Environmental Intervention for Preventing Overweight and Obesity

Part 3: Background outlines the research basis for using an environmental approach to preventing overweight and obesity. Key points covered are:

Introduction to an Environmental Approach

Overweight and obesity have traditionally been viewed as a problem of the individual. While individuals certainly play a role in their own weight management, recent research strongly suggests overweight and obesity are more than just individual problems. They result from the interaction of individuals with their environment.

The key role of environmental change is to make healthy choices the easy choices.

The environment in this context is not Mother Nature. Rather, it is the circumstances in which we live and eat. This table shows some dimensions of environment.

Environment Dimension	Description	Examples

Built/ Structural Environment	Physical environment Food choice Physical activity choices	Grocery store choices Workplace vending machine choices Walking/biking trails
Economic Environment	Can the community afford healthy choices? Money spent promoting healthy choices Money spent making healthy choices available	Can residents afford the fresh produce available in local stores? Does the town have money to make sidewalks safe to use?
Social Environment	Attitudes, perceptions, and values of the individuals in a community Media and advertising influences on individuals and their choices	Employees don't think they have time to take a walk on their lunch breaks It's tough to turn down doughnuts brought to the office by coworkers.
Policy Environment	Laws, regulations, and policies that impact eating and physical activity choices. (The policies may be part of the larger social environment or may reflect the "policies" in a home, workplace, or classroom.)	Worplace policies for healthy foods at meetings Lack of policy prohibiting snowmobiles on hiking trails.

We live in what has been called an obesogenic environment. This can be defined as the sum of influences (including our surroundings, opportunities, or conditions of life) which promote obesity in individuals and populations. The food environment in the United States

Although making healthy choices is ultimately the responsibility of the individual, in the context of an environment where healthy choices are extremely difficult to make, the entire burden of responsibility can not be solely individual. The larger food culture in the United States has much to do with the weight problems that are now so prevalent in our population. Changes in food use in the U.S. over the last 30 years are informative.

Factor in advertising from major manufacturers of fast food and convenience foods, and it is clear that we live in a food environment that makes healthy food choices more difficult.

If obesity is driven by the environment, then our focus should be environmental change, not individual will-power.

An environmental approach to obesity prevention takes all influences on obesity (individual, physical, economic, social and policy) into consideration when planning an intervention. It also specifically focuses on the changeable aspects of an environment versus the changeable aspects of an individual.

Environment-based interventions don't tell people how to eat; they make it easier for people to eat healthy.

An environmental approach is especially useful when it comes to physical activity and nutrition. Individuals will almost always make the easy choice or the choice that feels best. The easy choices are often convenience foods high in fat and sugar (which taste and feel good, and are often less expensive), and physical inactivity, because for most of us that feels good as well. An environment-based intervention shifts the options to make healthy choices easier and good-feeling.

The chart further explains the differences between individual and environmental approaches to obesity prevention.

Comparison of Approaches to Obesity Prevention
	Individual Approach	Environmental Approach

Focus	Changing the individual.	Changing the community environment.
Who/What Changes?	Individual behavior.	Structural, social, economio, or policy structures.
Who is Responsible?	Individuals working with health professionals.	Community leaders. policy makers, and health professionals working with community members.
Who is Affected?	People already interested in changing.	Everyone in the community.
Tools	Individual education.	Community development.
Side Effects	Stigmatizing and victim blaming.	Support individual approaches.

An Old Model for a New Problem

The epimiological triad is a useful model for framing obesity in an environmental perspective. The epidemiological triad is a traditional approach to looking at the origin and spread of infectious diseases. Recently it has also been applied to non-biological health problems like smoking and car accidents.

This model places obesity, which is usually thought of and treated as a biomedical problem, in an epidemic framework with a broader view. This presents more options for interventions.

Adapted from: Swinburn B and Egger G. Preventive strategies against weight gain and obesity. Obesity Reviews 2002:3:289-301.

In this model, the agent is chronic positive energy balance (overeating). The vectors are energy-dense foods, large portion sizes, labor saving devices, and physical inactivity. The model clarifies the synergy between the disease agents and vectors, the environment, and the affected individuals.

Part 3: Background
A Guide for Custom Community Intervention Planning

Key Points

Introduction to an Environmental Approach

Part 3: Background A Guide for Custom Community Intervention Planning

Key Points

Introduction to an Environmental Approach

Part 3: Background
A Guide for Custom Community Intervention Planning