File:food-funnel.png

Summary

"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.

Limitations

This diagram doesn't currently include fish. Here's one way that fish could maybe be included in future versions of this diagram:

• The top part would be renamed from 'crops harvested' to 'production primary', and would include wild-caught fish.
• The 'animal feed' would include any human-edible calories fed to farmed fish.
• The 'animal products' produced would include the farmed fish.

To put things in perspective, seafood contributes about 12g protein/day/capita to the global food supply. [6]

Header & footer

The image's top & bottom text are redundant for most wiki pages, but needed in case someone shares the image.