A non-invasive assessment of skin carotenoid status through reflection spectroscopy is a feasible, reliable and potentially valid measure of fruit and vegetable consumption in a diverse community sample

Objective To assess the feasibility, reliability and validity of reflection spectroscopy (RS) to assess skin carotenoids in a racially diverse sample. Design Study 1 was a cross-sectional study of corner store customers (n 479) who completed the National Cancer Institute Fruit and Vegetable Screener as well as RS measures. Feasibility was assessed by examining the time it took to complete three RS measures, reliability was assessed by examining the variation between three RS measures, and validity was examined by correlation with self-reported fruit and vegetable consumption. In Study 2, validity was assessed in a smaller sample (n 30) by examining associations between RS measures and dietary carotenoids, fruits and vegetables as calculated from a validated FFQ and plasma carotenoids. Setting Eastern North Carolina, USA. Results It took on average 94·0 s to complete three RS readings per person. The average variation between three readings for each participant was 6·8 %. In Study 2, in models adjusted for age, race and sex, there were statistically significant associations between RS measures and (i) FFQ-estimated carotenoid intake (P<0·0001); (ii) FFQ-estimated fruit and vegetable consumption (P<0·010); and (iii) plasma carotenoids (P<0·0001).Conclusions RS is a potentially improved method to approximate fruit and vegetable consumption among diverse participants. RS is portable and easy to use in field-based public health nutrition settings. More research is needed to investigate validity and sensitivity in diverse populations

Associations between shopping patterns, dietary behaviors, and Geographic Information System-assessed store accessibility among small food store customers

Objective: To examine associations between Geographic Information Systems (GIS)-assessed accessibility to small food stores, shopping patterns, and dietary behaviors among small food store customers. Design: Residential addresses and customer shopping patterns (frequency of shopping, previous purchase of fruits and vegetables) were gathered through customer intercept surveys. Addresses were geocoded and GIS-assessed distance and driving time from the participants' residence to the store were calculated. Dietary status and behaviors were assessed using an objective non-invasive measure of skin carotenoids, the National Cancer Institute Fruit and Vegetable Screener, and items to assess sugary beverage intake. Associations between distance and driving time, demographics, shopping frequency, prior reported purchase of fruits and vegetables at the store, and dietary behaviors were examined. Setting: Small food stores (n=22) across North Carolina. Participants: Cross-sectional convenience samples of English-speaking customers aged 18 or older (n=692). Results: Participants living closer to the small store had lower income and formal education were more likely to be Black, more likely to have previously bought fruits and vegetables at the store, and more frequently shopped at the store. In adjusted models, skin carotenoids (n=644) were positively associated with distance to the store from home in miles (p = 0.01). Conclusions: Customers who lived closer to the stores were more frequent shoppers and more likely to have previously purchased fruits and vegetables at the store yet had lower skin carotenoids. These results support continued efforts to examine how to increase the availability and promotion of healthful foods at small food retail stores

Qualitative perspectives of the North Carolina healthy food small retailer program among customers in participating stores located in food deserts

Background: The North Carolina Healthy Food Small Retailer Program (NC HFSRP) was established through a policy passed by the state legislature to provide funding for small food retailers located in food deserts with the goal of increasing access to and sales of healthy foods and beverages among local residents. The purpose of this study was to qualitatively examine perceptions of the NC HFSRP among store customers. Methods: Qualitative interviews were conducted with 29 customers from five NC HFSRP stores in food deserts across eastern NC. Interview questions were related to shoppers’ food and beverage purchases at NC HFSRP stores, whether they had noticed any in-store efforts to promote healthier foods and beverages, their suggestions for promoting healthier foods and beverages, their familiarity with and support of the NC HFSRP, and how their shopping and consumption habits had changed since implementation of the NC HFSRP. A codebook was developed based on deductive (from the interview guide questions) and inductive (emerged from the data) codes and operational definitions. Verbatim transcripts were double-coded and a thematic analysis was conducted based on code frequency, and depth of participant responses for each code. Results: Although very few participants were aware of the NC HFSRP legislation, they recognized changes within the store. Customers noted that the provision of healthier foods and beverages in the store had encouraged them to make healthier purchase and consumption choices. When a description of the NC HFSRP was provided to them, all participants were supportive of the state-funded program. Participants discussed program benefits including improving food access in low-income and/or rural areas and making healthy choices easier for youth and for those most at risk of diet-related chronic diseases. Conclusions: Findings can inform future healthy corner store initiatives in terms of framing a rationale for funding or policies by focusing on increased food access among vulnerable populations

A four-year observational study to examine the dietary impact of the North Carolina Healthy Food Small Retailer Program, 2017–2020

Background: The North Carolina (NC) Healthy Food Small Retailer Program (HFSRP) was passed into law with a $250,000 appropriation (2016–2018) providing up to$25,000 in funding to small food stores for equipment to stock healthier foods and beverages. This paper describes an observational natural experiment documenting the impact of the HFSRP on store food environments, customers’ purchases and diets. Methods: Using store observations and intercept surveys from cross-sectional, convenience customer samples (1261 customers in 22 stores, 2017–2020; 499 customers in 7 HFSRP stores, and 762 customers in 15 Comparison stores), we examined differences between HFSRP and comparison stores regarding: (1) change in store-level availability, quality, and price of healthy foods/beverages; (2) change in healthfulness of observed food and beverage purchases (“bag checks”); and, (3) change in self-reported and objectively-measured (Veggie Meter®-assessed skin carotenoids) customer dietary behaviors. Differences (HFSRP vs. comparison stores) in store-level Healthy Food Supply (HFS) and Healthy Eating Index-2010 scores were assessed using repeated measure ANOVA. Intervention effects on diet were assessed using difference-in-difference models including propensity scores. Results: There were improvements in store-level supply of healthier foods/beverages within 1 year of program implementation (0 vs. 1–12 month HFS scores; p = 0.055) among HFSRP stores only. Comparing 2019 to 2017 (baseline), HFSRP stores’ HFS increased, but decreased in comparison stores (p = 0.031). Findings indicated a borderline significant effect of the intervention on self-reported fruit and vegetable intake (servings/day), though in the opposite direction expected, such that fruit and vegetable intake increased more among comparison store than HFSRP store customers (p = 0.05). There was no significant change in Veggie Meter®-assessed fruit and vegetable intake by customers shopping at the intervention versus comparison stores. Conclusions: Despite improvement in healthy food availability, there was a lack of apparent impact on dietary behaviors related to the HFSRP, which could be due to intervention dose or inadequate statistical power due to the serial cross-sectional study design. It may also be that individuals buy most of their food at larger stores; thus, small store interventions may have limited impact on overall eating patterns. Future healthy retail policies should consider how to increase intervention dose to include more product marketing, consumer messaging, and technical assistance for store owners

Comparing food web structures and dynamics across a suite of global marine ecosystem models

Dynamic Green Ocean Models (DGOMs) include different sets of Plankton Functional Types (PFTs) and equations, thus different interactions and food webs. Using four DGOMs (CCSM-BEC, PISCES, NEMURO and PlankTOM5) we explore how predator-prey interactions influence food web dynamics. Using each model's equations and biomass output, interaction strengths (direct and specific) were calculated and the role of zooplankton in modeled food webs examined. In CCSM-BEC the single size-class adaptive zooplankton preys on different phytoplankton groups according to prey availability and food preferences, resulting in a strong top-down control. In PISCES the micro- and meso-zooplankton groups compete for food resources, grazing phytoplankton depending on their availability in a mixture of bottom-up and top-down control. In NEMURO macrozooplankton controls the biomass of other zooplankton PFTs and defines the structure of the food web with a strong top-down control within the zooplankton. In PlankTOM5, competition and predation between micro- and meso-zooplankton along with strong preferences for nanophytoplankton and diatoms, respectively, leads to their mutual exclusion with a mixture of bottom-up and top-down control of the plankton community composition. In each model, the grazing pressure of the zooplankton PFTs and the way it is exerted on their preys may result in the food web dynamics and structure of the model to diverge from the one that was intended when designing the model. Our approach shows that the food web dynamics, in particular the strength of the predator-prey interactions, are driven by the choice of parameters and more specifically the food preferences. Consequently, our findings stress the importance of equation and parameter choice as they define interactions between PFTs and overall food web dynamics (competition, bottom-up or top-down effects). Also, the differences in the simulated food-webs between different models highlight the gap of knowledge for zooplankton rates and predator-prey interactions. In particular, concerted effort is needed to identify the key growth and loss parameters and interactions and quantify them with targeted laboratory experiments in order to bring our understanding of zooplankton at a similar level to phytoplankton