Workshop on Understanding the Relationship Between Food Insecurity (FIS) and Obesity Panel on Research Gaps (Nutrition)

Transcription

1 Workshop on Understanding the Relationship Between Food Insecurity (FIS) and Obesity Panel on Research Gaps (Nutrition) David H. Holben, PhD, RD, LD College of Health Sciences and Professions School of Applied Health Sciences and Wellness (Nutrition)

2 Ohio Univ., Athens, OH

3 Objectives (Nutrition) 1) What are the major research questions that need to be addressed to better understand the relationships between FIS and obesity from a nutrition perspective? 2) How do both the research and the policy communities integrate the disciplinary perspectives on these issues to better understand the relationship of FIS and obesity and design programs and policies to address these issues?

4 The Field of Nutrition Heterogeneous field. Research and practice. Bench to Bedside. Farm to Fork.

5 Obesity Berryman and Taylor, In press. Multifactorial disease. A combination of genetic, lifestyle, and environmental factors contribute to an accumulation of body fat that has serious negative health outcomes. Genes Epigenetics Methylation of cytosine residues Covalent modification of histones (e.g. acetylation phosphorylation,ubiquitylation) Activities of small interfering RNAs Genetic Expression Phenotype obesity Environment diet exercise chemical exposure etc.

6 Obesity Research Berryman and Taylor, In press. Increased rates of obesity cannot be solely attributed to genetic causes and suggests a more complex milieu at work. Key factors influencing the prevalence of obesity: Changes in lifestyle behaviors. Environmental factors.

7 Food Insecurity (FIS) Rose, 2010 Associations between FIS and various outcomes Weight status Cognitive development Mental health outcomes Other health outcomes

8 Conceptual Framework Rose,2010; Riley et al.,1999; Kim et al.,2008 Food Availability Food Access Food Utilization Health Outcomes Supply of food available to a community or region Ability of an individual or household to acquire food, either through market purchase or own production Process of converting food to nutrients

9 Nutritional State Adapted from National Research Council, 2006 Medical Conditions Physical, environmental, and personal factors FOOD INSECURITY Poor dietary intake Malnutrition Consequences (Chronic disease, impaired performance)

10 FIS Determinants/Cons. Adapted from National Research Council, 2006 Livelihood strategies Economic & social resources, functional limitations, and control Management strategies FOOD INSECURITY Hunger Dietary intake Poor nutritional status Distress and adverse family & social interactions Worry and Anxiety Deprivation and alienation Lack of wellbeing

11 FIS Conceptual Model (Alaimo, 2005) Livelihood strategies Economic & social resources, functional limitations, and control Management strategies FOOD INSECURITY Hunger Dietary intake Poor nutritional status Distress and adverse family & social interactions Worry and Anxiety Deprivation and alienation Lack of wellbeing

12 FIS Conceptual Model (Alaimo, 2005)

13 GAPS in Measurement FIS and Obesity Measures of Obesity by trained personnel. Measures of food insecurity using validated measures (18-item). Does the current measure of FIS fully capture the experience of FIS among children? Formative work is needed to validate child measures of FIS.

14 GAPS-Relationship? Is there a causal relationship between food insecurity and obesity? Food insecurity Obesity Food insecurity Obesity Food insecurity Obesity

15 Nutrition-related FIS and Obesity Research Primarily Descriptive Epidemiologic Research Studies Quantify extent and location of nutritionrelated problems within population. Suggest associations between FIS and weight status.

16 Relationship of FIS and Obesity? Is there a causal relationship between FIS and obesity? Considering Hill s Criteria for Causation: Experimental evidence through controlled experiments is lacking. Prospective, retrospective, longitudinal. Association is most convincing for women. Older adults Critical/sensitive periods of development

17 GAPS-Mediators What is/are the mediating mechanism(s)/factor(s) between food insecurity and obesity?

18 Conceptual Model (Alaimo, 2005)

19 Potential Mediating Mechanisms/Factors What are the potential mediating mechanisms/factors of FIS and obesity? Diet Quality (Diets may have adequate calories, but lack the qualities to promote health.) Caloric Intake Physical Activity

20 Potential Mediating Mechanisms/Factors Research Question Potential Mechanism What is the diet quality of those on a low food budget? Food groups (Low produce intake) Nutrients/nutrient density Food components (Intake of high levels of high fructose corn syrup) Dietary contaminants [Bisphenol A (BPA)] Food Insecurity Poor Diet Quality (e.g., poor produce intake) Obesity Example Policy Implications SNAP Rewards Produce Subsidies to Increase Availability and Access

21 Potential Mediating Mechanisms/Factors Research Question Potential Mechanism What is the caloric intake of those on a low food budget? Food Insecurity Increased Caloric Intake Obesity

22 Potential Mediating Mechanisms/Factors Does weight gain among individuals from food insecure households (who have low purchasing power) result from consuming inexpensive foods with high energy density when money is less available to spend on food? Does weight gain among individuals from food insecure households result from inconsistent access to food leading to periods of underconsumption, followed by compensatory overconsumption? Source: Wilde and Peterman, 2006

23 Potential Mediating Mechanisms/Factors Potential Mechanism Cyclic Purchasing Cyclic Consumption Gradual Weight Gain For individuals living in severely food insecure homes, do energy deficits offset the mechanism(s)/factor for weight gain seem among those from less food insecure households? Policy Implications SNAP Allocations (Monthly vs. Bi-monthly) Source: Wilde and Peterman, 2006

24 Potential Mediating Mechanisms/Factors Other ideas related to lifestyle? How does lifestyle influence dietary patterns and intake (e.g., circadian rhythm)? Measures of physical activity. Smoking?

25 Potential Mediating Integration of Disciplines Mechanisms/Factors The Cost of Eating Healthy Consumption (economic perspective, $) vs. Consumption (energy) Indicators of Stress and Dietary Quality/Hormonal Controls (e.g., cortisol)/physical Activity

26 Potential Mediating Mechanisms Integration of Disciplines Growing up poor and obesity in adulthood Do socioeconomic deprivation and associated early life stressors alter biological mechanisms that influence body weight?

27 Other Areas to Explore Reshaping the Food Environment Food Environments/Healthy Food Access Where do people get food? Taxes on sugar-sweetened beverages and junk foods, tax breaks for supermarkets to locate in food deserts, increased acceptance of SNAP at farmers markets. Natural Experiments that arise from policy changes. How do price and availability affect consumption/diet quality? Opportunity to engage and collaborate with urban/city/rural planners and geographers.

28 Nutrition Research Gaps Summary To better understand the relationships between FIS and obesity. Experimental evidence through controlled experiments should be conducted. Potential mediating mechanisms/factors should be explored, including diet quality and caloric intake. Understanding and integrating differing disciplinary perspectives are vital, as is designing programs and policies, to address these issues.

29 Thank you!