Is a vegan diet better for the environment?

The charity behind Veganuary says that the 350,000 people who gave up animal products in 2020’s event could have saved the equivalent of taking 160,000 cars off the road in greenhouse gas emissions, or cutting 400,000-500,000 single flights from London to Berlin. So, imagine the benefits if everyone went vegan.

How is a vegan diet better for the planet?

One answer is the huge environmental cost of industrialised animal farming. Today, the UN says meat and dairy (farmed livestock) accounts for 11.2% of manmade greenhouse gas emissions. But, if we all went vegan, scientists believe the world’s food-related emissions might drop by 68% within 15 years, limiting global warming.

Sound good? Well, it is. But, as always, the devil’s in the detail.

Just as it’s possible to be vegan and still eat unhealthily, there are some vegan foods that aren’t great for the planet, either.

For more tips on how to eat a balanced vegan diet, read our nutritionist guide or check the NHS website.

If you’re vegan (or thinking about making the switch) learn how to keep your carbon footprint as light as possible.

Are plant-based milks bad for the environment?

Did you know it takes 74 litres of water to make a single glass of almond milk? That’s more than a typical shower. Rice milk is also quite ‘thirsty’, requiring 54 litres of water per glass. These numbers are still low compared to dairy milk, but they’re far higher than soya or oat milks. Plant-based milk alternatives are also not a nutritionally comparable swap, although some consumers believe them to be.

The following table shows how alternative milks compare when it comes to carbon emissions, land use and water use:

Are avocados bad for the environment?

Whether you prefer them smashed on toast or folded into a wrap, avocados have been said to be another water-hungry crop. It’s tricky to pin an exact ‘water footprint’ on the little green fruit, but some sources suggest it takes 227 litres (60 gallons) of water to grow a single avocado, while others put it at 824 litres (183 gallons) per kilogram. That said, these figures don’t take into account advances in cooling and irrigation methods implemented by avocado growers, which appear to have led to reductions in the amount of water used per hectare.

If you want to buy avocados sustainably, one option is to choose those certified by a scheme such as Fairtrade or Equal Exchange. And, if you want to benefit from the nutritional benefits of avocados, such as B vitamins, healthy fats and vitamin E, there are food alternatives.

As food journalist Joanna Blythman explains: "If you’re buying [an avocado] for vitamin E, sunflower seeds are a richer source. If you’re hunting down vitamin K, you’ll find heaps in broccoli and cabbage. For monounsaturated fats, turn your attention to extra virgin olive oil or olives. To pack in the folate/vitamin B9, go for lentils and cauliflower."

However, what you won’t replace is avocado’s unique unsaturated fat and water-based matrix, which makes its fat-soluble nutrients, including carotenoids, much easier for us to absorb from both it and the plant foods we enjoy the avocado with.

Is soya bad for the environment?

Packed with vitamins, soya beans are also incredibly versatile. You’ll find them in tofu, flour, meat-free burgers, veggie sausages and much more.

So far, so great for vegans. But, according to the WWF, soy is the second-largest agricultural driver of deforestation worldwide after beef: "From the US to the Amazon, forests, grasslands and wetlands are being ploughed up to make room for more soy production." This has led to a persistent myth that eating soy is worse for the planet than eating beef.

In fact, only 6% of soy is grown for human consumption in products such as soy milk, tofu and edamame, while roughly 81% is grown to feed livestock – mainly cows, pigs and chickens. And, when it comes to deforestation, soy accounts for just a fraction of Amazon deforestation, compared with 80% for cattle farming.

There has also been a ‘soy moratorium’ in place in Brazil since 2006. This agreement between major soya companies not to buy any beans grown on recently deforested land has led to an 84% decrease in Brazilian Amazon deforestation. We’ll raise a glass of soya milk to that.

Is palm oil bad for the environment?

From soap to sweets, margarine to make-up, palm oil is in around half of all supermarket products – and it’s a common ingredient in vegan alternatives, such as non-dairy ice creams and cheeses.

In theory, there’s no problem with cultivating palm oil. The problem is that it’s often grown irresponsibly – and the rapid rise in palm oil production in south-east Asia in particular has caused huge deforestation and pushed the orangutan towards extinction. Environmental campaign group Rainforest Rescue claims an area of forest the size of 300 football pitches is lost in Indonesia every hour to palm oil farmers.

Though some critics aren’t convinced about its environmental credentials, there is a sustainable palm oil scheme and a growing number of global brands have pledged to produce more sustainable palm oil, including L'Oréal, Nestlé and Unilever.

Is imported fruit bad for the environment?

Evidence shows that vegan diets tend to have far lower carbon, water and ecological footprints than those of meat- or fish-eaters. One Italian study found two vegan participants with extremely high eco-impacts, but this turned out to be because they only ate fruit.

As Helen Breewood, research assistant at the Food Climate Research Network (FCRN) explains, imported fruit can be a problem because it’s often air-freighted into the UK. This increases its carbon footprint. However, ‘food miles’ alone aren’t necessarily the best measure of sustainability – some intensively grown local produce can have a bigger footprint than imported food.

Helen adds that there are still a lot of knowledge gaps. For example, there is currently little research into newly fashionable vegan foods – such as jackfruit, often used to create vegan ‘pulled pork’ – so it’s hard to judge their environmental credentials.

What will a sustainable diet look like in the future?

What does all this mean for our future eating habits? Some experts point to the rise of technology and plant-based, lab-grown or 3D-printed meats – coming soon to a restaurant near you. These have the potential to dramatically slash the environmental footprint of food. Bill Gates even calls them the ‘food of the future.’

Other experts believe that living creatures will continue to feature in our future diet, but they won’t be farm animals. Though not vegan, of course, insects are often rich in vitamins and minerals including iron and zinc, as well as essential fatty acids like omega-3. They're also low in fat and a good source of protein.

Not a fan of pan-fried crickets? Not a problem: the EAT-Lancet Commission led by Dr Walter Willett, professor of medicine at Harvard University, was created in 2019 to develop a diet that’s good for both us and the planet. As the report notes: "Food is the single strongest lever to optimise human health and environmental sustainability on Earth. However, food is currently threatening both people and planet."

But, the resulting ‘planetary health diet’ is not vegan. Dr Willett says: "Global consumption of fruits, vegetables, nuts and legumes will have to double, and consumption of foods such as red meat and sugar will have to be reduced by more than 50%." In reality, this looks like a flexitarian diet – largely plant-based, with very modest amounts of meat, fish and dairy.

Of course, you can choose not to eat meat, but this isn’t possible for everyone – some global populations depend on agro-pastoral livelihoods and animal protein from their livestock. For that reason, the commission hasn’t recommended going vegan, but instead suggests a whole raft of changes to the way we grow, transport, eat (and waste) all the food produced on the planet.

So, in short, my opinion is yes – a vegan diet is better for the environment. But, it’s not the only way we can help reduce carbon emissions, deforestation, water scarcity and decreasing biodiversity on the planet. Still, definitely something to consider next time you’re out shopping for dinner.

Enjoyed this? Now read:

What is the planetary healthy diet?
What is a flexitarian diet?
A balanced vegan diet
What would the world look like if everyone went vegan?

Paul Allen is a former BBC environmental editor and a director at Lark. Find him on Twitter @larkingly.

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