A nutritious diet is essential for an active and healthy life but is unaffordable for about 3 billion people, almost 40% of the world's population, who have insufficient income to afford enough of even the least-cost foods needed for a healthy diet.

The unaffordability of nutritious foods prevents many people from consuming a healthy diet, but market prices for raw agricultural produce are not the only barrier to improved diet quality. To form an inclusive and sustainable food system for all, policies and programs should address other obstacles such as:

• the time burden and fuel use needed to cook safe and nutritious meals at home, especially in households with poor kitchen facilities and other constraints,
• high prices of healthy items that would be pre-cooked and prepared in ways that preserve and enhance nutritional value while reducing the time and fuel required for meal preparation, and
• rapidly growing availability of ultra-processed foods whose convenience, taste and brand reputation meet peoples' immediate needs, but are linked to diet-related disease later in life.

The data shown in this brief reveal that even just the raw ingredients for a basic plate are often unaffordable for the poorest, and the added cost of time and fuel can make such meals prohibitively expensive.

Results suggest two main avenues for policy action.

First, governments now can and should use the information on the least costly way to meet dietary standards to inform poverty lines and provide targeted assistance to ensure that citizens can acquire safe and nutritious items in sufficient quantities for an active and healthy life, using local-appropriate safety nets.

Second, food policies should recognize the hidden costs of meal preparation that often put healthier, more sustainable diets out of reach.

Overcoming the hidden barriers to preparation of healthy meals will require support for helpful forms of food processing such as cooking and canning beans, fish, tomatoes or other foods that preserve or even enhance nutritional values, while simultaneously taking action to limit potentially forms of ultra-processing such as excessive levels of added sugar, salt or trans fat and other factors associated with diet-related disease. Actions that support helpful forms of food processing while limiting harmful processing could help households improve diet quality, while also reducing the time burden, respiratory diseases and climate-change consequences of using wood or charcoal for cooking, as well as other inefficient and inequitable aspects of meal preparation. Taken together, food-based safety nets and improvements in the food environment can make healthy diets affordable for all people at all times, to help every country reach global development goals.