Expressly written for StreetCube by :-
Louise Symington MSc BSc (Registered Dietitian)
The Sustainable Dietitian

Nutrition can be defined as the process of eating all the necessary food for health and growth. All food contains nutrients which are molecules used in the body to sustain life. The six major nutrients are: carbohydrates, fats, proteins, vitamins, minerals and water.

In the context of ‘health education’, food is catagorised into 5 major groups; protein, complex carbohydrates, fruit and vegetables, dairy and dairy alternatives and fats. The Eatwell Guide has been developed by Public Health England (PHE) to visually represent the proportions of these groups we should be eating (4). Snack foods and water have a category outside of the ‘pie chart’.


The foundations of a nutritionally balanced diet means that we should be eating a high proportion of fruit and vegetables and complex carbohydrate foods with moderate amounts of meat, dairy and protein alternatives with a relatively small intake of fats and sugars.

When it comes to meals, the way we cook and flavour the food increases the nutritional quality. Relying less on salt and using a variety of herbs and spices enables food to be more potent in its health giving effects. In recent years there's been a real surge in chefs making tasty, nutritious meals which challenges the myth that healthy meals are just ‘rabbit food’ !

How we eat has a huge impact on our physical condition. If we don’t consume the right proportion of key food groups or meet our ideal calorie intake then it will lead to ‘under’ or ‘over’ nutrition.

Under-nutrition means that we are not getting enough energy and nutrients. This can lead to deficiencies, weight loss and associated medical problems such as anaemia or osteoporosis. Causes of undernutrition could include eating disorders, a pre-existing medical condition or simply not being able to afford healthy food. Over- nutrition is major public health concern. Excess calories is linked to obesity which in turn is risk factor for many long term diseases such as diabetes, many cancers and cardiovascular disease. In 2016, NHS data showed that 26% of adults were classified as obese, a 15% increase since 1993! (5)

Results from the National Diet and Nutrition Survey (NDNS) 2016/17 (6) shows that as a nation, we aren’t following the Eatwell guidelines. The UK population is eating far too much fat, sugar and protein with too few complex carbohydrates. Furthermore, our fruit and vegetable consumption is too low. Fruit and vegetables help balance energy intake as they are physically filling but low in calories. Only 26 per cent of adults and only 16 percent of children consume the recommended 5 or more portions of fruit and vegetables a day which is far too low. (5)

Why are we not eating as healthily as we should? There could be many reasons; social and economical factors, junk food advertising and the food environment all play a part.

A healthy, sustainable diet can be underpinned by the 4 characteristics of the environment, social factors, ethics and health.
From an environmental perspective, what is good for the planet can be good for our health.

Research shows us that very high fat and high protein diets (especially red and processed meat) can lead to a variety of long term health conditions such as diabetes, cardiovascular disease and obesity. Generally speaking, animal proteins have a higher environmental footprint than plant foods (such as legumes and fruit/veg). So if we can reduce meat and dairy intakes and increase plant foods it’s a win - win situation. (2) The key message is that animal proteins are replaced with a variety of good quality plant based proteins (beans, peas, legumes etc) for optimal health rather than simply cutting out animal protein completely. (7)

From an ethical perspective, the treatment of animals needs to be considered with respect to production and welfare standards. Sometimes this may also align with health benefits. For example, grass fed beef has a healthier fat profile than grain fed, intensively reared beef. However, a ‘trade-off’ is that animals which are ‘slow reared’ produce more methane and use more resources over their lifetime. Despite this, the overarching message is to eat less animal protein overall and choose ‘better’ where possible. (1)

In terms of social factors social factors, a sustainable diet would mean sourcing ingredients where companies abide by fair trade or fair pay standards, follow anti slavery policy and other such measures.

There are many definitions of sustainable diets from charities and NGOs. However, the British Dietetic Association (BDA) are an authoritative source of healthy and environmentally sustainable dietary guidelines. The BDA’s publication, One Blue Dot (3) supports the UK Eatwell Plate. The guidelines are as follows;

  • 1. Reduce red meat less than 70g/per person per day or less than 350g-500g per person per week (cooked weight). To cut down on all processed meat such as burgers and bacon.
  • 2. To prioritise plant proteins such as beans and lentils, soya (beans, mince, nuts, tofu), mycoprotein (QuornTM), nuts and seeds.
  • 3. To choose seafood from sustainable sources and follow oily fish recommendations (see PHE Eatwell guide)
  • 4. Moderate dairy consumption. Use fortified plant-based alternatives where needed.
  • 5. Base meals on potatoes, bread, pasta, rice and other starchy carbohydrate foods. Use whole grain varieties of foods and tubers such as potatoes.
  • 6. Use seasonal + locally produced vegetables/fruit or tinned/frozen. Air freighted, pre-packed and prepared fruit and vegetables.
  • 7. Reduce portions of animal and dairy foods and high fat, high sugar and high salt foods.
  • 8. Choose tap water and tea or coffee over soft drinks.
  • The key issue to remember is that there are no ‘good or bad’ foods. It’s simply the proportions we consume in our diet that needs improving. Thinking about what we CAN eat rather than what we CAN’T is the most effective mindset when adopting a healthy and sustainable way of eating.