Berners-Lee, Watson and Hewitt 2018
Berners-Lee, M., Kennelly, C., Watson, R., & Hewitt, C. N. (2018). Current global food production is sufficient to meet human nutritional needs in 2050 provided there is radical societal adaptation. Elem Sci Anth, 6, 52.
Feeding crops to animals actually decreases the amount of calories, protein, iron and zinc available to humanity. Malnutrition
- We present a quantitative analysis of global and regional food supply to reveal the flows of calories, protein and the micro-nutrients vitamin A, iron and zinc, from production through to human consumption and other end points.
- We quantify the extent to which reductions in the amount of human-edible crops fed to animals and, less importantly, reductions in waste, could increase food supply.
- The current production of crops is sufficient to provide enough food for the projected global population of 9.7 billion in 2050, although very significant changes to the socio-economic conditions of many (ensuring access to the global food supply) and radical changes to the dietary choices of most (replacing most meat and dairy with plant-based alternatives, and greater acceptance of human-edible crops currently fed to animals, especially maize, as directly-consumed human food) would be required.
- Strange they would say this as the paper suggests that because most animals are fed human inedible plants, animal product consumption worldwide would be cut in half
- Under all scenarios, the scope for biofuel production is limited.
- Our analysis finds no nutritional case for feeding human-edible crops to animals, which reduces calorie and protein supplies.
- If society continues on a ‘business-as-usual’ dietary trajectory, a 119% increase in edible crops grown will be required by 2050.
Even if we saw 0 increase in agricultural efficiency between 2013 and 2050, if we stopped feeding crops to animals we could feed everyone in 2050.
If we don't curb meat and dairy consumption, we'll need to increase crops by 119%
- in 2013 we produced 5935 kcal per person per day.
- Of the 5935 kcal/p/d directly edible by humans, 338 kcal/p/d are left in the ground or lost during harvest and 332 kcal/p/d are lost post-harvest.
- Of the remaining 5265 kcal/p/d, 30% are exported internationally but only 29% are received as imports (the difference being a trading loss of 73 kcal/p/d).
- Globally, 808 kcal/p/d are directed to ‘non-food uses’, mainly biofuels, particularly liquid hydrocarbons (Serrano-Ruiz et al., 2012).
- Other uses include cosmetics, pharmaceuticals, paints etc.
- A further 126 kcal/p/d are invested for re-planting.
- Of the remaining 4260 kcal/p/d directly edible by humans, 1738 kcal/p/d (41%) are fed to farmed animals.
Vitamin A
Industrialised Asia is the only region with a significant net surplus in human consumption above the ARI of naturally produced vitamin A. Every other region of the world has a deficit in vitamin A consumption, unless this is mitigated by fortification and/or supplements.
Animals provide more vitamin A than they are fed in human-edible crops, with a 214% return, and contribute 37% of the vitamin A eaten. In the absence of fortification and supplements, therefore, the global consumption of vitamin A would be 11% less than that required to meet human needs
Iron and Zinc
Every region in the world produces enough iron and Zinc. However, because of variations in the bioavailability of iron in different diets, variations in individual requirements (especially for adult females) and the prevalence of unbalanced diets, this does not mean that all individuals consume sufficient iron, and in fact iron deficiency is a significant global health problem
### Zinc
animals return 21% of the zinc they eat in human-edible crops
iron
human edible crops provide almost 6 times our iron needs, (63mg/p/d produced vs 11mg/p/d required). 41mg is fed to animals which delivers only 3mg back, a return of just 7%. While this "animal iron" is much more bioavailable, that is dwarfed by fact that 93% of the iron animals eat is lost. Critics are right when they point out that iron from plants is not highly bioavailable: its not bioavailable to the animals we eat either!
Even after allowing for a conservatively high factor of four difference between the bioavailability of haem and non-haem iron (Institute of Medicine Panel on Micronutrient, 2000), vegetable food remains the dominant source of absorbed iron in the global average human diet.
Regional differences
- all regions actually produce enough calories
- All regions consume enough protein
- Industrialised Asia is the only region with a significant net surplus in human consumption above the ARI of naturally produced vitamin A. Every other region of the world has a deficit in vitamin A consumption, unless this is mitigated by fortification and/or supplements.