Mythbusters: 8 common misconceptions about British farming and the environment

Farming has a role to play in tackling climate change because of its contribution to greenhouse gas emissions (GHGs).

But that contribution is often overstated by anti-farming lobby groups and sections of the wider media that may have a vested interest in turning farming into a pariah.

Some of the claims made are so far from the truth that public actions based on the disinformation could even be harmful to the environment and human health.

See also: Mythbusters: 8 common misconceptions about antibiotics

Farmers Weekly has teamed up with the Sustainable Food Trust (SFT) to look at eight of the common claims made in order to debunk them as myths and replace them with facts.

1. Water use on dairy farms is unsustainable

Claim: It takes 1,000 litres of water to produce 1 litre of milk

This figure is widely used in mainstream media. However, a study by Cranfield University found that only 7.5-8 litres of water (less than 1% of the claimed amount) is used on UK dairy farms to produce one litre of milk.

Richard Young, SFT policy director, explains the Cranfield figure relates to mains water.

He says that other water used on farms is from sustainable, cyclical sources such as rain, and is not as relevant in a country such as the UK – which has relatively high annual average precipitation – as in the US, for example, where forage and feed crops are often irrigated. 

2. Greenhouse gas emissions from farming are higher than any other sector

Claim: Food production accounts for 30% of emissions, which is higher than transport

The 30% figure is often wrongly attributed to emissions from UK farming activities alone. But the Office for National Statistics (ONS) estimates emissions attributable to UK agriculture are about 10% of the national total.

Of the 10% roughly 6% is attributable to livestock farming, the ONS states.

Robert Barbour, SFT senior researcher, explains that the 30% covers everything related to food production and consumption in the UK, including processing beyond the farm gate, transport and retail costs.

It also covers emissions from imported food, feed, fertiliser and even equipment used in food production.

3. Beef has the highest carbon footprint of all food types

Claim: Beef produces 50kg of greenhouse gas emissions per 100g of protein 

This figure is, in fact, an average for global production covering a huge variety of production systems.

When deforestation is factored into calculations – for South American cattle on converted rainforest land, in particular – the figure can be many times greater than the global average.

Unfortunately, it is figures for systems such as these that are inflating the average and are wrongly touted as a marker for all beef production.

Emissions from British grass- and grass silage-fed beef, which accounts for more than 90% of UK output, are far lower.

According to the SFT, a more realistic figure is 10-14kg of carbon dioxide per kilogram of meat from dairy herds and between 15-20kg of carbon dioxide equivalent per kilogram of meat for suckler herds, with some achieving even lower figures than this.

Critics also often overlook the carbon sequestration by hedges, soils and trees, which cut net emissions on grassland farms.

4. We must cut UK livestock numbers to reduce emissions

Claim: Reducing livestock numbers is as important as cutting fossil fuel use

The UK has already seen the national cattle herd reduce by about 20% since the early 1990s, Defra figures show. This has helped reduce farm methane emissions by about 13%, according to the SFT.

However, while UK demand for red meat remains stable, cutting livestock numbers further could see supply run short.

This could create a gap that would be filled by imports with higher carbon-related emissions, says Mr Barbour.

It is important that we don’t cut grazing livestock levels too far, because this could ultimately raise global emissions, he suggests.

5. Too much land is devoted to livestock production

Claim: Grazing land should be used for arable growing 

A frequent claim is that too much land is used for livestock production. It should instead be switched to crop growing to cut emissions and feed more people, say critics.

Roughly two-thirds to three-quarters of farmland is used for livestock and dairy production, according to the ONS and the United Nations Food and Agriculture Organisation (FAO).

But although the facts appear to back up the point, the argument sidesteps a key fact – 65% of the grasslands are unsuitable for arable growing.

On steep slopes, uplands, protected ridges and furrows, common land and much more, only sheep and, in some areas, cattle can turn grass into a protein crop for humans.

Reverting to tree growing on these areas would only deny the world a sustainable protein source.

Less well understood by critics are areas that appear to be suitable for arable production, but where high rainfall or heavy, poor-quality and acidic soils preclude crop growing.

Changing to arable growing would be inefficient on this land, with lower yields and increased crop failures.

Farming the land would require greater dependence on burning fossil fuel for tillage and using more chemicals to combat pests and disease. 

Mr Young also points out that ploughing up grassland for arable causes soil carbon and nitrous oxide losses to the atmosphere. Over 35 years about 40% of the soil carbon is lost.

For a fertile soil with a good organic matter level, this averages about 7t carbon dioxide/ha/year, with higher losses initially, gradually declining over the period.

6. Vegan diets are better for the environment

Claim: Switching to a vegan diet reduces your carbon footprint by 73%

A recent Advertising Standards Authority ruling banned adverts about a plant-based burger that claimed to be better for the environment than its meat alternative.

The authority found that ingredients in the plant burger had been sourced from around the world, incurring carbon use in substantial transport distances.

It concluded that the carbon footprint was potentially higher than locally reared, grass-fed beef.

There is a huge variation in ingredients sourced for meat-based and vegan diets.

A blanket statement that switching to a vegan diet is better for the environment is difficult to justify.

For example, a vegan meal that is based on locally sourced seasonal vegetables will undoubtedly have a lower carbon footprint than beef imported from South America.

But the reverse can be true. Many vegan food products rely on rice, palm oil or soya grown on deforested land, which carry a high carbon footprint.

Figures from the Agricultural Industries Confederation (AIC) show soya beans from countries in South America incur up to 6,573kg of carbon dioxide/t of product.

Rice from Asia is estimated to produce 2,168kg carbon dioxide/t, while Indonesian palm oil produces 1,422kg carbon dioxide/t.

These figures are all relatively high due to the calculated effect of land use change such as deforestation. US-based soya bean and rice only produce 465kg and 404kg carbon dioxide/t, respectively.

7. Vegan diets are healthier than meat-based diets

Claim: Red meat doubles the risk of cancer

A common claim is that red meat is bad for human health. A number of studies have claimed that eating red meat increases cancer risk by 17-100% and should be cut completely from diets.

However, scientists and report authors have raised concerns about the potential samples used, which may not have taken into account whether the meat was fresh or processed, as well as other behavioural factors such as smoking, alcohol consumption and exercise levels.

The World Cancer Research Fund International does acknowledge an increased risk from eating red meat, but it only recommends limiting meat consumption to 350-500g/week rather than cutting it out altogether.

Meanwhile, longevity studies have failed to show that vegetarians and vegans live longer than their meat-eating counterparts.

A recent research paper by Wenpeng You et al featured in the International Journal of General Medicine showed that life expectancy in meat and dairy consumers was higher.

It concluded that meat in the diet may be providing energy and vital nutrients that were otherwise unavailable from plant-based nutrition.

The AHDB also recently highlighted figures showing that milk and meat contain between seven and nine important micronutrients.

Red meat includes vitamin B12, which protects immune systems and is not naturally available in plant-based food, the AHDB suggests.

8. Soya should be fed to people, not animals

Claim: 97% of soya goes through an animal; it should go through humans first

Figures show that the amount of soya used for animal feed is far lower than the 97% figure commonly claimed by lobby groups.

Of the total 3.2m tonnes imported into the UK annually, about 2.4m tonnes, or 75%, is used as livestock feed, according to AIC statistics.

However, this is not the whole story. Most soya beans are processed into two components – soya meal and soya oil – with only about 6% of whole soya beans used directly for human food.

About 80% of the oil goes into food, with the rest mostly used for biodiesel. With meal accounting for at least 80% of the weight, it is the more valuable part.

But the food industry depends on the oil for a wide range of processed foods, and you cannot have one without the other.

The AIC data also points to good sustainability for soya meal used on UK farms, with 57% sourced from regions in north and south America with no risk of deforestation.

A further 37% is deemed to be farmed at low risk of deforestation.