Lisa M. Powell

Availability of Physical Activity–Related Facilities and Neighborhood Demographic and Socioeconomic Characteristics: A National Study

OBJECTIVES We examined associations between neighborhood demographic characteristics and the availability of commercial physical activity-related outlets by zip code across the United States. METHODS Multivariate analyses were conducted to assess the availability of 4 types of outlets: (1) physical fitness facilities, (2) membership sports and recreation clubs, (3) dance facilities, and (4) public golf courses. Commercial outlet data were linked by zip code to US Census Bureau population and socioeconomic data. RESULTS Results showed that commercial physical activity-related facilities were less likely to be present in lower-income neighborhoods and in neighborhoods with higher proportions of African American residents, residents with His-panic ethnicity, and residents of other racial minority backgrounds. In addition, these neighborhoods had fewer such facilities available. CONCLUSIONS Lack of availability of facilities that enable and promote physical activity may, in part, underpin the lower levels of activity observed among populations of low socioeconomic status and minority backgrounds.

CONSUMPTION PATTERNS OF SUGAR SWEETENED BEVERAGES IN THE UNITED STATES

BACKGROUND Few previous studies have investigated consumption distributions of sugar-sweetened beverages (SSBs) over time and individual-level associations despite recent interest in SSBs regarding obesity control. OBJECTIVE To assess consumption patterns and individual-level associations. DESIGN Trend and cross-sectional analyses of 24-hour dietary recall data and demographic characteristics and socioeconomic status (SES) drawn from National Health and Nutrition Examination Survey (1999-2000, 2001-2002, 2003-2004, 2005-2006, and 2007-2008) data. PARTICIPANTS/SETTING Children (aged 2 to 11 years, n=8,627), adolescents (aged 12 to 19 years, n=8,922), young adults (aged 20 to 34 years, n=5,933), and middle-aged and elder adults (aged ≥35 years, n=16,456). STATISTICAL ANALYSES PERFORMED Age-stratified regression analyses for SSBs overall and by subtypes. RESULTS The prevalence of heavy total SSB consumption (≥500 kcal/day) increased among children (4% to 5%) although it decreased among adolescents (22% to 16%) and young adults (29% to 20%). Soda was the most heavily consumed SSB in all age groups except for children. Prevalence of soda consumption decreased, whereas heavy sports/energy drink consumption tripled (4% to 12%) among adolescents. Black children and adolescents showed higher odds of heavy fruit drink consumption (odds ratios 1.71 and 1.67) than whites. Low-income children had a higher odds of heavy total SSB consumption (odds ratio 1.93) and higher energy intake from total SSBs and fruit drinks (by 23 and 27 kcal/day) than high-income children. Adolescents with low- vs high-educated parents had higher odds of heavy total SSB consumption (odds ratio 1.28) and higher energy intake from total SSBs and soda (by 27 and 21 kcal/day). Low vs high SES was associated with a higher odds of heavy consumption of total SSBs, soda, and fruit drinks among adults. CONCLUSIONS Prevalence of soda consumption fell, but consumption of nontraditional SSBs rose. Heterogeneity of heavy consumption by SSB types across racial/ethnic subpopulations and higher odds of heavy SSB consumption among low-SES populations should be considered in targeting policies to encourage healthful beverage consumption.

Assessing the potential effectiveness of food and beverage taxes and subsidies for improving public health: a systematic review of prices, demand and body weight outcomes

Taxes and subsidies are increasingly being considered as potential policy instruments to incentivize consumers to improve their food and beverage consumption patterns and related health outcomes. This study provided a systematic review of recent U.S. studies on the price elasticity of demand for sugar‐sweetened beverages (SSBs), fast food, and fruits and vegetables, as well as the direct associations of prices/taxes with body weight outcomes. Based on the recent literature, the price elasticity of demand for SSBs, fast food, fruits and vegetables was estimated to be −1.21, −0.52, −0.49 and −0.48, respectively. The studies that linked soda taxes to weight outcomes showed minimal impacts on weight; however, they were based on existing state‐level sales taxes that were relatively low. Higher fast‐food prices were associated with lower weight outcomes particularly among adolescents, suggesting that raising prices would potentially impact weight outcomes. Lower fruit and vegetable prices were generally found to be associated with lower body weight outcomes among both low‐income children and adults, suggesting that subsidies that would reduce the cost of fruits and vegetables for lower‐socioeconomic populations may be effective in reducing obesity. Pricing instruments should continue to be considered and evaluated as potential policy instruments to address public health risks.

Nutritional Content of Television Food Advertisements Seen by Children and Adolescents in the United States

OBJECTIVE. In light of the high rates of child and adolescent obesity, we examined the nutritional content of food advertising seen by American children and adolescents. METHODS. We drew samples of top-rated television shows by using ratings data to examine the nutritional content for fat, saturated fat, sugar, sodium, and fiber of food-product advertisements seen on television by both children and adolescents. Food products were examined in aggregate and by 5 separate categories that included cereal, sweets, snacks, drinks, and other food products. For 2- to 11-year-olds and 12- to 17-year-olds, respectively, a sample of 50351 and 47955 30-second-equivalent food-product advertisements and their related nutritional content were weighted by television ratings data to provide actual exposure measures of the nutritional content of food advertising seen by children and adolescents. RESULTS. Study results showed that 97.8% and 89.4% of food-product advertisements viewed by children 2 to 11 years old and adolescents 12 to 17 years old, respectively, were high in fat, sugar, or sodium. On average, 46.1% and 49.1% of total calories among the products advertised came from sugar in the advertisements seen by these respective age groups. A total of 97.6% of cereal advertisements seen by children 2 to 11 years old were for high-sugar cereals. No substantial differences were found in the nutritional content of advertisements seen by black and white children 2 to 11 years old. However, a slightly higher proportion of food advertisements in general and across all food-product categories seen by black versus white adolescents were for high-sugar products. CONCLUSION. The overwhelming majority of food-product advertisements seen on television by American children and adolescents are of poor nutritional content.

Soda Taxes, Soft Drink Consumption, And Children’s Body Mass Index

Taxes on sugar-sweetened beverages have been proposed to combat obesity. Using data on state sales taxes for soda and individual-level data on children, we examine whether small taxes are likely to change consumption and weight gain or whether larger tax increases would be needed. We find that existing taxes on soda, which are typically not much higher than 4 percent in grocery stores, do not substantially affect overall levels of soda consumption or obesity rates. We do find, however, that subgroups of at-risk children--children who are already overweight, come from low-income families, or are African American--may be more sensitive than others to soda taxes, especially when soda is available at school. A greater impact of these small taxes could come from the dedication of the revenues they generate to other obesity prevention efforts rather than through their direct effect on consumption.

Fast-Food and Full-Service Restaurant Consumption Among Children and Adolescents: Effect on Energy, Beverage, and Nutrient Intake

OBJECTIVE To examine the effect of fast-food and full-service restaurant consumption on total energy intake, dietary indicators, and beverage consumption. DESIGN Individual-level fixed-effects estimation based on 2 nonconsecutive 24-hour dietary recalls. SETTING Nationally representative data from the 2003-2004, 2005-2006, and 2007-2008 National Health and Nutrition Examination Survey. PARTICIPANTS Children aged 2 to 11 years (n = 4717) and adolescents aged 12 to 19 years (n = 4699). MAIN OUTCOME MEASURES Daily total energy intake in kilocalories; intake of grams of sugar, total fat, saturated fat, and protein and milligrams of sodium; and total grams of sugar-sweetened beverages, regular soda, and milk consumed. RESULTS Fast-food and full-service restaurant consumption, respectively, was associated with a net increase in daily total energy intake of 126.29 kcal and 160.49 kcal for children and 309.53 kcal and 267.30 kcal for adolescents and with higher intake of regular soda (73.77 g and 88.28 g for children and 163.67 g and 107.25 g for adolescents) and sugar-sweetened beverages generally. Fast-food consumption increased intake of total fat (7.03-14.36 g), saturated fat (1.99-4.64 g), and sugar (5.71-16.24 g) for both age groups and sodium (396.28 mg) and protein (7.94 g) for adolescents. Full-service restaurant consumption was associated with increases in all nutrients examined. Additional key findings were (1) adverse effects on diet were larger for lower-income children and adolescents and (2) among adolescents, increased soda intake was twice as large when fast food was consumed away from home than at home. CONCLUSION Fast-food and full-service restaurant consumption is associated with higher net total energy intake and poorer diet quality.

Food prices, access to food outlets and child weight

This study examines the importance of food prices and restaurant and food store outlet availability for child body mass index (BMI). We use the 1998, 2000 and 2002 waves of the child-mother merged files from the 1979 cohort of the National Longitudinal Survey of Youth combined with fruit and vegetable and fast food price data obtained from the American Chamber of Commerce Researchers Association and outlet density data on fast food and full-service restaurants and supermarkets, grocery stores and convenience stores obtained from Dun & Bradstreet. Using a random effects estimation model, we found that a 10% increase in the price of fruits and vegetables was associated with a 0.7% increase in child BMI. Fast food prices were not found to be statistically significant in the full sample but were weakly negatively associated with BMI among adolescents with an estimated price elasticity of -0.12. The price estimates were robust to whether we controlled for outlet availability based on a per capita or per land area basis; however, the association between food outlets and child BMI differed depending on the definition. The associations of fruit and vegetable and fast food prices with BMI were significantly stronger both economically and statistically among low- versus high-socioeconomic status children. The estimated fruit and vegetable and fast food price elasticities were 0.14 and -0.26, respectively, among low-income children and 0.09 and -0.13, respectively, among children with less educated mothers.

The Impact of Child Care Cost on the Labour Supply of Married Mothers: Evidence from Canada

This paper provides estimates for Canada of the impact of childcare costs on the labor supply of married mothers. This is done by linking two microdata sources: the 1988 Canadian National Child Care Survey and the 1988 Labour Market Activity Survey. The key results show that the market wage and childcare costs have, respectively, a significant positive and negative impact on both hours of work and the labor-force-participation decision by married mothers. The childcare cost elasticities for labor force participation and hours of work are reported to be -0.38 and -0.32, respectively.

The association of fast food, fruit and vegetable prices with dietary intakes among US adults : Is there modification by family income?

We examined the effects of prices of fast foods and fruits and vegetables on dietary intake, body mass index (BMI) and obesity risks and whether the associations varied across groups according to their family income. Data from the US Department of Agriculture Continuing Survey of Food Intakes by Individuals (CSFII 1994-96) for 7331 individuals aged 20-65 years with complete data on two 24-h recalls were used. We computed two food price indices (FFPI and FVPI) which were linked to individuals through geocoded identifiers. Main outcomes included dietary intakes of energy, selected nutrients and food groups, fast food consumption, and diet quality measured using two indices (HEI and aMED), BMI and obesity. Interaction terms between key variables were tested in regression analyses and in further stratified analysis by family income. Higher fast food price indices (FFPIs) were associated with higher fiber intake, lower saturated fat, and better overall diet quality as measured by aMED. FVPI was positively associated with improved dietary quality as well as in terms of lower cholesterol and sodium intakes, improved HEI and lower BMI. Most of these associations showed homogeneous strengths across income groups as evidenced by a non-significant FFPIxPIR or FVPIxPIR interaction term (p>0.10). While increasing FFPI by 1 standard deviation was only borderline protective against fast food consumption, its association with other binary outcomes that were considered was non-significant. In contrast, FVPI was protective against obesity, particularly among the near poor. It was also associated with improved aMED score. Analyses of these national data suggest that changing fast food and fruit and vegetable prices may affect peoples dietary quality and to some extent their adiposity, although the present study is limited by the available food price data.

Field validation of secondary commercial data sources on the retail food outlet environment in the U.S.

This study used direct field observations with interior assessments of outlets to validate food store and restaurant data from two commercial business lists conditional on classification of outlet type, including supermarkets, grocery stores, convenience stores, full-service restaurants and fast food restaurants. The study used a stratified random sample that included 274 urban census tracts across 9 counties from the Chicago Metropolitan Statistical Area (MSA) and 46 suburban and 61 rural census tracts across 13 counties from a 50-mile buffer surrounding the MSA. Results showed that agreement between the field observations and the commercial business lists for the food store and restaurant outlets was generally moderate (ranging from fair to good). However, when the listed data were validated based on an exact classification match, agreement was only fair (ranging from poor to moderate) and, in particular, poor for fast food restaurants. The study also found that agreement levels for some outlet types differed by tract characteristics. Commercial databases must be used with caution as substitutes for on the ground data collection.