File:food-funnel.png

Summary

The world produces more than double the amount of food crops needed to feed everyone. But after all the waste, losses, and animal agriculture, there isn't enough food left to go around; people still go hungry.

Overview

"The world produces enough food, but where does it all go?"

This diagram shows the main inefficiencies of the global food supply.

It visualizes the relative proportion of:

• food crops harvested from farms (a.k.a. the production primary)
• food burned as biofuel
• food fed to animals
• food produced by animals
• food loss
• food waste
• food actually eaten

For animal feed, the diagram does not count grasses, crop residues, or anything else inedible to humans. The diagram strictly shows the usage of human-edible foodstuffs.

Methodology

The thickness of each branch in the diagram, is proportional to the human-edible calories of food involved.

All the per-capita numbers below are calculated as (total food) divided by (world population).

Food Crops Harvested: 5454 kalories/day/capita

• calculated by Code:food1.sql
  • SQL code: SELECT SUM(production_kalories_per_day)/7.9e9 FROM main WHERE region_name="World";

MINUS: Biofuels: 491 kalories/day/capita

• calculated as 9% of Food Crops Harvested. The '9%' comes from [1] and refers to calories.

MINUS: Animal feed: 1964 kalories/day/capita

• calculated as 36% of Food Crops Harvested. The '36%' comes from [2] and refers to calories.

PLUS: Animal products: 518 kalories/day/capita

• calculated from Code:food2.sql
  • SQL code: SELECT SUM(kalories_per_day_per_capita) FROM summary;

Now we're at: 3518 kalories/day/capita

• Call this the "Supply".

MINUS: Food loss: 493 kalories/day/capita

• calculated as 14% of Supply. The '14%' comes from [3] which doesn't specify protein or calories or mass or volume, we just have to assume.

MINUS: Food waste: 598 kalories/day/capita

• calculated as 17% of Supply. The '17%' comes from [4] which doesn't specify protein or calories or mass or volume, we just have to assume.
• More details derived from the same source:
  • Household food waste - 387 kalories/day/capita (calculated as 11% of Supply)
  • Food service waste - 176 kalories/day/capita (calculated as 5% of Supply)
  • Retail waste - 70 kalories/day/capita (calculated as 2% of Supply) (percentages don't add up due to rounding errors; this causes kalories to not add up either)

Food Actually Eaten - 2427 kalories/day/capita

• Net result.
  • However, this is a global average. 10% of the world is still undernourished, living on less than 1800 kalories/day.

Finally, to estimate the food that would be needed to end global hunger, we add 2400 kalories/day (...)( which might be an overestimate, since undernourished people still eat some calories already ) for every undernourished person. There are currently 829 million people undernourished (10% of global population), according to [5]. Divide by the world population, for the sake of comparing in the same per-capita units used above.
252 kalories/day/capita

The diagram shape was generated by Code:make-flow-diagram1.html, and the resulting image was edited to add annotations and coloring.

Notes

Geography

This diagram is a world overview.

It would be worthwhile to also create local versions of this diagram, by country. Note that the diagrams would be more complex because of imports & exports at every stage.

If the diagram was done for rich countries such as the USA, the 'food waste' and 'animal feed' sections would be proportionally a lot bigger.