Research shows high prices of nutritious foods contribute to malnutrition worldwide

Poor diets are now the leading risk factor for the global burden of disease, accounting for one-fifth of all deaths worldwide. Although the causes of poor diets are complex, new research concludes that the price of more nutritious foods is an important factor.

A new study by researchers at the International Food Policy Research Institute (IFPRI) is the first to document that the affordability of healthy and unhealthy foods varies significantly and systematically around the world. . The study also suggests that these relative price differences help explain international differences in eating habits, stunting among children, and the prevalence of overweight among adults.

Previous research has only examined relative price differences in specific countries, mainly in the context of the relatively low cost of processed foods high in calories as a risk factor for obesity in high and middle income countries. But so far, no study has examined the structure of global price differences, nor how these price structures could contribute to the outcomes of undernutrition and nutrition. 39; obesity.

Our research shows that most healthy foods are significantly more expensive in the poorest countries. But if healthy foods become cheaper during development, the same goes for unhealthy processed foods like soft drinks. "

Co-author of the study, Derek Headey, Senior Researcher, International Food Policy Research Institute (IFPRI)

The study, "Relative Caloric Prices of Healthy and Unhealthy Foods Systematically Differ According to Income Levels and Continents", co-authored by Headey and Harold Alderman of IFPRI, was published in The nutrition journal. Using national price data for 657 standardized food commodities in 176 countries, collected as part of the International Comparison Program (ICP), the authors develop a new measure of the cost of dietary diversification of rich traditional staple foods in calories, such as bread, corn or vegetables. rice. The study shows that higher caloric prices for a food predict lower consumption of this food and explain how these price differences could explain international differences in stunting in children and children. obesity in adults.

The study found marked variations in the affordability of healthy and unhealthy foods in different regions of the world and at different levels of development. In the poorest countries of the world, healthy foods were often extremely expensive, especially nutrient-rich animal foods, whose effectiveness is recognized for their effectiveness in reducing stunting. Eggs and fresh milk, for example, are often 10 times more expensive than starchy foods. Another ultra-healthy food for children – specialty infant cereals enriched with a wide range of additional nutrients – is sometimes 30 times more expensive than traditional sparse-nutrient cereals, most commonly fed at home. infants.

"Prior to this study, we already knew that the world's poorest children were not consuming enough nutrient-rich foods that promote healthy growth and brain development," Headey said. "But we now have a better idea of ​​the reason: the poor also live in poor food systems.This combination of low incomes and high prices means that they just will not buy enough and eat enough of these foods. rich in nutrients. "

While poor infant feeding practices are often attributed to limited nutritional knowledge in low-income countries, the authors found that high prices of nutrient-rich foods provided an alternative explanation for their low consumption. . Even more striking, they find that higher prices for enriched milk, eggs, and infant cereals predict higher stunting rates. "The link between milk prices and stunting is particularly strong," said Alderman, "which is entirely consistent with a whole body of evidence about the close links between dairy consumption and growth. children ".

Although the study found that economic development tends to make healthy foods more affordable, this process also tends to make unhealthy foods less expensive. Sugar-rich soft drinks are relatively expensive in many low-income countries, but have become inexpensive and widely consumed in middle- and high-income countries.

Headey and Alderman find that lower prices for non-alcoholic beverages and high-sugar snacks predict a significant increase in the prevalence of overweight among adults. "Public health agencies in high-income countries are concerned about the high consumption of high-sugar foods for some time," said Alderman, "but our study shows that these products often become very affordable in middle-income countries, and sometimes even in poor countries where obesity rates are really on the rise. "

The researchers noted that policymakers have several tools to make nutrient-rich foods relatively more affordable, including nutrition-sensitive farm investments that could make healthy foods cheaper, and tax and nutrition efforts. regulation – such as food labeling – to reduce the consumption of unhealthy foods. .

"These results raise an important agenda for future research: to understand why food prices vary from one country to another, and sometimes within a country, and which is the best way to change food prices in ways that improve diets and nutrition in rich and poor countries, "Headey said.