Do you want to contribute to better health for ourselves and our planet but don’t know where to start? Scientists are advising that we all shift to a plant-rich diet to achieve a sustainable future, but this can seem a daunting prospect. In this 4th post in the Yogurt in Nutrition Initiative series on sustainable diets, we look at the evidence supporting the types of diets, such as flexitarianism, that could help provide the solution.

What is flexitarism ? What is a flexitarian diet?

Flexitarian diets range from omnivore diets with reduced amounts of meat – e.g. through reduced portion sizes or having meat-free days – to diets that are mainly vegetarian but include meat occasionally. Flexitarian diets are generally plant-rich, containing fruits, vegetables, grain, legumes, nuts and seeds, and include modest amounts of meat and varying amounts of fish and dairy foods.

A flexitarian diet encourages variety rather than restriction as you don’t have to exclude any specific food. So it’s different from a vegetarian diet, which excludes all meat, fish and poultry, and from a vegan diet which eliminates all animal products including eggs, dairy products and honey. Several variations of the vegetarian diet also exist, such as the pesco-vegetarian or pescatarian, which adds fish and seafood to the diet, and lacto-vegetarian which includes dairy products as well as plant-based foods.

As flexitarian diets don’t completely eliminate meat and still maintain dairy food intake, they are a favourite among people who want to lead a healthier, more sustainable lifestyle but find vegetarianism too restrictive.

That’s why flexitarianism is becoming increasingly popular across the world, the trend being driven initially in the USA and Australia with the aim of managing body weight.^1,2 More recently, people’s motivation to move towards flexitarianism is more to do with global health and environmental concerns.

“A flexitarian diet is largely plant-based but can optionally include modest amounts of fish, meat and dairy foods.” – EAT-Lancet 2019³

Why might you choose a flexitarian diet?

Scientists view the flexitarian diet as a flagship of sustainable diets for people all over the world.^3,4

That’s because research shows that we need to shift to more plant-based diets globally, both for our own good and for the good of the planet. Especially in affluent countries, people need to eat less meat to relieve pressure on the environment while meeting nutritional and health demands.

But many people feel that switching to a vegetarian or vegan diet doesn’t fit with their lifestyle. If you’re used to your regular Sunday roast or to a summer’s evening BBQ, it can seem like too big a step to take.

A flexitarian diet can provide a practical solution. For most people, it’s realistic way to achieve the aim of significantly reducing the amount of animal-source foods in the diet. At the same time, a flexitarian diet gives you the freedom to choose a wider variety of foods than vegetarian or vegan diets.

So it’s a win-win situation – you still get to tuck into your favourite meals, albeit less meat-heavy than in the past, knowing that the environment is better off too!

A flexitarian diet is all about eating better and healthier, high-quality foods, that have been produced under conditions more respectful of the environment – and preferably locally-sourced.

Conducting studies on the flexitarian diet, the World Wide Fund for Nature (WWF) concluded that the flexitarian diet offers a balance that allows families to:⁵

• eat more healthily
• eat quality products while protecting the environment
• cut the carbon footprint from their food
• reduce pressure on land and marine resources

What does a flexitarian dish look like?

Becoming a flexitarian means moving towards a diet that’s rich in fruits and vegetables, legumes, whole grains, nuts and seeds, but low in sugar and meat.⁶ You’ll continue to include dairy products in your diet as they’re a great source of several important nutrients, but their impact on the environment is much less than that of beef meat; in fact, 5- to 6-times less per g protein.⁷

But it’s not all about what’s good for you. For a diet to be sustainable, we have to enjoy our food – a flexitarian diet means you don’t have to give up the pleasure of eating some of the foods you enjoy.

What are the nutritional advantages of a flexitarian diet?

Nutritionally, the flexitarian diet is likely to hold some advantages over vegan and vegetarian diets, as well as over the current typical diet of most westernised countries.

Because humans have evolved as omnivores, vegans and vegetarians need to compensate for the nutrients that they’d otherwise get through eating animal products. If they fail to do so, they risk developing nutritional deficiencies and health problems.

This applies especially for groups with specific nutritional needs – teenagers, pregnant women, the elderly or people with a specific chronic disease.

These groups may need to take specific supplements to make up for the shortfall in the diet. Vegan diets in particular may lead to deficiencies in vitamin B2 and B12 which are provided naturally only by animal products, iron and zinc which are present particularly in meat, or calcium and iodine which come largely from dairy products.

In a flexitarian diet, the large amount of plant-based foods balanced with a significant intake of dairy products and low amount of meat generally provides an all-round healthy mix of high-quality protein, fibre, vitamins, minerals and healthy fatty acids.

What does a flexitarian diet mean for your health?

The healthy mix of nutrients in the flexitarian diet spells good news for our health, studies suggesting benefits for weight control and blood pressure, and reduced risk of type 2 diabetes compared with the typical non-vegetarian diet.⁸

The flexitarian diet recognises that, while meat provides valuable protein and nutrients, eating too much red meat and particularly processed meat over the long term may increase the risk of heart disease, stroke, and certain forms of cancer such as colon cancer.⁸

A global modelling study of diets that were in line with available evidence on healthy eating found that adopting a flexitarian diet is associated with a sharp fall in premature death – the reduction was 19% for the flexitarian diet and 22% for the vegan diet.⁶ The reduction in early deaths reflected less heart disease, stroke, and type 2 diabetes. In this analysis, the flexitarian diet was defined to reflect the dietary recommendations for healthy and more plant-based diets. It excluded processed meat but included:

• up to one serving of red meat per week (14 grams/day on average),
• a moderate amount of poultry (up to half a serving/day or 29 g/d), fish (at least a half serving/day or 28 g/d) and dairy foods (up to one serving/day or 250 g/d)
• generous amounts of fruit (at least 2-3 servings/day or 200 g/d), vegetables (3-4 servings/day or 300 g/d), nuts and seeds (2 servings/day or 50 g/d), and legumes (half a serving/day or 50 g/d). Grains, wheat, rice or maize should provide up to 860 kcals per day for energy balance.⁶

What impact would a flexitarian food system have on the environment?

Latest studies suggest that switching to flexitarian diets could shrink our carbon footprint and help to put us on course for reaching the goals set for 2050 by the Paris climate Agreement, to which 195 countries signed up in 2016.⁹

In the first of two studies carried out by the WWF to develop healthy and sustainable diets, a flexitarian diet was modelled in the UK, adapted for adolescents, adults and elderly people.⁴

The researchers designed the diets assuming that food consumption and food production should contribute equally to the reduction we need to make in greenhouse gas emissions in our food system. The diets would make a major contribution to reaching the targets set for the UK by the Paris Agreement, while still meeting the nutritional needs of the different groups studied.

In this model, the composition of the flexitarian diet was kept as close as possible to the average UK diet for each group, but with much less meat, particularly beef and lamb. The diet also contained less cheese, but other dairy – one of the most important sources of iodine in the UK diet – remained similar to current consumption. Legumes, nuts, vegetables and oilseeds were all increased in the diet.

In a second study, the WWF modelled a flexitarian diet for the French population.⁵ Compared with the current average French diet, the flexitarian diet had a 66% reduction in the amount of beef and veal eaten and a 69% reduction in industrially-processed foods containing fats, salt and sugars. It also cut down on wild-caught fish and on foods made from refined flour. In their place were wholegrain flours, more vegetables, cereals and legumes. Meanwhile, consumption of dairy products remained the same as in the current average French diet.

The researchers carried out their analysis for a family of four – two adults, a teenager and a child aged under 10 years. They found that the flexitarian diet made it possible to reduce the family’s greenhouse gas emissions by 38% while fully covering their nutritional needs.

Will a flexitarian diet increase your shopping bill?

The good news is that a flexitarian diet allows you to eat more healthily and help protect the planet – all without adding to your weekly shopping bill.

A Swiss study modelling nine alternative diets including current, vegetarian and flexitarian diets, found that healthy and nutritious diets in which we cut down on meat, can come hand-in-hand with environmental sustainability goals, without putting extra strain on our purse.¹⁰ That’s because plant-based foods such as legumes, nuts and seeds tend to be cheaper than the meat they are replacing.

In the WWF model of a sustainable diet for France, the composition of the flexitarian diet resulted in a 19% saving in the daily food budget for an adult and a 21% reduction in the average cost of a weekly food shop for a family of four, compared with the current diet.⁵

The cost savings made with the flexitarian diet would make it possible to introduce around 50% of organic and other certified products into our food shopping for almost the same amount of money as for the current diet, the researchers calculated. In other words, this flexitarian diet in which about half the foods are organic, would cost a family 190 Euros per week, compared with the current weekly food shop of 187 Euros.

In the UK, the WWF’s flexitarian diet models was associated with a small cost increase compared with the current diet, mainly due to the increased amounts of fish and vegetables.⁴ But the WWF points out that food prices are set to rise in coming years, with the higher increases being seen for foods based on animal feed rather than the foods that dominate the flexitarian diet.

So the chances are the flexitarian diet will offer us an option that costs us less, has a lower environmental impact and a better overall nutritional quality than the diet most of us eat now.

“It’s indeed possible to eat a sustainable, nutritious diet that contributes to the future health of the planet and its population, without significant increases in costs.” – WWF (UK), 2017⁴

Find out more:   

• Find out why we need to shift to sustainable diets 
• What would a more sustainable diet mean for you?

Sources:

1. World Business Council for Sustainable Development. FRESH Insight Report: Consumption behaviour and trends: understanding the shift required towards healthy, sustainable and enjoyable diets. 2018.
2. Forestell CA. Flexitarian diet and weight control: healthy or risky eating behaviour? Frontiers in Nutrition. 2018;5:article 59.
3. Willett W, Rockström J, Loken B, et al. EAT-Lancet Commission Summary report: Food in the anthropocene: the EAT–Lancet Commission on healthy diets from sustainable food systems. Lancet. 2019;393(10170):447-492.
4. WWF (UK). Eating for two degrees. 2017.
5. WWF France. Towards a low carbon, healthy and affordable diet. 2018.
6. Springmann M, Wiebe K, Mason-D’Croz D, et al. Health and nutritional aspects of sustainable diet strategies and their association with environmental impacts: The Lancet Planetary Health. 2018.
7. Poore J, Nemecek T. Reducing food’s environmental impacts through producers and consumers. Science. 2018;360:987–992.
8. Derbyshire EJ. Flexitarian diets and health: a review of the evidence-based literature. 2018.
9. United Nations Treaty Collection. The Paris Agreement 2016. Archived from the original on 21 August 2016.
10. Chen C, Chaudhary A, Mathys A. Dietary change scenarios and implications for environmental, nutrition, human health and economic dimensions of food sustainability. Nutrients. 2019 Apr 16;11(4).

Join us in exploring the scientific discoveries that are supporting our shift towards a sustainable diet for all. In this third post of the Yogurt in Nutrition Initiative series, we focus on the world of food production and the steps being taken to transform it to provide for our growing global population – in a way that protects both our health and our environment.

Feeding the world’s growing population will require widespread changes in the way we produce our food, especially in the face of mounting pressure from climate change.

Recognition of this need is providing the stimulus for ground-breaking research, paving the way to a transformation in food production that will not only feed the world’s growing population, but will also give us a vital opportunity to boost human health.

At the same time, new approaches to sustainable food production system must set us firmly on track for meeting the goals of the 2015 Paris Agreement to curb climate change, by limiting global warming to well below 2^oC above pre-industrial levels and to restrict the increase to 1.5°C.

To achieve this climate target, our world’s agriculture needs to switch from a major greenhouse gas producer to one that captures greenhouse gasses by acting as a sink for carbon emissions – in the same way as our forests relieve pressure on the environment by trapping and locking in carbon dioxide.

Our food system should also achieve the urgent transformation needed to conserve and use nature sustainably – halting the alarming decline in global biodiversity that has a profound impact on people around the world, as highlighted by a landmark international report released in 2019.¹

With these goals in mind, scientists are testing efficient and eco-friendly agriculture that reduces the burden on our limited land and water resources while meeting our growing nutritional and health needs. They’ve made some important inroads into finding the best way forwards.

‘Agriculture faces a massive dual challenge in feeding a growing and increasingly affluent global population, while at the same time reducing its negative environmental impacts.’ – Karlsson et al, 2018²

What are the challenges that need to be overcome in food production?

The big challenge is to balance the increasing demands of nutritional and health needs for the 10 billion people predicted to live on Earth by 2050 with the current negative environmental impact of our food production.

Agriculture can disturb the environment as it expands into other ecosystems, destroying natural habitats of wild species with harmful effects on biodiversity, degradation of soils and reduced stored carbon – when forests are cleared and burned, for example. As agriculture intensifies, it increases the use of energy, water and chemicals such as fertilisers, pesticides, and herbicides, leading to water depletion and pollution.³

As a result of such human activities, over a million animal and plant species are threatened with extinction, many within the next few decades – the fastest rate throughout human history.¹ Such species make up the ecosystems on which populations around the world depend for their food and living.

What needs to change in order to achieve more sustainable food production?

The main direction for changes needed to improve the environmental footprint of our food production are summarised by the EAT-Lancet Commission along with the intergovernmental body on biodiversity and ecosystems, and other recent scientific studies aimed at identifying healthy diets and sustainable food production.^1,4

As an example, EAT-Lancet considers that our food production should:⁴

• use no more land than it does currently
• safeguard existing biodiversity
• reduce water use and manage water responsibly
• substantially reduce nitrogen and phosphorus pollution (coming from fertiliser use)
• produce zero carbon dioxide emissions
• cause no further increase in methane and nitrous oxide emissions.

A key step will be to feed the world’s population on only existing agricultural land, the EAT-Lancet Commission recommends. This means stopping the expansion of agricultural land so that it doesn’t encroach further on forests and other natural ecosystems. Along with limiting use of pesticides, preserving these natural environments is crucial to maintaining our planet’s plummeting biodiversity.¹

Oceans should also be managed to ensure that there’ll be enough fish in the sea to feed our future generations, says EAT-Lancet.⁴

Agriculture needs to use the land more efficiently, with improved use of fertilisers and water. Currently, according to the World Wide Fund for Nature (WWF), as much as 70% of all fresh water withdrawn from the ground is used for agricultural irrigation, which often has a major impact on water availability and quality.⁵

The report from the intergovernmental body on biodiversity recommends an integrated approach to solving the problems, preserving ecosystems and allowing us to use nature sustainably.¹ Conservation programmes, protection of watersheds, and incentives and sanctions to reduce pollution are among the measures needed to promote better agricultural practices and use of resources. Local communities and indigenous people have a key role to play in such measures, says the report.

Nearly one-third of food produced currently goes to waste. EAT-Lancet also recommends at least halving food losses – this will require major changes in food storage, transport, processing and packaging (especially in low-income countries), as well as informing consumers, food retailers and restaurant owners on how to reduce their food waste (especially in higher-income countries).⁴

How do we balance the environmental impact of the food we produce with its nutritional benefits?

For a food system to be sustainable, it must take account of the combination of nutritional, health, socioeconomic and environmental impacts – four closely linked dimensions.

EAT-Lancet recommends shifting agricultural priorities so that we produce not only enough calories to cope with our growing population but enough diversity of high-quality foods to provide us with a healthy nutrition. We’ll need a variety of nutritious foods rather than large amounts of just a few crops.⁴

‘Agriculture and fisheries must not only produce enough calories to feed a growing global population but must also produce a diversity of foods that nurture human health and support environmental sustainability.’ – EAT-Lancet, 2019⁴

The EAT-Lancet recommendations raise dilemmas and controversies, particularly regarding livestock farming. Meat especially is associated with high greenhouse gas emissions and the use of large quantities of land, water and fertilisers. It’s not just because of the animals themselves but also because of the feed they need. In Europe, for example, 58% of available cereals and 67% of oilseed/protein crops are used to feed livestock.⁶

But many people around the world, especially small-holder farmers in low-income countries, depend on livestock for their livelihoods and as a vital supply of nutrients which they may otherwise find hard to get from their diet.

Dairy production in particular is seen as a powerful tool to reduce rural poverty, especially in low-income countries.⁷ By retaining dairy cows, populations around the world can benefit from the nutrient-rich content of dairy products and so find it easier to meet their nutritional needs than if they were growing plant-based foods alone.

Clearly, livestock production should be considered according to specific contexts. Studies have suggested that livestock, produced in a sustainable way and consumed in reasonable quantities, can provide nutritional, ecological, and economic benefits. Sustainable livestock production can be achieved by using pasture-land that couldn’t be used for growing crops, and by feeding the cows on crop left-over yields, the studies suggest (see below).

How might sustainable agriculture work in practice?

The EAT-Lancet report provides global recommendations to steer us towards sustainable food production. However, in practice, studies suggest that the sustainable answer to food production is likely to differ from region to region, reflecting local climate, geography, culture, and economies.

Scientists are exploring the options, developing regenerative agriculture models that preserve and renew our resources while providing reliable and safe access to healthy foods for all. Their aim is to pave the way for policy-makers and scientists to make informed decisions about guiding agriculture for the future.

Among these pioneering studies is a project called Ten Years for Agroecology in Europe (TYFA).⁶ It has modelled a possible option for an eco-friendly agricultural scenario for Europe in 2050 and compared it with today’s European food system.

The TYFA scenario abandons pesticides and synthetic fertilisers, stops massive imports of animal feed (such as soya), redeploys natural grasslands and extends the use of hedges, trees, and ponds. At the same time, the model assumes that people adopt healthy diets with fewer animal products and more fruit and vegetables. It allows a large capacity for grazing livestock, but limited pork and poultry, which are mainly fed with imported feed. Hence the TYFA diet still contains about 100 g/day of meat and an equivalent of 300 g/day of milk as dairy products.

This kind of ecological agriculture tends to be less productive than current farming methods in Europe and so is usually considered incompatible with producing enough food for the population while also tackling climate change.

But the model showed that, despite a 35% fall in production compared with 2010, this envisioned scenario would:

• meet food requirements for Europeans, while still keeping up capacity to export cereals, dairy products and wine
• cut agricultural greenhouse gas emissions by 45%
• help to restore biodiversity and to protect natural resources.

Another study has modelled a sustainable food system scenario for Norway, Sweden, Denmark and Finland.² Issued from a consultative process involving five local environmental non-governmental organisations (NGOs), the Future Food Vision for the Nordics is based on organic farming and local food production. To limit direct competition between animal feed and food for people, livestock are fed only from ‘left-over streams,’ – by-products from food production, pastures and perennial grass/clover mixtures.

In the model, consumption of meat, especially non-ruminant meat, is reduced by 81% compared with current consumption in the Nordic countries, but consumption of dairy products remains about the same as it is currently. The researchers estimated that 37 million people could be supplied using this agricultural scenario – much more than the current population of 26 million people. It would cause greenhouse gas emissions of only 0.48 tCO₂e (tonnes of carbon dioxide equivalent – a measure allowing comparison of the emissions of other greenhouse gases relative to one unit of carbon dioxide) per diet per year.

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Find out more:

• What is a sustainable diet, why do we need it?
• What would a more sustainable diet mean for you?
• What is a flexitarian diet ?

Sources:

1. Diaz S, Settele J, Brondizio E, et al. Summary for policymakers of the global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. 2019. Unedited advance version
2. Karlsson JO, Carlsson G & Lindberg M, et al. Designing a future food vision for the Nordics through a participatory modeling approach. Agronomy for Sustainable Development. 2018;38:59.
3. Foley JA, Ramankutty N, Brauman KA, et al. Solutions for a cultivated planet. Nature. 2011;478(7369):337-42.
4. Willett W, Rockström J, Loken B, et al. EAT-Lancet Commission Summary report: Food in the anthropocene: the EAT–Lancet Commission on healthy diets from sustainable food systems. Lancet. 2019;393(10170):447-492. 
5. WWF (UK). Eating for two degrees. 2017.
6. Poux X, Aubert PM: IDDRI. An agroecological Europe: a desirable, credible option to address food and environmental challenges. 2018.
7. Food and Agriculture Organization of the United Nations. Dairy development’s impact on poverty reduction. 2018.