Getting Obesity Under Control: The Importance of a Systems Approach

New research focuses on the cause and spread of the obesity epidemic and just how difficult it will be to coordinate efforts to get it under control. The epidemic not only causes serious health problems but is also driving up medical costs dramatically—by some estimates, 100 percent higher. Senior Fellow Ross Hammond examines the issues around obesity, arguing that the best way to coordinate effective prevention policies is to use a systems approach to model and coordinate the policy side, the scientific side and different methodologies. Hammond’s recent work features extensively in a major new National Academy of Sciences/Institute of Medicine (IOM) report on obesity, as well as a collaboration between the Centers for Disease Control and HBO for the event, “The Weight of the Nation.”

“The obesity epidemic has really become a very pressing problem in the United States and, actually, worldwide. Here in the U.S. two in three adults are now overweight, and one in three are obese; and among children and adolescents one in three are overweight. So these are very large numbers and there are some serious public health consequences of this. Being overweight and obese puts you at much higher risk for things like several cancers, diabetes, cardiovascular disease, and also things like asthma and arthritis.

So in addition to these public health consequences there are some real economic costs associated with [being] overweight and obese. In particular, medical spending is much higher among the overweight and obese. Some estimates say as much as one hundred percent higher. So that adds up to quite a bit in medical spending, and (again) by most estimates at least twenty-one percent of U.S. medical spending is driven by obesity already. That number could easily go up, so that is some of the economic side of it.”

Preventing obesity is the best way to stop the epidemic (1:11)

“The main thing to think about it how important prevention is with obesity, in particular, because once obesity exists there are some very powerful physiological processes and behavior patterns that are very entrenched, and it is quite difficult to reverse. This is the reason why the majority of overweight and obese children go on to be overweight and obese adults. Prevention, particularly early prevention, is really important. I think that is the fundamental focus.

Unfortunately, prevention is also hard. Obesity is a very complex syndrome that is driven by many, many different factors. In one sense it is extremely simple because it is about energy balance – energy in and energy out. If you take more energy in than you have energy out you will gain weight. It is as simple as that. On the other hand it is quite complex because the drivers of what you eat, how much physical activity you get, and what your resting metabolic rate are quite complicated and involve biology, physiology, and genetics; but [it also involves] advertising, marketing, and social norms, our agricultural system of production and distribution, the physical environment around us where we live, and how our world is structured. All of those things work together to produce different outcomes. That linkage between these different factors is less well-understood and is actually very important for trying to do policy in this space.”

A systems approach to obesity needed (2:42)

“I think there is a growing consensus that what we need to do in order to do a better job of preventing obesity is to coordinate activity across different sectors and different levels of scale, or to take what is called a “systems approach.” A systems approach means that you try to coordinate what is going on in education in schools, what is going on in transportation in urban planning, and what is going on in agriculture because all of these things are linked together, and they all drive health outcomes (for obesity in particular). They tend to be addressed from a policy perspective and from a science perspective separately. Really connecting what we are doing in a coordinated and cohesive way is extremely important for making progress on this issue.

Some of the modeling work that we do at the Center on Social Dynamics and Policy here at Brookings is helping to explore these complex linkages, both across sectors (so what is happening in the private and public sectors) but also what is happening at the different levels at the federal, state and household levels. Finally, these connections between the biology, physiology (what is happening inside of people and in their brains as they eat food and observe advertising), and what is happening around them in their physical and social environment – all of these are connected. Models can help us to understand how they work together, and how to design policies that work together to address it more holistically.”

There are three systemic barriers to preventing obesity (4:11)

“There are definitely barriers in the way; there are at least three sets. One set of barriers is institutional. On the policy side we have different departments of government for public health and for the things that actually drive public health, as well, such as education, transportation and agriculture. They are not necessarily used to working together, but they really need to to address this problem. The second set of hurdles in on the scientific side. We have different fields of science – genetics, nutrition, business – and they do not usually talk to each other or work together, either. They also need to to help us understand this problem. The third set of challenges is really methodological. We do not have tools that are good at this amount of complexity, and at helping us to manage it and design effective policies. These new tools that have arisen to address this challenge is what we really specialize in here at the [Center on Social Dynamics and Policy]. We are helping the federal government and the scientific community to apply [expertise] to the obesity epidemic.”

Two out of three overweight people live in the developing world (5:17)

“In the international context the picture looks (in some ways) very different from the United States context. In fact, a lot of obesity is occurring in the developing world. Two in three overweight people in the world are in developing countries, not in the developed world. This is a surprising statistic. In the developing world everything is changing very rapidly. Their systems of growing, producing and distributing food are changing very rapidly as they develop. Their social norms and tastes are developing very rapidly.

What you find in many developing countries is, at the same time, there is a lingering epidemic of widespread malnutrition and a new obesity epidemic which is getting quite bad. They coexist, sometimes even in the same village, or even in the same household. That is a bit of a puzzle, but I think it is because both things are driven by the same fundamental underlying systems that effect nutrition. Malnutrition and over-nutrition (which is what leads to obesity) are really part of the same problem. One of the challenges for developing countries will be to solve their malnutrition crisis without creating an obesity epidemic. That is very challenging to do and it involves coordination between the agriculture sector, and our understandings of environment and health, are how the three are all working together to produce one or the other obese effects, or sometimes both at the same time.