Using national price data for 657 standardized food products in 176 countries collected under The International Comparison Program (ICP), the researchers develop a novel measure of how costly it is to diversify diets away from traditional calorie-dense staple foods such as bread, corn or rice.
The study shows that higher caloric prices of a food predict lower consumption of that food and explores how those price differences might explain international differences in child stunting and adult obesity.
“Our research shows that most healthy foods are substantially more expensive in poorer countries. But while healthier foods become cheaper over the course of development, so too do unhealthy processed foods, like soft drinks,” Derek Headey, senior research fellow and study co-author, IFPRI said in a statement.
“Prior to this study, we already knew that the poorest children in the world were not consuming enough of the really nutrient-dense foods that promote healthy growth and brain development.
“But now we have a better idea why: poor people also live in poor food systems. That combination of low incomes and high prices means they’re simply not going to buy enough and eat enough of these nutrient-dense foods,” Headey said.
The study finds marked variations in the affordability of both healthy and unhealthy foods across different regions of the world, and at differing levels of development.
In the world’s poorest countries, healthy foods were often extremely expensive, especially nutrient-dense animal sourced foods, which are widely known to be effective in reducing stunting, the study states.
Eggs and fresh milk, for example, are often 10 times as expensive as starchy staples. Another ultra-healthy food for kids – specialized infant cereals fortified with a wide range of extra nutrients – are sometimes 30 times as expensive as the nutrient-sparse traditional cereals more commonly fed to infants.
While poor child feeding practices are often attributed to limited nutritional knowledge in low income settings, the authors found that the high prices of nutrient-dense foods offered an alternative explanation of their low consumption. Even more strikingly, they find that higher prices of milk, eggs and fortified infant cereals predict higher rates of stunting.
“The link between milk prices and stunting is especially strong which is entirely consistent with a whole body of evidence on the strong linkages between dairy consumption and child growth,” said Harold Alderman, co-authored, IFPRI.
“Public health agencies in upper income countries have been concerned with the high consumption of sugar-rich foods for some time but our study shows that these products often become very affordable in middle income countries, and sometimes even in relatively poor countries where obesity rates are really on the rise,” Alderman said.
Josephine Okojie
