (range: 0.9-1.6) than U.S. children (range: 1.4-1.7), suggesting that day-to-day bias may not affect Russian dietary recalls as strongly as in the United States. Researchers are encouraged to use these estimates to conduct sensitivity analyses of usual intake distributions in their own data when multiple days of data collection are not feasible.

Adolescent↗

PubMed2004

The nutrition transition: an overview of world patterns of change.

This paper examines the speed of change in diet, activity, and obesity in the developing world, and notes potential exacerbating biological relationships that contribute to differences in the rates of change. The focus is on lower- and middle-income countries of Asia, Africa, the Middle East, and Latin America. These dietary, physical activity, and body composition changes are occurring at great speed and at earlier stages of these countries' economic and social development. There are some unique issues that relate to body composition and potential genetic factors that are also explored, including potential differences in body mass index (BMI)--disease relationships and added risks posed by high levels of poor fetal and infant growth patterns. In addition there is an important dynamic occurring--the shift in the burden of poor diets, inactivity and obesity from the rich to the poor. The developing world needs to give far greater emphasis to addressing the prevention of the adverse health consequences of this shift to the nutrition transition stage of the degenerative diseases.

Body Composition↗

PubMed2004

Fatty acids in Chinese edible oils: value of direct analysis as a basis for labeling.

Edible oil is an important element in the diet of most transitional countries; nevertheless, little is known about the fatty acid composition of these oils. We examined the consumption of edible oils and the fatty acid composition of these oils obtained from a market survey conducted in seven Chinese provinces and in Beijing. Three days of measured household food intake from the 1997 China Health and Nutrition Survey households provided data on the consumption of edible oils. Edible oils sold in the capital cities of eight provinces were purchased. One hundred twenty-six samples, representing 14 different oils according to their labels, were assayed for their fatty acid content in 2001. Fatty acids were analyzed by standard gas chromatographic methods. More than 76% of households in China consume edible oil, providing an average of 29.6 g of edible oil per day to persons aged two years or older. Rapeseed was consumed by one-quarter of individuals. Rapeseed is rich in C22:1n9 cis (erucic acid). About 33% of edible oils differed from their labeled identification. Rapeseed oil, identified by the presence of C22:1n9 (erucic acid), was most frequently not labeled as such. In another 28% of the samples, trans isomers of linolenic acid were detected. Deviations from the label identification were more common in southern than in northern provinces. Regulations requiring complete labeling of mixed edible oils in China might help prevent unintentional consumption of fatty acids associated with adverse health outcomes. In particular, consumption of erucic acid and trans fatty acids might be reduced. The results suggest the need for closer control of food oil labeling in China, especially in the South.

China↗

PubMed2004

The burden of disease from undernutrition and overnutrition in countries undergoing rapid nutrition transition: a view from Brazil.

On the basis of 3 comparable population-based surveys conducted in Brazil, we identified clear changes in the relative magnitude of women's undernutrition and overnutrition. In 1975, there were almost 2 cases of underweight to 1 case of obesity, whereas in 1997, there were more than 2 cases of obesity to 1 case of underweight. In 1997, Brazilian low-income women were significantly more susceptible than high-income women to both underweight and obesity.

Adult↗

PubMed2004

Length of hospital stays among obese individuals.

OBJECTIVES: We examined lengths of hospital stay among individuals categorized according to weight status. METHODS: We used data from the First National Health and Nutrition Examination Survey Epidemiologic Followup Survey to estimate length-of-stay differences. RESULTS: Individuals with body mass indexes (BMIs) of 35 kg/m2 or above, those with BMIs of 30 to 34 kg/m2, and those with BMIs of 25 to 29 kg/m2 had crude length-of-stay rates greater than those of normal-weight individuals. Association between BMI and length of stay varied over time. CONCLUSIONS: Obese individuals experience longer hospital stays than normal-weight individuals.

Adult↗