Sustainable Diets: Good For You & Good For The Planet

Urgent Need for Change

Currently, our food systems account for nearly a third of total greenhouse gas (GHG) emissions, as well as being the leading cause of deforestation, biodiversity loss, soil degradation and water pollution⁽¹⁾. With the world population projected to reach 9.8 billion by 2050, our current methods of producing and consuming food are simply unsustainable. Additionally, we are seeing a sharp rise in the prevalence of chronic disease – largely driven by modern diets, dominated by ultra-processed food, high in unhealthy fats, salt and sugars.

Without action, the next generation will inherit a planet that is severely degraded and where much of the population will increasingly suffer from malnutrition and preventable disease. Addressing this crisis requires a major shift in our approach to food, placing sustainable diets at the forefront to protect both human health and the environment.

 

What is a Sustainable Diet?

Put simply, a sustainable diet is one that is good for you and good for the planet. At its core, a sustainable diet prioritises four essential goals:

• Low Environmental Impact: minimises greenhouse gas emissions, reduces pollution, and limits the use of vital resources like water and energy.
• Protects Biodiversity & Ecosystems: embraces practices that support ecosystems and preserve biodiversity at every stage of the food chain.
• Nutrition: provides essential nutrition to promote well-being and optimal health.
• Optimises Natural Resources: focuses on crops and farming practices that enhance soil health, conserve water, and promote regenerative agriculture.

Adopting sustainable diets has become an urgent necessity to reduce our environmental impact, combat global warming, and alleviate pressure on our planet’s resources. Achieving this shift requires commitment across the board – from farmers to global corporations and governments. But what can you do as an individual?

In this article, we’ll explore the key elements of a sustainable diet and share practical, eco-friendly tips you can start using today to make a difference.

 

More Plant Foods

A significant proportion of the population is not consuming enough plant-based foods, with only 27% meeting the 5-a-day fruit and vegetable recommendation⁽²⁾. This low intake has tangible health consequences: around 30% of the population is deficient in essential micronutrients like vitamins, minerals, and antioxidants, which is contributing to the rise in chronic diseases⁽³⁾.

To address this growing health issue, increasing plant-based food consumption is crucial. According to a report by the EAT-Lancet Commission, a sustainable diet should ideally consist of more than 50% plant-based foods, like fruits, vegetables, nuts, seeds, herbs, spices, and whole grains⁽⁴⁾. While this recommendation is slightly higher than current UK guidelines, it closely aligns with the Eatwell Guide, which also encourages basing meals around plant foods to promote balanced nutrition and long-term health⁽⁵⁾. Not only does a plant-rich diet improve health outcomes, but it is also far less taxing on the environment compared to a diet heavy in animal products, helping to reduce greenhouse gas emissions and resource consumption.

A practical way to adopt a more sustainable diet is to diversify the types of plant foods we consume. Current guidance from research like the American Gut Project in the US and the Zoe Project in the UK suggests eating 30 different plant foods each week. This diversity is beneficial to gut health, lowers inflammation, and contributes to overall well-being. By eating a variety of plants, we also promote environmental sustainability by supporting diverse ecosystems and reducing dependence on monocultures.

At present, our diets are overly reliant on a very limited range of foods, with over 75% of our intake derived from just 12 plant and 5 animal species. Despite the discovery of 20,000 to 50,000 edible plant species, only 150–200 are regularly consumed by humans⁽⁶⁾.This limited range or “dietary monotony” is not only bad for our health and limits the range of nutrients and antioxidants we consume, but it also reduces our agrobiodiversity, putting a huge strain on resources and the environment.

In response, WWF and Knorr have developed the Future 50 Foods report, identifying 50 highly nutritious, sustainable foods. These include categories like beans, sprouts, leafy greens, and root vegetables, each selected for its nutritional density, resilience in challenging growing conditions, and ability to improve soil and air quality. By embracing a wider array of these sustainable foods, we can adopt diets that better support both human health and the planet. This shift toward diverse, plant-rich diets is essential in creating a sustainable, resilient food system that benefits people and the environment alike.

A sustainable diet prioritises plant-based foods, which naturally reduces the need for animal-based foods. Animal agriculture, particularly livestock farming, is a significant source of GHG emissions, with livestock releasing substantial amounts of methane – a gas up to 34 times more harmful to the atmosphere than carbon dioxide. By lowering our consumption of animal products, we reduce the demand for livestock, which in turn decreases GHG emissions and lessens the overall environmental impact.

Livestock production also consumes extensive resources. Currently, animal agriculture uses 77% of global farmland but provides only 18% of our dietary calories⁽⁷⁾, reflecting an inefficient resource-to-output ratio. In contrast, plant foods - especially grains - are far more efficient, requiring much less land and water. Additionally, unlike livestock, plants absorb carbon dioxide from the atmosphere, contributing to a net reduction in GHG emissions.

Shifting towards plant-based foods not only supports a healthier diet but also significantly reduces the strain on environmental resources, making it a key component of a sustainable diet.

 

Sustainable Sourcing

While completely eliminating animal-based products may not be the sole solution, making more sustainable and conscious sourcing decisions is key. This applies to both animal products and plant-based foods.

Fishing practices, in particular, are under increasing pressure, with 90% of global fisheries either fully exploited or overfished⁽⁸⁾. As a result, the marine vertebrate population has been halved, creating a significant strain on fish stocks, especially since billions of people rely on seafood as a primary protein source. To support more sustainable fisheries, it is important to prioritise certified sustainable seafood, such as products carrying the Marine Stewardship Council (MSC) certification. This ensures that the seafood you consume is caught using methods that protect marine ecosystems and fish populations.

Just as we should diversify our plant-based food choices, we should also expand the variety of seafood we consume. In the UK, 80% of seafood intake is dominated by just five species - cod, haddock, salmon, tuna, and prawns - known as the "Big Five"⁽⁹⁾. By exploring and incorporating a wider range of sustainable fish and shellfish, we can reduce pressure on these over-exploited species and support biodiversity in our oceans.

Whenever possible, sourcing fish from local, small-scale fisheries can enhance sustainability, as these operations typically have a lower environmental impact and prioritise responsible, community-focused practices. The same principle applies to meat, dairy, fruit and vegetables.  

Buying locally not only supports small farms and strengthens rural economies, but it also reduces food miles, thereby lowering the environmental impact. Local products are also often fresher, higher quality, and minimally processed, offering a clear contrast to mass-produced alternatives.

Sourcing food locally also shifts demand away from large-scale, industrial farming operations, which are responsible for a significant share of the food systems environmental footprint. In contrast, small-scale farmers often employ more sustainable, regenerative practices that work in harmony with nature rather than exploiting it for maximum profit. These practices focus on reducing resource strain and prioritising soil health, an often-overlooked foundation of our ecosystems. Healthy soil is essential for balancing ecosystems, yet it is rapidly degrading under unsustainable farming methods. By choosing foods from farms with a regenerative approach, we help to support soil vitality and contribute to a more resilient, environmentally friendly food system. By making these mindful sourcing choices, we will reduce our environmental impact, aligning with the principles of a sustainable diet.

 

Less Food Waste

Currently the UK throws away 9.5 million tonnes of food waste per year. which equates to around 25 million tonnes of GHG emissions⁽¹⁰⁾. Food waste comes from all stages of the food chain, from agricultural production to the food that is left on your plate after a meal. A significant proportion of this wasted food could be repurposed, either by redistributing it to those in need or by using it in other ways, such as for animal feed or composting. This is also true on an individual, small scale.

Minimal food waste is an essential aspect of a sustainable diet. Not only does it help minimise environmental impact by cutting down on GHG emissions and waste sent to landfills, but it also maximises the use of resources, such as water, energy, and land, that were invested in food production. The United Nations’ Sustainable Development Goals (SDGs) aim to reduce global food loss and waste by 50% by 2030, a critical step to improve food security and nutrition and contribute towards environmental sustainability⁽¹¹⁾.

As individuals, there are several practical actions we can take to reduce food waste. Planning meals ahead, purchasing only what is necessary, and storing food properly to extend its shelf life are effective strategies. Additionally, repurposing leftovers, composting food scraps, and being mindful of portion sizes can significantly reduce waste. Another helpful approach is prioritising local and seasonal produce, which tends to have a smaller environmental footprint, and helps reduce waste related to transportation and spoilage. By incorporating these habits into our daily routines, we can play an important role in creating a more sustainable food system, alleviating the environmental and social impacts of food waste, and contributing to the wider goals of food sustainability.

 

Sustainable Hacks

1. Try a New Plant Each Week

During your weekly shop, try adding a new plant-based food for your meals. From exotic grains like quinoa or teff to new veggies like kohlrabi or seaweed, this keeps your diet exciting and boosts both nutrition and biodiversity.

2. Swap Half Your Mince for Mushrooms or Lentils

If you still want that meat-fix, try replacing up to 50% of mince in dishes like spaghetti Bolognese, burgers, or Shepherd’s pie, with lentils, mushrooms, or other hearty plant-based ingredients. These alternatives are delicious, nutritious, and have a lower environmental impact.

3. DIY Stock from Scraps

Skip the store-bought stock cubes by making your own at home! Collect veggie peelings, meat bones, or seafood shells, and simmer them in seasoned water. Not only does this reduce waste, but it also gives you a rich, tastier base for your dishes.

 

Conclusion

Our current food systems heavily impact the environment, public health, and natural resources, making a collective shift toward a more sustainable diet essential. By choosing more plant-based foods, supporting sustainable sourcing, and actively reducing food waste, we can each help protect our planet, preserve biodiversity, and enhance our own well-being.

According to WWF, if the population adopted a more sustainable diet, it could reduce greenhouse gas emissions by up to 30% and cut agricultural land use by at least 41%⁽¹²⁾ . Such a shift would also significantly lower rates of chronic diseases, including heart disease, type 2 diabetes, and certain cancers.

Together, our individual choices support a healthier planet, a resilient food system, and a sustainable future. The shift may begin with what’s on our plates, but its impact extends far beyond, fostering a better quality of life for ourselves and generations to come.

 

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Sources

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6. WWF & Knorr. (2019). Future 50 Foods. Retrieved from https://www.wwf.org.uk/sites/default/files/2019-02/Knorr_Future_50_Report_FINAL_Online.pdf
7. Willett, W., Rockström, J., Loken, B., et al. (2019). Food in the Anthropocene: the EAT–Lancet Commission on healthy diets from sustainable food systems. Science, 360(6392). https://www.science.org/doi/10.1126/science.aaq0216
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9. Marine Stewardship Council (MSC). Sustainable fish to eat in the UK. Retrieved from https://www.msc.org/uk/what-you-can-do/sustainable-fish-to-eat-in-the-uk#:~:text=The%20%27Big%20Five%27,we%20consume%20in%20the%20UK.
10. Waste and Resources Action Programme (WRAP). Action on food waste. Retrieved from https://www.wrap.ngo/taking-action/food-drink/actions/action-on-food-waste
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