Meat-eating is seen as a sign of prosperity, and in China in 1962, the average person consumed just 4 kg of meat annually, now the figure is nearer 60 kg and increasing steadily. The UK has not been self-sufficient in food since the 18th century, and during WWI it was thought that the regular torpedo attacks on merchant ships from the colonies, as they then were, a part of the long since redundant British Empire, would starve the nation into surrender to Germany. Today we import 37% of our food, at a total cost of £22 billion, of which 68% comes from the European Union. London relies on imports for 80% of its food supply which makes me think that the Oil Dearth Era will be particularly harsh for such massive urban conurbations, which will not be readily devolved into self-sustaining communities.
Food prices have soared, and this applies to animal feed too, the cost of which must be passed-on to the consumer. It now costs £15 a month to feed a pig, or around double the cost of doing so a year ago. Wheat prices have also doubled, as we see in the rising cost of a loaf of bread. Fuel prices are on the "up" too. It is interesting that numerically, the price of a litre of diesel in pounds is the same as that in US dollars for a barrel of oil: i.e. £1.11 or $111 (more or less, but you get my point).
The average citizen of the United Kingdom eats 80 kg of meat per year, and the average American 124 kg. When I was a boy, meat was served up as a Sunday roast and then cold with "bubble and squeak, a strange British fare of the left-over potatoes and other vegetables, mainly cabbage, fried in "dripping", i.e. the fat which exudes from meat when it is roasted. Other than that I recall living on beans-on-toast, or cheese-on-toast. It did me no harm anyway! However, it is probably the reason why we British have such a poor reputation for the quality of our food, especially among the French, who are good cooks. However, I remember attending a conference on Zeolites in Southport, North West England, and meeting a nice Frenchman called Henri who said, "Ah it is not true that the British have bad food!" It was indeed a well-resourced conference and as I pointed-out, if the ingredients, meat and vegetables are of good quality, then the food here is fine.
Generally, I tend to cook at home and I think serve up something better than is normally presented in restaurants although these establishments too have improved vastly during the past 30 years. Pubs almost all do food these days and when I was in my late teens 30 years ago, they were exclusively drinking establishments, and food was a pork-pie or a bag of crisps - a scotch-egg or a pickled-onion if you were lucky! Interestingly, it requires 2 kg of grain to produce 1 kg of chicken but 7 kg for each kg of beef. I also recall when I was a kid that we all kept chickens! This was mainly for their eggs, and prior to battery-farming, chicken was an expensive (luxury) item, and indeed was often served-up at Christmas rather than turkey. Beef was relatively cheap, being home-produced, and lamb was (and still is) cheap as imported from New Zealand. Welsh lamb is far more expensive.
It might be argued that there is insufficient arable land on which to grow the grain to feed the animals that we kill to feed humans (which is never a pleasant notion). However, the facts are more complex. Specifically, in the United States, pesticides derived from hydrocarbons (i.e. oil) have increased in their use by 33 times. Practically all the food that we eat depends on oil or natural gas, the latter being converted into hydrogen which is combined with nitrogen to make ammonia via the Haber-Bosch process, and a substantial proportion of this is oxidised to nitric acid via the Ostwald process. The combination of the two provides ammonium nitrate, which is both a fertilizer and a high-explosive. The salient issue however is that 95% of all agriculture depends on hydrocarbons - oil and gas, either as a chemical feedstock or as a fuel.
Oil is a fulcrum of fertilizer-production, mechanised farming, transportation of food and the ubiquitous packaging that everybody loves to hate. Such modern farming methods have created an increase in grain production by 250% since 1950, and the cheapness of food held-back the rate of inflation and augured-in the post WWII consumer boom. In the global farmyard that is the modern world, prices have escalated at around 7.5% for bread, 15% for milk and other dairy products (e.g. cheese and eggs), while rice has increased its price by 60%. Food inflation runs at an average of 6.6% while the cost of a barrel of oil has risen by 70% (or 400% from its price of five years ago). We can only expect the cost of food and fuel to rise in accord with the raw price of oil.
Water-provision is another pressing matter. Less than 1% of the world's water is liquid freshwater - most water on earth comprises the oceans and is saline, while the bulk of freshwater is present as frozen ice, e.g. the massive shelves of Antarctica. Necessarily, the supply of freshwater is limited, and it takes anywhere from 100 to 1,000 times as much water to produce 1 kg of meat as 1 kg of grain. It has been pointed out that since 70% of all freshwater is used for farming, when buying food imported from elsewhere, in affect one is purchasing another country's water allocation. I hadn't thought of it that way, but it is true!
In a destructive synergy, rising oil prices, a real limit on how much land there is to grow food to feed either human or other animals, increasing demand for arable land to produce crops for biofuels, and the desertification of formerly arable regions in consequence to climate-change, the planet could not support a population of 6.7 billion meat-eaters. If we all turned vegetarian, this present number of us is probably sustainable for a while, but otherwise not. I recently estimated that in the absence of oil and gas based farming the Earth can probably support around 3 billion (Professor David Pimentel at Cornell University reckons closer to 2 billion), and there is a real threat of a die-off. It is interesting that by applying a Hubbert type population analysis, rather than the putative and often cited figure that by 2050 the world population will exceed 9 billion, I estimate that world population will peak at around 2025 at 7.3 billion, and then fall. By what means precisely this will happen is anybody's guess, but as is true of population analysis in general, of bacteria or humans, it is the underlying depletion of resources that determines precisely when and at what level this occurs.
"Only a radical change of diet can halt looming food crises," By Rosie Boycott. http://www.guardian.co.uk/commentisfree/2008/mar/28/food.ethicalliving/print