What does a green diet look like?

The trouble is that, right now, most of our food isn’t produced in a sustainable way. Food as a whole generates 20-30 per cent of global greenhouse gases (GHG), with farming and agriculture alone responsible for 15-25 per cent of GHG emissions. It’s also a major cause of deforestation, overfishing, biodiversity loss, and soil and water pollution. The combined impact means an increase in global warming, extreme weather events, water shortages, and (eventually) food shortages for everyone.

To help preserve the planet, many climate scientists say we need to change the way we produce and consume our food. Luckily, this change can be also good for our wellbeing too.

How do you eat green?

A government initiative called the Green Food Project has identified eight key principles of a healthy and sustainable diet. They are:

1. Eat a varied balanced diet to maintain a healthy body weight.
2. Eat more plant-based foods, including at least five portions of fruit and vegetables per day.
3. Value your food. Ask about where it comes from and how it is produced. Don’t waste it.
4. Moderate your meat consumption, and enjoy more peas, beans, nuts, and other sources of protein.
5. Choose fish sourced from sustainable stocks. Seasonality and capture methods are important too.
6. Include milk and dairy products in your diet or seek out plant-based alternatives, including those that are fortified with additional vitamins and minerals.
7. Drink tap water.
8. Eat fewer foods high in fat, sugar and salt.

This might feel like a lot of changes to make to your diet all at once. Where do you start? One option is to choose the changes that have the biggest environmental impact.

Moderate your meat consumption

Research shows that red meat and dairy products generate the largest amounts of carbon dioxide in the UK diet. But switching to a plant-based diet has been identified as one of the most effective ways to reduce our carbon impact on the planet.

Cutting out, or cutting down, the amount of meat we eat is also good for our health. Figures from the National Diet and Nutrition Survey found we eat, on average, 90.5g of red meat every day. However, eating 90g a day or more has been liked to bowel cancer and other conditions such as high cholesterol and heart disease. Experts advise eating no more than 70g a day, or 500g of red meat a week.

If you don’t want to stop eating meat altogether, you could reduce the amount of beef and lamb you eat. The Committee on Climate Change (CCC) says sheep and cattle produce the most carbon, but replacing them with pork or chicken could cut greenhouse gas emissions by 9%.

Eat more plant-based foods

The WHO and many other public health bodies recommend eating more plant-based foods to help improve our health – but one of the classic arguments against reducing our meat intake is that plant proteins don’t contain the right mix of nutrients. This simply isn’t true, if you get the right balance.

The Association of UK Dietitians (BDA) says, ‘protein quality and quantity is not compromised when switching to more plant-based diets. Plants contain all essential amino acids, and diets entirely based on plant foods that meet daily energy requirements will also meet all essential amino acid requirements’.

When it comes to plant milks, the argument is slightly more complicated. A University of Oxford study found that producing a glass of dairy milk creates nearly three times the greenhouse gas emissions of any non-dairy milks. But producing almond and rice milks in particular can be very water intensive – a single glass of almond milk needs 74 litres of water, which is more than the average shower.

Don’t let this put you off switching to a more plant-based diet. A 2019 review concluded that not only was a vegan diet best for the environment, we could achieve the same carbon impact as going vegan by substantially reducing meat and dairy, rather than cutting them out completely. For the greenest option, choose fortified soya and oat milks, rather than almond, if you do make that change.

Drink tap water rather than soft drinks

Fizzy drinks and fruit juices produce the third largest amount of greenhouse gases in our diet but tap water generates one of the lowest, along with tea and coffee. This is because soft drinks need more energy to produce and transport, while fruit juices require a lot of fertilisers and pesticides to grow the fruit in the first place.

When you add in the health benefits, the argument is even stronger for ditching fizzy drinks. Many soft drinks have been associated with obesity and diabetes, prompting governments across the globe to introduce a sugar tax on certain soft drinks. The jury’s still out on whether this tax is effective enough to stop people drinking them.

When experts talk about replacing soft drinks with water, they don’t mean bottled water. Plastic bottles are now one of the greatest polluters on our planet, so swapping a bottle of cola for a bottle of water won’t reduce the amount of plastic we throw away. Sticking to tap water and always carrying a reusable bottle is one of the best ways to look after yourself and the planet.

Is a green diet worth it?

Environmental experts have run the numbers and concluded that if everyone in the UK simply ate a healthy, balanced diet with five portions of fruit and vegetables a day, and little to no sugars or processed foods, we could cut our national carbon emissions by 17 per cent. If we then cut down on animal products, upped our fruit and veg intake, and ate more cereals, we could make further greenhouse gas reductions of around 40 per cent.

The BDA says that making these changes could add nearly 18 million years of healthy life – cutting the days lost to conditions like diabetes, bowel cancer or heart disease – to the current UK population as a whole. Even better, all this can be achieved without following some bizarre new food fad. A healthier you and a happier planet means the green diet may be the only diet that we’ll ever need.

More on sustainability

10 ways to cut your carbon footprint
The facts about food miles
6 pieces of packaging to avoid
10 ways to eat out sustainably
How to reduce food waste
What biodegradable really means
Is your diet contributing to water scarcity?
How to compost food at home
8 ways to be a better recycler
What are greenhouse gases?
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