However, these increased food supplies were achieved by using finite supplies of oil and gas to greatly boost the yield per acre. Fossil fuelled machines increased productivity while at the same time releasing the 30% or so of land that was previously needed to feed the millions of horses used in farming, transport and the army. Nitrogen fertiliser made from natural gas now gives us about 40% of our grain yield on average,  and pesticides made from oil keep our crops free from weeds, fungal diseases and insect pests.
So the question is: can we continue to increase food production to keep pace with population growth which will add about 1.5 billion people in the next 20 years? Unless we make really big changes to the way we live and farm, the answer must be no.
Production of food per capita may have already peaked, but the problem has been hidden by drawing down on world reserve grain stocks. This is the amount of grain left when a new harvest begins in the northern hemisphere and act as an insurance against a bad harvest. Just a few years ago this stood at about 120 days supply but has now dwindled to about 50 days which is considered dangerous.
If stocks fall any more, it could lead to panic buying by countries, companies and ordinary consumers. We could be very close to that as grain prices have risen from £70/ton in September 06 to £100/ton now. Futures markets are showing further increases for next year.
The difference between feeding 2.5 billion in 1945 and 6.6 billion now is mainly down to a finite resource that must decline at some time and is increasingly owned by unreliable and unfriendly countries. Disruption of oil and gas supplies could happen at any time causing a big reduction in food supplies.
In addition we have other huge threats to food production including climate change, collapse of fisheries, loss of land to development and desertification, and competition for cropland for biofuel production.
At the same time, people in developing countries are including more meat in their diets, so that more land is needed per person when we will have less. All of these problems are discussed in more detail in separate posts on this website listed under various categories or for the complete picture, buy my e-book, Famine in the West.
