The nutritional “double burden,” a price analysis

A terrible picture: on the one hand, 2 billion people who suffer from "moderate or severe" food insecurity, according to FAO terminology; on the other, 2 billion obese or overweight adults.[1]Children pay a heavy price for the global food disorder, either directly or through their parents. But that's not all. The dramatic human cost of the "double burden" of undernutrition and overnutrition is amplified by the increased risk of disease. One in five deaths is due to inadequate nutrition. In low-income countries, this is mainly due to a lack of calories, which leads to hunger, or to a deficiency in certain essential nutrients (proteins, vitamins, iron, etc.) linked to a lack of fruits and vegetables and animal products. In emerging or high-income countries, excess sugar, fat, and red meat are responsible for a significant increase in cardiovascular problems, diabetes, and cancer.

The causes of this situation are primarily economic. We are of course thinking of poverty, which prevents people from eating properly, in quantity and quality. But food prices are also a factor, either because of their high cost, which limits the quantities purchased, or because of the price hierarchy between foodstuffs, which penalizes relatively expensive foods that are essential for quality nutrition. The first point is well documented: the OECD has shown that food prices in sub-Saharan Africa are 30 to 40% higher than prices in the rest of the world, at a comparable level of GDP (gross domestic product) per capita.[2]A new study, conducted by researchers at IFPRI (International Food Policy Research Institute), sheds light on the second point.[3].

Using price data collected in surveys conducted in 176 countries under the auspices of the United Nations and the structure of food consumption in each of these countries, the researchers established the average value of a basket of 1,000 calories from nine basic starchy foods (cereals, tubers, and roots), rich in calories. They then calculated a relative caloric price (RCP) index by comparing the value of this basket with the cost of calories provided by different products or groups of food products. If, for example, eggs have an RCP of 5, this means that consumers in the country in question must pay on average 5 times more for a calorie of eggs than for a calorie of starchy foods.

The study shows that the relative price of high-quality, nutrient-rich foods decreases as countries develop. For example, in Niger, a calorie of egg costs 23.3 times more than a calorie of rice or corn; in the United States, the ratio is only 1.6. The situation is comparable, to varying degrees, for animal protein and fruits and vegetables. However, demand for different food products generally varies inversely with relative prices: the higher the RCP of a commodity, the less it is consumed.

Based on this observation, the researchers highlighted robust correlations between the relative prices of calories and the health status of populations. A high RCP for milk is linked to stunted growth in children, a major scourge in many poor countries. Low RCPs for sugar, soda, fats, and salty snacks are associated with a significant prevalence of obesity in adults, which mainly affects emerging or high-income countries. Thus, when a country's income increases, its inhabitants have access to healthier foods, but also to foods whose overconsumption has negative consequences.

The study's authors briefly discuss possible solutions. In less developed countries, the solution is to improve agricultural productivity to lower the price of nutrient-dense foods, or to increase their imports. In wealthier countries, reducing the demand for fats and sugar, which are very cheap (RCP less than 1), involves consumer education and information (labeling, nutrition education, etc.), as well as taxes on certain foods. Nothing revolutionary, then, but the task is immense because eating habits have deeply rooted cultural roots. All the more so, we might add, since for a small but growing proportion of households, eating is increasingly influenced by ethical and societal factors—climate change, biodiversity, animal welfare, proximity to producers, etc.—whose impact on relative prices remains to be assessed.

[1] FAO, IFAD, WHO, WFP and UNICEF, 2019. The State of Food Security and Nutrition in the World 2019. Guarding against economic slowdowns and downturns, Rome, FAO.

[2] Food prices must fall in Africa. How can we do this?, Thomas Allen, Secretariat of the Sahel and West Africa Club, FARM blog, February 5, 2018.

[3] Derek D. Headey and Harold H. Alderman, 2019. The Relative Caloric Prices of Healthy and Unhealthy Foods Differ Systematically across Income Levels and Continents, The Journal of Nutrition, July 23, 2019.