Dr. Adam Drewnowski, Professor of Epidemiology at the University of Washington and the Director of the Center for Public Health Nutrition at the School of Public Health, has dedicated his career to research on obesity and social disparities in diet and health. Food Tank recently had the chance to speak with him about his research into food price as a link between climate change and obesity. His 2013 article, “Climate Change and the Role of Food Price in Determining Obesity Risk,” concludes that climate change will make low-nutrient foods more affordable and thus increase their consumption and increase obesity rates. When we spoke with Dr. Drewnowski, he elaborated on this relationship, discussed his career, and talked with us about his development of the Nutrient Rich Foods Index and the Affordable Nutrition Index.
Food Tank (FT): Before we discuss food price as a link between climate change and obesity, could you elaborate on your past experiences and research? What inspired you to pursue obesity research?
Dr. Adam Drewnowski (AD): Thirty years ago, I started out at Rockefeller University in a lab dealing with fat cells and cell metabolism. The hospital there was a big center of the clinical and metabolic aspects of obesity. I performed research on taste function and food preferences, specifically looking at the role of fat, sugar, and salt on food preferences. This prompted me to look at the low cost of sugar and fat later in my career—I knew it couldn’t be a coincidence that we have created the food industry to give us foods we like and give them to us cheap.
FT: Could you expound upon your development of the Nutrient Foods Index and the Affordable Nutrition Index?
AD: The Nutrient Rich Foods Index rates individual foods based on their overall nutritional value and the Affordable Nutrition Index helps consumers identify affordable, healthy foods.
With the Nutrient Rich Foods Index, we wanted to distinguish between empty calories and nutrient-rich calories. It is measured by examining nutrients per calorie. Foods that score highly are those that are rich in nutrients and low in calories. The Affordable Nutrition Index came about because nutrient-rich foods are expensive—we wanted to evaluate what foods give a big nutritional load for a low cost. The Index measures nutrients per penny, with foods like beans, eggs, milk, yogurt, potatoes, lentils, and carrots scoring best.
FT: The main conclusion of your 2013 article, “Climate Change and the Role of Food Price in Determining Obesity Risk,” is that a rise in food prices because of climate change will increase obesity rates. Can you describe this relationship?
AD: With climate change, we will likely become more reliant on cheap, staple crops because they are resilient and inexpensive. These crops, like rice, soy, corn, and sugar, may feed calories, but they don’t necessarily provide nutrients. An increased reliance on these crops could increase obesity because obesity is mostly due to cheap, empty calories with minimum nutritional value. What’s more, climate change puts constraints on vegetables, fruits, livestock, and dairy, making it more difficult to obtain nutrient-rich foods.
FT: How will this disproportionately affect impoverished communities and what steps can policymakers take to mitigate this disproportionate influence?
AD: We already see that lower income groups in this country consume cheap, nutrient-poor diets. This will just become aggravated over time. It is worse in low and middle-income countries with limited resources. We need to start paying more attention to nutrient-dense crops that are also inexpensive, like beans and lentils. We must identify which affordable diets give the best nutrition for the lowest environmental costs. There is a lot of room for policy on this. Nutritionists and the individuals who develop the United States dietary guidelines should pay attention to the environmental consequences of what they recommend.
FT: Will a solution to this problem require collaboration between the health and environmental sectors? What do you see as the most important steps needed to address this problem?
AD: Absolutely. And a partnership is already in the works. We collaborate with people doing climate change work. There are two main approaches we can take. The first is based on the Giessen Declaration, which says that nutrition scientists should embrace sociology, anthropology, economics, etc. to take a broader global picture of health systems. In recent years, we have seen nutrition scientists starting to do this.
The second approach is to join agriculture with nutrition. Agriculture is all about producing more crops, but some of those crops are not necessarily related to nutritional needs. We need to produce calories and nutrients, not just calories.
FT: Are there any organizations or individuals working in this space with whom you are particularly impressed?
AD: I am a scientific advisor to the Carasso Foundation, which is a French foundation doing really great work in this space. They focus on feeding the world a healthy diet, while protecting the planet’s resources, by encouraging and rewarding research into this.
The Barilla Center for Food & Nutrition is also great. They are a think tank that produces research to help people make conscious choices about nutrition, health, and sustainability.
Finally, the Wellcome Trust. They’re a global charity foundation that supports people exploring ideas in science, population health, medical innovation, the humanities and social sciences, and public engagement.
FT: How do we raise general awareness about this important relationship between climate change and obesity?
AD: This is a great point. When we think of climate change, we don’t immediately associate it with chronic disease mediated through a change in diet. We need to pay attention to the impact climate change has on the foods we eat. Focusing on these indirect, but very important, effects could take us in promising new directions.
FT: What other mechanisms between climate and change and obesity have you or your colleagues studied?
AD: Another idea we are looking at is the ongoing phenomenon of urbanization. People are moving into cities worldwide, and obesity is now hitting the poor in the big megacities; it is not hitting the rich anymore. Living in the city restricts direct access to food production, forcing people to eat processed, packaged, and often unhealthy foods.