Nathan R. Mitchell

Worksite Environment Intervention to Prevent Obesity Among Metropolitan Transit Workers

OBJECTIVE The results of an 18-month worksite intervention to prevent obesity among metropolitan transit workers are reported. METHODS Four garages in a major metropolitan area were randomized to intervention or control groups. Data were collected during the fall of 2005 prior to the start of the intervention and during the fall of 2007, after the intervention ended. Intervention program components at the garage included enhancement of the physical activity facilities, increased availability of and lower prices on healthy vending machine choices, and group behavioral programs. Mixed model estimates from cross-sectional and cohort samples were pooled with weights inverse to the variance of their respective estimates of the intervention effects. RESULTS Measurement participation rates were 78% at baseline and 74% at follow-up. The intervention effect on garage mean BMI change was not significant (-0.14 kg/m(2)). Energy intake decreased significantly, and fruit and vegetable intake increased significantly in intervention garages compared to control garages. Physical activity change was not significant. CONCLUSION Worksite environmental interventions for nutrition and physical activity behavior change may have limited impact on BMI among transit workers who spend most of their workday outside the worksite.

Pricing and availability intervention in vending machines at four bus garages

Objective: To evaluate the effects of lowering prices and increasing availability on sales of healthy foods and beverages from 33 vending machines in 4 bus garages as part of a multicomponent worksite obesity prevention intervention. Methods: Availability of healthy items was increased to 50% and prices were lowered at least 10% in the vending machines in two metropolitan bus garages for an 18-month period. Two control garages offered vending choices at usual availability and prices. Sales data were collected monthly from each of the vending machines at the four garages. Results: Increases in availability to 50% and price reductions of an average of 31% resulted in 10% to 42% higher sales of the healthy items. Employees were mostly price responsive for snack purchases. Conclusions: Greater availability and lower prices on targeted food and beverage items from vending machines was associated with greater purchases of these items over an 18-month period. Efforts to promote healthful food purchases in worksite settings should incorporate these two strategies.

Household Obesity Prevention: Take Action—a Group-Randomized Trial

The purpose of the present study was to evaluate an intervention to prevent weight gain among households (HHs) in the community. Ninety HHs were randomized to intervention or control group for 1 year. Intervention consisted of six face‐to‐face group sessions, placement of a television (TV) locking device on all home TVs, and home‐based intervention activities. Measures were collected in person at baseline and 1 year. Weight, height, eating behaviors, physical activity (PA), and TV viewing were measured among HH members ages ≥12 years. Follow‐up rate at 1 year was 96%. No significant intervention effects were observed for change in HH BMI‐z score. Intervention HHs significantly reduced TV viewing, snacks/sweets intake, and dollars per person spent eating out, and increased (adults only) PA and self‐weighing frequency compared with control HHs. A 1 year obesity prevention intervention targeting entire HHs was effective in reducing TV viewing, snack/sweets intake and eating out purchases. Innovative methods are needed to strengthen the home food environment intervention component. Longer intervention durations also need to be evaluated.

Household income differences in food sources and food items purchased

BackgroundThe present study examined income-related household food purchases among a sample of 90 households from the community.MethodsAnnotated food purchase receipts were collected for a four-week period by the primary household shopper. Receipt food source and foods items were classified into specific categories, and food quantities in ounces were recorded by research staff. For home sources, a limited number of food/beverage categories were recorded. For eating out sources, all food/beverage items were recorded. Median monthly per person dollars spent and per person ounces purchased were computed. Food sources and food categories were examined by household income tertile.Subjects and SettingA community-based sample of 90 households.ResultsHigher income households spent significantly more dollars per person per month from both home and eating out sources compared with lower income households (

HealthWorks: results of a multi-component group-randomized worksite environmental intervention trial for weight gain prevention

163 versus

Annotated receipts capture household food purchases from a broad range of sources

100, p < .001). Compared with lower income households, higher income households spent significantly more home source dollars on both fruits/vegetables (21.5 versus 10.2, p < .001) and sweets/snacks (17.3 versus 8.3, p < .001), but did not differ on home dollars spent on sugar sweetened beverages (2.0 versus 1.7, p < .46). The proportion of home beverages that were sugar sweetened beverages was significantly higher among lower income households (45% versus 26%, p < .01). Within eating out sources, lower income households spent a significantly greater percent of dollars per person at carry out places (54% versus 37%, p < .01). No income differences were observed for dollars spent at discount grocery stores, small grocery stores or convenience stores.ConclusionsHigher income households spent more money on both healthy and less healthy foods from a wide range of sources. Lower income households spent a larger proportion of their eating out dollars at carry out places, and a larger proportion of their home beverage purchases were sugar sweetened beverages.

Portion size effects on weight gain in a free living setting

BackgroundU.S. adults are at unprecedented risk of becoming overweight or obese, and most scientists believe the primary cause is an obesogenic environment. Worksites provide an opportunity to shape the environments of adults to reduce obesity risk. The goal of this group-randomized trial was to implement a four-component environmental intervention at the worksite level to positively influence weight gain among employees over a two-year period. Environmental components focused on food availability and price, physical activity promotion, scale access, and media enhancements.MethodsSix worksites in a U.S. metropolitan area were recruited and randomized in pairs at the worksite level to either a two-year intervention or a no-contact control. Evaluations at baseline and two years included: 1) measured height and weight; 2) online surveys of individual dietary intake and physical activity behaviors; and 3) detailed worksite environment assessment.ResultsMean participant age was 42.9 years (range 18-75), 62.6% were women, 68.5% were married or cohabiting, 88.6% were white, 2.1% Hispanic. Mean baseline BMI was 28.5 kg/m2 (range 16.9-61.2 kg/m2). A majority of intervention components were successfully implemented. However, there were no differences between sites in the key outcome of weight change over the two-year study period (p = .36).ConclusionsBody mass was not significantly affected by environmental changes implemented for the trial. Results raise questions about whether environmental change at worksites is sufficient for population weight gain prevention.Trial RegistrationClinicalTrials.gov: NCT00708461

Questionnaire and laboratory measures of eating behavior. Associations with energy intake and BMI in a community sample of working adults

BackgroundAccurate measurement of household food purchase behavior (HFPB) is important for understanding its association with household characteristics, individual dietary intake and neighborhood food retail outlets. However, little research has been done to develop measures of HFPB. The main objective of this paper is to describe the development of a measure of HFPB using annotated food purchase receipts.MethodsHouseholds collected and annotated food purchase receipts for a four-week period as part of the baseline assessment of a household nutrition intervention. Receipts were collected from all food sources, including grocery stores and restaurants. Households (n = 90) were recruited from the community as part of an obesity prevention intervention conducted in 2007–2008 in Minneapolis, Minnesota, USA. Household primary shoppers were trained to follow a standardized receipt collection and annotation protocol. Annotated receipts were mailed weekly to research staff. Staff coded the receipt data and entered it into a database. Total food dollars, proportion of food dollars, and ounces of food purchased were examined for different food sources and food categories. Descriptive statistics and correlations are presented.ResultsA total of 2,483 receipts were returned by 90 households. Home sources comprised 45% of receipts and eating-out sources 55%. Eating-out entrees were proportionally the largest single food category based on counts (16.6%) and dollars (

Snacking Behaviors, Diet Quality, and Body Mass Index in a Community Sample of Working Adults

106 per month). Two-week expenditures were highly correlated (r = 0.83) with four-week expenditures.ConclusionReceipt data provided important quantitative information about HFPB from a wide range of sources and food categories. Two weeks may be adequate to reliably characterize HFPB using annotated receipts.

Energy density and weight change in a long-term weight-loss trial

Examine the effect of weekday exposure over 6 months to different lunch sizes on energy intake and body weight in a free‐living sample of working adults.