Scribble

Beef —

Beef is widely recognized as the most climate-damaging of all foods. A 2017 study by the Natural Resources Defense Council on food consumption in the US calculates that each kilogram of beef produces 26.5 kilograms of CO2 emissions -- the highest among all the foods observed in the study, and five times more than chicken or turkey meat.

Animal agriculture is responsible for 14.5% of the world's greenhouse emissions, according to the UN's Food and Agriculture Organization, making it a significant contributor to climate change. Of those emissions, 65% come from beef and dairy cattle.

Reducing beef consumption is an effective way of curbing global emissions. According to the NRDC, Americans now consume 19% less beef than they did in 2005. This is equivalent to a reduction of 185 million metric tons of emissions, or the annual tailpipe pollution of 39 million cars.
But why is beef so bad? "The feed is largely produced using lots of pesticide and fertilizer, which requires fossil fuels," explains Sujatha Bergen, one of the authors of the study. "Also, the digestive system of the cows produces methane, which is 25 times more potent a greenhouse gas than carbon dioxide. And the manure emits additional greenhouse gases."

Jupiterimages

Lamb —

Another ruminant, lamb, comes at number two -- confirming that red meat is particularly resource-intensive and, as such, damaging to the environment. For each kilo of lamb meat consumed, there are 22.9 kilos of emissions, the NRDC study estimates.

Meat production also requires large amounts of animal feed, mainly the resource-intensive corn and soy. The synthetic fertilizer and the manure used to grow these also releases nitrous oxide, a climate-warming pollutant 298 times more powerful than carbon dioxide.

PETER PARKS/AFP/AFP/Getty Images

Butter —

The third most damaging food, by some distance, is butter: one kilo of butter equals nearly 12 kilos of CO2 -- about half as many as beef. It belongs to the same supply chain, making dairy and beef cattle an environmentalist's nightmare.

While Americans have greatly reduced their consumption of red meat in recent years, the NRDC reports that butter and other dairy products such as cheese and yogurt actually enjoyed a surge in the observed period, from 2005 to 2014.

Butter is the most climate damaging of all dairy products because there are several steps involved in producing it that are energy-intensive: "For example, butter production requires separating raw milk into low-fat milk and cream, pasteurizing the cream, cooling the cream, ripening and churning," Sujatha Bergen told CNN.

Riou/Digital Vision/Getty Images

Shelllfish —

Shellfish costs the environment 11.7 kilos of CO2 for every kilo of food produced, just marginally less than butter. Along with milk, pork, and high-fructose corn syrup -- widely used as a sweetener in soft drinks -- shellfish is among the key foods that Americans are eating less of. Overall, changes in the American diet since 2005 have led to a 10% decrease in per-capita climate pollution related to food, according to the NRDC.

Brendon Thorne/Getty Images AsiaPac/Getty Images

Cheese —

Another dairy product, cheese, comes in fifth place with 9.8 kg of emissions per kg produced. "Our list is a an average of several common cheeses," explains Sujatha Bergen, "Cheeses that require refrigerated transport or are flown in from abroad, however, tend to have higher climate impacts."

Joe Raedle/Getty Images North America/Getty Images

Asparagus —

The only vegetable on the list is also the most surprising entry. Asparagus creates 8.9 kilos of emissions per kilo produced, according to the NRDC. But how?

The problem is mostly in the air miles. NRDC's Sujatha Bergen explains: "Much of the asparagus in the United States is flown in from Latin America, which results in greater climate emissions than foods that are transported by trucks. While it's not the only produce item that is flown into the country, a higher proportion of it is transported this way than most other common fruits and vegetables (many of which we import from Mexico). In general, if people are looking to minimize their climate impacts, they should avoid air freighted foods as much as possible."

SAUL LOEB/AFP/AFP/Getty Images

Pork —

One kilo of pork creates 7.9 kilos of carbon emissions. The NRDC estimates that changes in the American diet avoided approximately 271 million tons of climate-warming pollution between 2005 and 2014, roughly equivalent to the tailpipe pollution of 57 million cars for one year. In the list of foods that contributed the most to this reduction, pork is third behind beef and orange juice.

Joe Raedle/Getty Images North America/Getty Images

Veal —

Another entry that belongs to the beef and dairy cattle supply chain, veal has a lower environmental impact than beef because the calves are slaughtered at a younger age, typically at around 20 weeks versus 18 months. Each kilo creates 7.8 kilos of carbon emission, according to the NRDC.

PHILIPPE HUGUEN/AFP/AFP/Getty Images

Chicken —

Eating less chicken meat is one of the contributing factors that have led to a reduction in per-capita emissions linked to food in the US, but poultry still ranks in the top 10, with just over five kilograms of CO2 per kilogram of product.

Courtesy Neil Conway/Creative Commons/Flickr

Turkey —

Turkey has the same carbon footprint as chicken, at around 5 kilos of emissions per kilo of meat.

The NRDC has excluded from this list some foods that most people are not familiar with or are difficult to deliberately avoid, because they are often used in ingredients in other products as opposed to purchased directly by consumers in large amounts. These include: lard and beef tallow (11.92 kg of CO2 per kg of food), dry milk products (10.4 kg of CO2 per kg of food), and other added fats and oils such as palm oil (6.30 kg of CO2 per kg of food).

These are the most climate-damaging foods

CNN —

A new report a British advisory body has called for a 20%-50% cut in the number of sheep and cattle to help combat climate change – adding to the growing international consensus that eating red meat is not only bad for your health, it is also bad for the environment.

Lamb, beef and dairy production accounts for the majority of greenhouse gases emitted by farms in Britain, with sheep and cattle directly responsible for around 58% of agricultural emissions in the UK in 2016, says the report by the government’s Committee on Climate Change (CCC).

The advisory body suggests that a dramatic reduction in the consumption of cow and sheep products could release up to 7 million hectares of grassland, which could instead be planted to create forests and help store carbon.

It recommends that the UK’s land under forestry should increase to 19% from 14%.

The committee also said a reduction in beef and lamb consumption would lead to a rise in the consumption of plant-based food, as well as chicken and pork.

The government’s “Eatwell Guide” for a healthy and balanced diet outlines the proportion of a person’s diet that each food group should provide. The report says that following these guidelines would lead to a dramatic reduction in the amount of red meat eaten by the population, with an 89% reduction for beef and a 63% reduction for lamb. This would also see a 20% decline in dairy products.

The target of reducing sheep and cattle numbers by 20%-50% also relies on people following the recommended diet, with the 20% goal achievable if people replace red meat with chicken and pork. The higher 50% goal would involve people switching to meat alternatives or substitutes.

The report, which has an overarching goal to create a “a new land use policy” that will help mitigate climate change, also includes recommendations to increase Britain’s forested area as well as the restoration of the country’s peatlands and the reduction of flood risks.

“This is a wake-up call for a complacent government that we must completely transform the way we use land, to avoid climate breakdown and make space for nature,” Friends of the Earth campaigner Guy Shrubsole said in a statement.

“As the Committee on Climate Change says, we need to free up land from agriculture by eating much less meat and dairy, and stop landowners burning and degrading peat bogs – our single biggest carbon store.”

Animal farming is responsible for 14.5% of the world’s greenhouse emissions, according to the UN’s Food and Agriculture Organization, making it a significant contributor to climate change. Of those emissions, 65% comes from beef and dairy cattle.

A recent report by the UN’s Intergovernmental Panel on Climate Change emphasized the need for people to consume about 30% less animal products. Eating less meat is one of a number of mitigation strategies suggested by the IPCC to overhaul agricultural and land-use practices, including the protection of forests.

A study last month predicted that as a result of population growth and the continued consumption of large amounts of red meat and processed food in the West, the environmental pressures from the food system could increase by up to 90% by 2050.

CNN’s Meera Senthilingam contributed to this report.

CNN values your feedback

Combat climate change by cutting beef and lamb production, report says

These are the most climate-damaging foods