Food production requires a lot of energy: Fuel, power for machines, processing and refrigeration.
Fertilizer use generates nitrogen turnover in the soil, leading to emissions of nitrous oxide, which is 298 times stronger than greenhouse gas than CO₂.
Domestic intestinal gas contains methane, which is a 25 times more powerful greenhouse gas than CO₂. Methane is also released from rice fields and manure tanks.
A field stores less CO₂ than forest.
Drainage causes carbon in the soil to bind with oxygen to form CO₂.
Greenhouse gas emissions are distributed as follows:
- Energy sector: 35 per cent
- Agriculture and food production: 25 per cent
- Industrial sector: 21 per cent
- Transport: 14 percent
- Build: 6.4 percent
Source: International Panel of Climate Change, Synthesis Report, 2010.
A new study shows that emissions from the food industry will increase by 80 percent by 2050 – if we do not change course.
But vegetarian food can stop the unfortunate development and at the same time lower our risk of type 2 diabetes.
There are important results, say two Danish experts.
- The study shows that two flies can be smacked – reducing greenhouse gas emissions and improving health, says Thomas Meinert Larsen, associate professor at the Department of Sport and Nutrition at the University of Copenhagen. He also researches the relationship between diet, health and climate.
Vegetarian food is good for health and best for climate
Vegetarian food leads to less greenhouse gas emissions than any other type of food – and is also associated with a lower risk of diabetes.
However, climate scientist Jørgen E. Olesen believes that the main responsibility lies with the politicians.
- Changes in the diet will not happen without political measures. For example, there may be higher taxes on meat, says Olesen, who is a professor at the Institute of Agroecology at Aarhus University and a former member of the UN Climate Panel.
Fish no better than pig
The research group from the University of Minnesota compared three different types of diets – vegetarian diets, vegetarian diets with fish and Mediterranean diets.
They studied population surveys from 100 countries in the world, as well as studies of the emissions of greenhouse gases from the food industry.
The result shows that:
The vegetarian diet is associated with a 42 percent lower risk of type 2 diabetes than a regular Western diet. Vegetarian food with fish reduces the risk by about 25 percent, and a Mediterranean diet by 18 percent.
All three types are associated with a 20 to 25 percent lower risk of getting cardiovascular disease, with the Mediterranean diet being the best.
All three are associated with an 8-12 percent lower risk of cancer, but here the vegetarian diet with fish is the best.
The overall picture is still unclear
The study also shows that the production of 100 grams of fish actually emits as much greenhouse gases as the production of 100 grams of pork.
However, the largest source of greenhouse gas is beef, with three times the emissions of pigs and fish.
- That’s a dilemma. Vegetarian diet is better in relation to diabetes, while fatty fish has a positive effect on cardiovascular disease. But fish stress the climate, says Thomas Meinert Larsen.
However, there is every reason to be careful about population surveys, Larsen points out.
- It is difficult to say with certainty why the different diet types affect us differently. It is possible that the population surveys have not been good enough, says Larsen.
- Population surveys are large and look at trends, but there is always a risk that we misinterpret them. Then you find only coincidence in statistics, not cause and effect. But on the other hand, we must act on the basis of the knowledge we have.
He also points out that you can eat some meat without compromising your health. It’s just as much about exercise, and what else you put in your mouth, Larsen thinks.
Overpopulation is the biggest threat
Meat production is the main cause of emissions in the food industry.
- The population of the world is increasing by 80 million people every year. Therefore, greenhouse gas emissions will also increase. Politicians should make a deal: The industrialized countries will reduce their CO 2 emissions if developing countries keep birth rates down. That would really make a difference, says Larsen.
Although more food is produced, leading to larger emissions, the emissions for each product are declining, Jørgen E. Olesen notes.
- The industry is constantly streamlining. That’s the positive. But it cannot keep up with rising demand. At the same time, more and more former developing countries are being industrialized, with greater consumption, including food, says Olesen.
The energy sector is more important
It is the energy sector that emits the largest amount of greenhouse gases – 35 per cent of the total – but the food industry comes just behind, says Olesen.