Yan Bai POLICY SEMINAR Are healthy diets affordable? Using new data on retail prices and diet costs to guide agricultural and food policy Co-organized by IFPRI, Tufts University, the World Bank, and Food and Agriculture Organization (FAO) JUL 15, 2022 - 10:00 TO 11:30AM EDT

1. A deeper dive into the healthy diet basket and
global variation in diet costs and affordability
July 15, 2022
Dr. Yan Bai
Development Data Group, World Bank
School of Public Affairs, Zhejiang University
foodpricesfornutrition (worldbank.org)
Food Prices for Nutrition | DataBank (worldbank.org)

2. Meeting FBDGs with least-cost foods
almost always stays within
macronutrient distribution ranges,
near the lower bound for protein and
near the upper bound for carbs
Do least-cost diets following the HDB and other FBDGs also
provide balanced macronutrient intakes?
Source: Herforth, Bai and Masters, in progress
EAT-L
EAT-L
Energy
portion
Food Based Dietary Guidelines
Food Based Dietary Guidelines
Macronutrient balance of least-cost diets, by type of dietary guideline (red lines = upper and lower bounds)

3. All FBDGs meet requirements for nutrient adequacy, with exceptions
EAT-L
Do least-cost diets selected for the HDB, national FBDGs
or EAT-Lancet also achieve micronutrient adequacy?
Source: Herforth, Bai and Masters, in progress
Nutrient adequacy of least-cost diets, by type of dietary guideline (darker = more inadequate)

4. Do least-cost diets following the HDB and other national
FBDGs produce a similar level of GHG emissions as the EAT-
Lancet Diet does?
Least-cost diets produce a minimal level of GHG emissions, with exceptions
Source: Herforth, Bai and Masters, in progress
Kg
per
person
per
day
Food Based Dietary Guidelines

5. • “Energy sufficient diet” - Cost of Calorie Adequacy (CoCA)
• Minimum cost to meet energy requirements using the least expensive, available
starchy staple food in each country
• “Nutrient adequate diet” - Cost of Nutrient Adequacy (CoNA)
• Minimum cost to meet energy and nutrient requirements (23 macro and micro-
nutrients, with upper as well as lower bounds)
• “Healthy diet” - Cost of Healthy (Recommended) Diet (CoRD)
• Minimum cost to meet food-based dietary guidelines, based on food group
classifications; a behaviorally realistic way to meet nutrient needs and other
needs, including proportionality, norms, culture, and protection of health against
NCDs
We estimate the other two diet cost as reference indicators

6. Energy shares of
least-cost diets
Source: Bai, Y., E. Naumova and W.A. Masters (2020). Seasonality in diet costs reveals food system performance in East Africa. Science Advances, eabc2162.
Seasonality of diet costs and cost by food group in Tanzania, Malawi and Ethiopia
Assessing seasonality for diet costs may guide national
policy towards resilient food markets

7. Comparing diet costs to real wages reveals a gender gap in
affordability
Real wages (hours adjusted) have increased
for both men and women, more for men
Diets cost 50-60% of men’s daily wages, 80-
90% of women’s daily wages.
Men
Women
Men
Women
Source: : Raghunathan, Headey and Herforth 2021. Affordability of nutritious diets in rural India. Food Policy 99(2021): 101982.
Real wages and affordability of recommended diets in India

8. Source: Bai, Herforth and Masters, 2022. Global variation in the cost of a nutrient-adequate diet by population group. Lancet Planetary Health 6(1): 19-28.
Comparing the cost of nutrient adequacy by demographic
group reveals higher cost of foods needed by women and girls
Variation in least-cost diets by age, sex and reproductive status across 172 countries in 2017
Cost per day is highest for adolescents
or during lactation, due to high needs
for total energy and nutrients
Cost per calorie is highest for girls and women, due
to high nutrient needs per unit of dietary energy

9. Retail food price data are collected, but are not fully
published…
Availability of food item prices from national governments’
Consumer Price Index (CPI) data in 2019-2020
Availability of food item prices from international agencies’
Early Warning System (EWS) data in 2019-2020
Source: Bai, Y, et al. Retail consumer price data reveal gaps and opportunities to monitor food systems for nutrition. Food Policy 104 (2021): 102148.
It is not possible to calculate the cost of a healthy diet in most countries
using publicly available data; a coordinated reporting system is needed.

10. Current method uses food CPI or general CPI to estimate
diet costs starting from 2018, until the next round ICP data
become available
Average prices by food group, January 2019–June 2021.
(n=1,309 items from 86 countries, Jan. 2019 – Feb. 2021)
Source: Bai, Y. et al. (2022), Retail prices of nutritious food rose more in countries with higher COVID-19 case counts. Nature Food 3 (5), 325-330.
Food prices for different
food groups have
different changing rates
over time. During the
COVID-19 pandemic,
nutritious food has a
higher growth than
breads and cereals,
implying an
underestimate of diet
costs in 2020.