The diets with the biggest and smallest carbon footprints -

The effects of climate change are now well known and evident. As a result, more and more people are becoming aware of the need to take action, not only at a global scale but also individually. This usually means recycling, opting for second-hand products, travelling by public transport, buying local products, and adopting a more sustainable diet. A 2023 study from Tulane University in New Orleans analyzed the carbon footprint of the six most common diets. The six diets analyzed were: vegan, lacto-ovo vegetarian, pescatarian, keto, paleo, and omnivore.

Click on to discover how these diets ranked. 

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Food -

Our diet, including everything involved in producing, processing, and transporting our food, generates more than a third of the planet's total greenhouse gas emissions. Food-related emissions can be divided into the following four categories. 

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Land emissions - Those from land use, such as agriculture and livestock farming, as well as the various associated land disturbances and activities: deforestation and water pumping.

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Energy emissions -

Those generated by the consumption of energy to produce, process, package, and transport food.

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Waste treatment emissions -

Emissions related to the treatment of waste and surpluses.

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Industrial emissions -

Industrial emissions result from the production of various chemical compounds, such as plastics for packaging, preservatives, fertilizers, and insecticides. Now, let's take a look at the six diets analyzed for their carbon footprints. 

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6. Vegan diet -

According to the study, the vegan diet has the smallest carbon footprint. It generates 1.52 pounds (0.69 kg) of CO₂eq/1000 Kcal. 

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Vegan diet -

This makes sense as animal-derived foods account for 82% of the carbon footprint. 

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Vegan diet -

This means, replacing animal-derived foods with plant-based sources of protein and fat, such as legumes, nuts, and seeds would dramatically reduce the environmental impact of our diets.

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Vegan diet -

In fact, it has been estimated that if animal-based foods were eliminated and replaced with plant-based foods, diet-related emissions would be reduced by more than 73%. 

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5. Lacto-ovo vegetarian diet -

The diet with the second-smallest carbon footprint is the lacto-ovo vegetarian diet. It generates 2.55 pounds (1.16 kg) of  CO₂eq/1000 Kcal. 

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Lacto-ovo vegetarian diet -

Unlike the vegan diet, it allows the consumption of eggs, milk, and their derivatives, which explains its greater impact. 

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Lacto-ovo vegetarian diet -

The dairy sector alone is responsible for 4% of global greenhouse gas emissions. 

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Lacto-ovo vegetarian diet -

Nevertheless, a lacto-ovo vegetarian diet is still a carbon-friendly choice. 

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4. Pescetarian diet -

The pescetarian diet, characterized by predominantly plant-based foods with fish and seafood, is the third least polluting diet. It generates 3.65 pounds (1.66 kg) of CO₂eq/1000 Kcal. 

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Pescetarian diet -

Compared to other animal-derived food, such as pigs and poultry, seafood has a lower carbon impact. This is especially true if you choose to eat shellfish and small fish such as anchovies and sardines. 

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Pescetarian diet -

Other fish and seafood, caught by local rather than deep-sea fishermen, avoid emissions from transportation and from preserving the catch during the journey. 

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Pescetarian diet -

However, aquaculture fish, such as salmon and gilt-head bream, or farmed crustaceans, require feed in the form of food pellets and oil. Therefore, they release more waste and emissions into the environment.

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3. Omnivore diet -

The omnivore diet includes both plant and animal foods. Generating 4.91 pounds (2.23 kg) of CO₂eq/1000 Kcal, the omnivore diet has the third-largest carbon footprint.

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Omnivore diet -

The study found that 86% of the US population adheres to an omnivore diet. 

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Omnivore diet -

It has also been estimated that producing the amount of meat consumed annually by a US citizen generates more than 4,409 pounds (2,000 kg) of greenhouse gases per year.

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Omnivore diet -

Eliminating meat consumption one day a week would reduce this amount to 3,527 pounds (1,600 kg). 

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2. Paleo diet -

The paleo diet has the second-highest climate impact because it's characterized by a high consumption of land-based meat. 

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Paleo diet -

The paleo diet generates 5.77 pounds (2.62 kg) of CO₂eq/1000 Kcal.

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Paleo diet -

Preferring lean meats and fish, the paleo diet restricts the intake of many plant-based products. This diet also excludes cereals, legumes, dairy products, sugary vegetables, and all types of processed foods.

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Paleo diet -

In addition to land-based meats and fish, the paleo diet allows the consumption of nuts, fruits, seeds, and some vegetables. 

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1. Keto diet -

The keto diet generates the largest carbon footprint due to its high protein and fat intake and very low carbohydrate consumption. And these proteins are mainly of animal origin.

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Keto diet -

In fact, the keto diet generates 6.41 pounds (2.91 kg) of CO₂-eq/1000 Kcal. That's more than four times worse than a vegan diet.

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Keto diet -

Foods derived from land animals are by far the largest contributors to the carbon footprint of our diets. When we eat plant products, we are primary consumers. However, when we eat animal products, we are secondary consumers.

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Keto diet -

This means there's an intermediate stage, and all the carbon-emitting processes are duplicated.

Sources: (Euronews) (OpenMind)

See also: Environmentally destructive foods we all consume

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