Fig. 1: Cost of healthy diets.

The cost of each recommended diet, defined as the cost of the least expensive food items to meet FBDG at a constant energy total of 2,330 kcal d⁻¹ in 2021 PPP dollars per person per day. The box plots illustrate the distribution of diet costs across countries. The central horizontal line within each box represents the median cost, while the upper and lower edges of the box indicate the IQR, covering the 25th to 75th percentiles of country-level diet costs. The whiskers extend to the minimum and maximum values within 1.5 times the IQR, with individual points beyond this range representing outliers. Diet cost estimates were derived for 172 countries where available to calculate the cost of meeting FBDG of Argentina (ARG), Benin (BEN), Malta (MLT), Pakistan (PAK), the United States (USA) and Viet Nam (VNM); from 171 countries of the HDB, Bangladesh (BGD), China (CHN), Ghana (GHA), India (IND), Indonesia (IDN), Jamaica (JAM), the Netherlands (NLD) and Zambia (ZMB); from 169 countries of Ethiopia (ETH), Oman (OMN); and 162 countries of the EAT-Lancet reference diet (EAT). The variation in the number of countries is due to differences in price data availability for the specific food groups required by each guideline. In some countries, price data for items in certain food groups may be unavailable, leading to slight differences in country coverage across the various diet cost calculations. The red line highlights the mean of diet costs across 16 national FBDG, which was $4.16 (median, $4.03) in 2021. This is higher than the mean and median of the HDB ($3.68) but lower than EAT (mean, $4.48; median, $4.27). The red dashed line represents the international extreme poverty line of $2.15 in 2017 PPP dollars.