The Rising Cost of a Healthy Diet – Changing Relative prices of Foods in High- Income and Emerging Economies

In 2014 our previous study ‘Future Diets’ (Keats and Wiggins 2014) described how across the world an increasing share of the population is overweight and obese, with the rate of increase particularly pronounced in developing countries. No nation, however, has stemmed the rising rates of people who are overweight and obese. Effective policies to combat obesity have yet to be proved, if only because no country has yet tested a sufficiently comprehensive set of policies. The causes of excess weight are multiple, including rising incomes, urbanisation and more sedentary occupations, the influence of media and advertising, and changing relative prices of different foods. This last element is the focus of this report. The report starts from two working hypotheses: a. When the relative prices of foods change, people will consume more of foods that have become relatively less expensive, and less of those that have become relatively more expensive. People on low incomes are expected to be more sensitive to prices than those on higher incomes; and, b. When consumption of foods with high calorie content per unit weight (energy-dense foods) increases at the expense of food that is less dense in energy, we may expect to see a significant increase in the prevalence of overweight and obese people.