Factory farming wastes resources, requiring vast inputs but giving relatively little food energy in return.

Animal farming converts plant products into meat, milk and eggs. More traditional farming methods can be relatively efficient, converting grass and other waste products into useful food. But the 'fast-growth, high-yield' factory-farming model is far less efficient, using huge amounts of resources, such as water, grain and oil, but providing relatively little energy in return.

Protein factories in reverse

Although factory-farmed animals are given a lot of feed, much is wasted - animals cannot convert everything they eat into meat because the energy is used for other activities, such as moving around and keeping warm. In 2000, it was calculated that for every kilo of meat produced, many more kilos of animal feed are required¹.

On average, it takes around 6kg of plant protein to produce just 1kg of animal protein.

The American Journal of Clinical Nutrition (AJCN) (2003)²

High resource use

Because so much feed is used for factory farming, a large amount of other resources are needed to grow it. One of these is land, much more of which is needed to produce meat or dairy products than to produce vegetables, cereals or fruit³. And then there's water, which is often used to irrigate the crops, particularly when they are grown in countries which have lower levels of rainfall. According to the WWF⁴, livestock production accounts for around 23% of all water used in agriculture - equivalent to more than 1,150 liters per person per day. A lot of energy is needed too, in particular for the manufacture of synthetic fertiliser and pesticide to grow feed crops⁵. Furthermore, these pesticides and fertilisers require large volumes of valuable resources such as nitrogen and phosphorus. Many of these resources could be put to better use, helping us to grow enough crops for the current world population, for example.

It takes over 15,000 liters of water to produce an average kilo of beef. This compares with around 1,200 liters for a kg of maize and 1800 for a kilo of wheat.

United Nations Educational, Scientific and Cultural Organization (UNESCO) (2010)⁶

'Peak everything'

The word 'peak' is used in relation to a range of non-renewable resources such as oil and phosphorus⁷, both of which are used heavily in factory farming. Essentially it means the time when the availability of a resource reaches a peak, and supplies start to dwindle. While views vary on when these materials will run out, the simple reality is that there will come a time in the future when we do not have access to some of the materials that we have come to depend on for factory-farmed food. And because these materials are now found in limited countries, there are obvious geopolitical risks for countries that are net importers⁸.

In the US, chemical-intensive farming uses the equivalent of 1 barrel of oil in energy to produce 1 ton of maize - a major component of animal feed.

World Bank (2008)⁹

But don't just take our word for it

It is clear that feed production consumes large amounts of critically important water resources and competes with other usages and users.

United Nations Food and Agriculture Organization (UNFAO) (2006)¹⁰

The production of meat from animals fed on irrigated crops has a direct impact on water resources, much more so than if the meat is derived from grazing animals and animals fed on [crop] residues.

Stockholm International Water Institute (SIWI) (2008)¹¹

So what?

Factory farming wastes resources. By taking action against factory farming, we are not just creating a food and farming revolution; we are also saving vital resources, which can be put to better use elsewhere.

Our sources

1. Smil (2000), Feeding the World: A Challenge for the Twenty-first Century, MIT Press
2. AJCN (2003), Sustainability of Meat-based and Plant-based Diets and the Environment
3. AJCN (2003), Sustainability of Meat-based and Plant-based Diets and the Environment
4. WWF (2008), Living Planet Report 2008
5. Pimentel (2006), Impacts of Organic Farming on the Efficiency of Energy Use in Agriculture
6. UNESCO (2010), The Green, Blue and Grey Water Footprint of Farm Animals and Animal Products
7. Nature (2009), The Disappearing Nutrient
8. SEI (2004), The Precarious Geopolitics of Phosphorous
9. World Bank (2008), Agriculture for Development
10. UNFAO (2006), Livestock's Long Shadow
11. SIWI (2008), Saving Water: From Field to Fork