One of the basic principles of nutrition is the meeting nutrient requirements, meeting your bodies demand for nutrients that it cannot generate itself or is not very good at making. By selecting something to eat which is similar to our own nutrient composition, this demand can be met very efficiently. Putting it very bluntly, humans contain a lot of muscle hence eating the muscle (meat) of other animals meets this requirement. Perhaps more appropriately, most nutritionists would tend to describe meat as a valuable source of high biological value protein, as well as minerals (iron, zinc, selenium and phosphorus) and vitamins (vitamin B12 and other B complex vitamins). Fundamentally meat can have a positive role in meeting our nutritional requirements. It is basically good for you, but like anything in our diet more is not necessarily better. The perception of the value of meat as part of the diet is often dependent where in the world this is being considered. In Developed industrial countries it is often thought as a significant factor contributing to diet-related non-communicable diseases. However, in Developing countries it is considered as means or reducing malnutrition and a component that many aspire to have in their diet.
How much meat do we eat? The global imbalance.
The short answer is we eat a lot of meat, but, as might be expected, specific countries eat more than others. Developed Industrial countries eat around 100kg per person in a year, whilst in Developing countries this is 32kg. Not all countries eat the same type of meat. The biggest consumer of beef is Uruguay and Argentina eat the most beef around 45kg per person. For pork, the EU and China consume the most at around 32kg per person. Whilst for poultry the largest consumer, by some way, is Israel at 58kg per person per year. So globally there is a large difference in consumption, with countries like USA and Australia consuming lots of meat within all these livestock species, having total consumptions of around 107kg per person. In contrast places like Ghana (Africa) consume a total of 7kg per person in year and this virtually all being poultry.
Consumption of meat is an aspiration for individuals in developing countries. It increases as countries become more urbanised, with the movement of populations move from the countryside into towns to do jobs which are associated with industrialisation. This move is often associated with an increase in personal wealth. An indication of the impact of this on meat consumption can be seen in the figures for East Asia (which includes China) where from 1995 to 2015 there has been an 58% increase in meat consumption per person. This is compared to a 11% increase in the Developed Industrial countries over the same period. The meat sector which has seen the biggest increase is poultry where global consumption has increased by 48% from 1995 to 2015. The global demand for meat is going to rise with these trends continuing, developing countries having the greatest increase. It is estimated that consumption of meat will nearly double by 2050.
What does it take to produce it?
To meet this projected demand for meat more animals will have to be grown. They have to be fed. Not all animals are equally efficient at growing. Sheep and cattle are relatively inefficient requiring an average of around 10kg of feed to give 1kg body weight. For pigs this figure is around 3kg, whilst chickens used for meat consumption (broilers) are the most efficient at using food, requiring 1.7kg for every 1 kg body weight. Chickens also grow quickly, it takes 42 days for them to achieve a weight of around 2.5kg. A remarkable growth rate. It is no wonder why there has been a large expansion in poultry production across the world.
Ultimately an inefficient animal will excrete more, which causes environmental issues, but also costs more to raise, which is translated to the cost of the meat on the supermarket shelf. To produce an animal for meat 70% of the costs of this process are associated with buying the feed. Chickens and pigs require less feed to grow than sheep and cattle. However, to achieve these efficient growth rates they have to be fed specific feeds. Their feed is made up of crops that are also used to feed humans, such as soya beans, wheat and barley. Soya beans are an essential component of their feed, as it contains relatively high quantities of protein, which is required for animal growth. Around 80% of the world production of Soya is used to feed livestock, and only a certain number of countries in the world can produce Soya beans. This crop is a limited resource. The questions which the meat producing industry is increasingly asking itself is how can it find the ingredients for animal feed to support the increasing demand for meat, particularly in developing countries, where meat is regarded as food that can reduce malnutrition? How does the world secure the production of this food, and many others, too supply a growing world population?
Let them eat grass?
Compared to chickens and poultry cattle and sheep are relatively inefficient in converting feed into meat. This efficiency is worse if these animals are fed grass – most cattle are fed significant quantities of cereals in addition to grass, to enhance their growth. On grass, it can take up to 20kg of feed to get 1 kg of body weight. So, the idyllic image of cattle grazing in fields does not equate to an efficient production system. However, this system of feeding livestock does not compete with humans, people don’t eat grass (they can, but not if they want to be healthy!).
An alternative way to consider the efficiency of producing meat is to think of how much food is being eaten by the animal which could be eaten by a human. This has been elegantly calculated by Professor Maggie Gill and her colleagues (Aberdeen University) by considering the protein in animals’ feed. For example, for every 1kg of protein in chicken meat 3kgs of protein in the feed is required, of which 2.1kg could be eaten by a human. In comparison, for cattle raised on the hills of Scotland eating mainly grass, for every 1kg of beef protein 26kg of protein is required in the feed, but less than 1 kg is protein that a human could eat.
Is eating beef and lamb the answer?
Cattle and sheep eat food that humans can’t, so is the production of these species for meat more sustainable? If cattle sheep eat grass rather than cereals they take longer to grow, they occupy more land and they produce more methane. Methane is a gas generated in cattle and sheep digestive system which they release to the environment (by belching). It is a greenhouse gas which is worse the carbon dioxide for causing global warming.
Life is never simple. A lot of people like to eat meat. Globally meat consumption is increasing especially in developing countries. How we are go meeting this increasing consumer demand is not going to be easy.