NUTRITION

Learn more about the connection between food waste and climate change.

How does food waste impact climate change?

An illustration of the planet earth in the center of the picture with blue background. The earth is circled by six orange and yellow carrots.
You might be curious about how food waste can impact climate change. Well, the natural process of food production includes the release of greenhouse gases. But because food is now a global commodity that is carried around the globe, the situation is uneven. Just consider the items in your trolley: Chilean grapes (12,000 km), South African baby carrots (10,000 km), Spanish broccoli (1500 km), Brazilian steak (10,000 km), and so on.
The good news is that food waste is one of the easiest causes of climate change to address and one where everyone can have a positive impact in their everyday life. FACTS
  • The agri-food system and climate change are interlinked and affect each other.
  • The agri-food chain affects the environment through greenhouse gas (GHG) emissions, as well as using large amounts of water and land.
  • GHGs are emitted when forests are cleared to make way for farms, ruminant animals digest feed, fossil fuels are used to transport and operate farm machinery, and waste is disposed of in landfills.
  • Animal products have the largest carbon and water footprints, while plant foods are a much more sustainable alternative.
  • Although the highest emissions occur during production, in developed countries much of the food is wasted at consumer level.
  • The winter holidays are the time of year when we tend to buy, cook, eat and waste a lot of food, but this year we can make small changes to reduce our negative footprint.
Have you ever wondered about the origins of your food, the resources used to make it, the distance it travelled to get to your plate, or the carbon impact of your diet? Though it may be less evident, the daily food decisions we make have a direct effect on the environment and have global repercussions. The food system and climate change are closely related, with each having an impact on the other. What do we consume today to support the environment and maintain our health? The best diet for lowering our carbon footprint varies somewhat depending on where we live. A few greenhouse gases (GHGs) are released during processing, transit, and commerce, as we’ll see towards the end of the essay.
Top view on a toasted slice of bread with holes in it laying on a grey stone-like surface. One hole reveals the words "Food Crisis"
A pot of fresh basil, a bottle of olive oil and a bowl of red tomatoes are placed on a wooden tabletop. A brick wall can be seen in the background.
Most emissions come from manufacturing rather than transportation, thus it is important to understand which foods we should avoid or consume less of. Ruminant meat (from cattle, sheep, and goats) produces the most greenhouse gases (GHGs) of any type of food. Compared to beans, nuts & seeds, and soybeans, beef has around 316 times the amount of greenhouse gases (GHG) per serving. These estimates consider emissions from the deforestation of forests to produce palm and soybean oils, showing the negative environmental effects of a diet high in meat (and to a lesser extent, dairy). While being rarely eaten in Romania, insects are a more environmentally friendly source of protein. Although forage fish like sardines and herring also produce only little amounts of GHGs, growing fish requires far more water than growing other types of food.
The graph below estimates the contribution of each food to GHGs, with beef, lamb and dairy leading the way. Depending on how and where the food is produced, its impact varies. Vegan diets tend to have the lowest per capita GHG footprint in 97% of the 140 countries included in this study by the Johns Hopkins Center for a Livable Future. For a US resident, for example, even substantially increasing the amount of plant foods consumed to replace animal nutrients would still leave emissions considerably lower than for an omnivorous diet, due to the lower GHG footprint per kilocalorie of most plant foods.

According to the same study, if the entire world adopted the diet of rich countries (high-calorie, meat- and dairy-rich), GHG emissions would increase by 135% and water consumption would increase by 47%. However, this does not imply that the entire population must become vegan. Dietary adaptation must consider not only environmental impact, but also location, culture, accessibility, nutrition, and personal preference. A flexitarian diet, based mainly on plant sources, may include modest amounts of animal products. The so-called ‘planetary health diet’ recommends a maximum consumption of 98g of red meat (pork, beef, or lamb), 203g of poultry and 196g of fish per week. There is enough research to show that excessive consumption of red meat and processed meat is also harmful to the human body, so we should eat at least 125g of dried beans, lentils, peas, and other nuts or pulses per day to meet our protein needs. It is critical to consume more fruits and vegetables, as well as wholegrains, and to maintain a varied diet to obtain all the nutrients we require.
Table which shows different food items and shows their impact on Greenhouse gas emissions. A chocolate bar from the deforested raisnforest emits more than a serving of low-impact beef. A portion of the highest-impact vegetable proteins emits less than the lowest-impact of animal proteins.
GHG emissions/portion of food (source: BBC, infographic created
after Poore and Nemecek)

A 'greener' winter holiday

HAVE YOU EVER THOUGHT ABOUT THIS?

We’re used to associating affluence with wealth, and Christmas is one of those times when we buy and spend in excess. Regardless of the category, we might try to buy and waste less, whether it’s electronics, clothes, or food.

In addition to the carbon footprint of production, our food continues to emit GHGs especially when it ends up decomposing in landfill. In the European Union, 20% of all food produced is lost or wasted, with 70% of this happening in households. If we were to integrate all the food wasted worldwide into a ranking of the largest emitters of GHGs, it would rank 3rd, after the US and China.

Food waste is not only a waste for the environment, but also for each of us. A study by Food Waste Combat shows that in Romania we spend around 40% of our income on food, of which 33-50% ends up in the bin. Basically, out of 3 shopping bags, at least one is useless.

Top view on slices of different fruits, herbs, and vegetables that are together spaping the form of a pyramid.
The most effective way to avoid waste is to buy less. We have a habit of buying lots of products before Christmas, although shops sometimes reopen on the first or second day of Christmas. If we bought less and more often, we could avoid waste. As the graph below shows, in Romania we tend to throw away both cooked food and fresh food such as vegetables and fruit. This year, we can make the winter holidays more balanced by shopping, cooking, eating, and wasting less. Eat less meat (especially beef), don’t overeat, and don’t waste food are three things that can help us reduce our carbon footprint. For the Christmas menu, we can try to make small changes without affecting the tradition we have become accustomed to. For example, replacing a meal with a vegan alternative (some ideas here), or baking a cake without animal products (like this vegan cake) are small steps towards a more environmentally friendly Christmas. Another change of perspective we can adopt is to consider meat and animal products as luxury foods.
Climate change food calculator: What’s your diet’s carbon footprint?
In the BBC News article: Climate change food calculator: What’s your diet’s carbon footprint?
Written by Nassos Stylianou, Clara Guibourg and Helen Briggs, the authors state that, according to recent scientific studies, avoiding meat and dairy products is one of the biggest ways to reduce your environmental impact. Switching to a plant-based diet can help fight climate change. But what is the difference between beef and chicken? Does a bowl of rice produce more climate warming greenhouse gases than a plate of chips? Is wine more environmentally friendly than beer?

To find out the climate impact of what you eat and drink, choose from one of the 34 items in our calculator and pick how often you have it. https://www.bbc.com/news/science-environment-46459714
All figures for each food in the calculator are global averages. If you cannot view the food calculator, click to launch the interactive content.   Design by Prina Shah, development by Felix Stephenson and Becky Rush.
Further readings