Fresh facts

The BDA Leading on Sustainable Diets

Added on 01/08/2018

By Jo Lewis, BDA & Elphee Medici, Nutrilicious

Introduction
The British Dietetic Association (BDA) is committed to bringing sustainable diets to the top of the dietetic agenda and empower all dietitians with the ideal tools to deliver advice on sustainable eating in their day to day practice.
 
Current eating patterns have become a significant burden to the environment,1 as well as to the health and economy of the nation.2   The need to bring about changes in dietary behaviour has never been more critical for the security of our future generations and the planet.
 
This article provides an overview of the role of sustainable diets and outcomes from recent quantitative and qualitative surveys which will underpin the content of the BDA’s Sustainable diets’ toolkit to drive changes in dietary behaviour.
 
Why focus on sustainable diets?
Sustainable issues are underpinning national dietary guidelines globally,3-8 including the UK’s Eatwell guide.9  The facts are now mounting that our foods choices not only impact on our health but are fast depleting the planet’s resources as well as being a major contributor to greenhouse gas (GHG) emissions.10,11 
 
Our food choices (taking into consideration production, distribution, delivery through to waste):10 
  • Contribute 20-30% of total GHG emissions.
  • Are the leading cause of deforestation, biodiversity loss and soil and water pollution.
  • Account for 70% of all human water use.
  • Are responsible for global inequality: current food production is adequate to meet the needs of the global population of 7 billion, however, 2 billion exceed their needs whilst 800 million suffer hunger.
Additionally, 30–50% of all food produced is spoiled or wasted – representing a waste of land, water and other inputs, ‘unnecessary’ emissions, and contributing to food insecurity.
 
Sustainable diets focus on meeting nutritional needs as well as providing environmental benefits.
Despite a lack of consensus on the exact definition, all experts concur that a sustainable diet should be based on (healthy) plant foods whilst consumption of meat (in particular beef) and dairy produce is reduced but not necessarily eliminated from the diet.12,13  There is also harmonization across existing definitions that a sustainable diet is also one that meets a populations nutritional needs.9,12,13   
 
FAO 2010: “Sustainable Diets are those diets with low environmental impacts which contribute to food and nutrition security and to healthy life for present and future generations. Sustainable diets are protective and respectful of biodiversity and ecosystems, culturally acceptable, accessible, economically fair and affordable; nutritionally adequate, safe and healthy’ while optimizing natural and human resources.”13   
 
Why the focus on reducing meat and dairy?1
  • Livestock production is by far the most significant contributor to GHG emissions (methane, carbon dioxide and nitrous oxide) contributing to 14.5% of all GHG emissions.
    • Ruminant cattle are the main contributors to methane gas emissions, a by-product of their carbohydrate digestion process. Ruminants include cows, pigs, sheep, deer and goats.
  • The high demand for beef and dairy over other ruminants, makes them the highest contributors to GHG emissions. CO2 equivalent emissions from beef and dairy farming are 7½ times greater than chicken and 7 times greater than pig farming. [Gerber 2013]
    • Manure (methane and nitrous oxide).
    • Animal feed production (carbon dioxide).
    • Land-use change (carbon dioxide emissions from land clearing).
  • Cattle consume 40% of all grains produced and over one third of arable land is dedicated to growing grains solely for animal feed production.
  • Livestock is the main cause for deforestation, biodiversity loss, degradation and water pollution.
 
Nutritional adequacy of a plant-based sustainable diet
The Eatwell guide14,15 is just one example of how national dietary guidelines are focusing on environmental as well as nutritional issues.  The Eatwell guide has been modelled to ensure that all macro and micronutrient needs of the population aged 5 years and over are met14 whilst the nation’s carbon footprint is reduced by almost one third.9  As such, the Eatwell guide recommends that 80% of foods we consume should be of plant origin:14    
  • á fruit, vegetables and wholegrain starches.
  • á plant sources of proteins.  For the first time, the UK national guidelines are prioritising plant food sources of protein over animal sources.
  • â meat to 70g per day.  Meat is permitted but at quantities more in line with international recommendations.
  • â dairy intakes by a third.
 
It is well established that diets higher in plant foods and lower in meat and meat products result in lower energy and saturated fat and higher fibre intakes.16-19  As such, it is not surprising that populations following a plant-based diet have significantly lower incidences of non-communicable diseases such as obesity, type 2 diabetes, cancer and heart disease16,17,19 -21 as well as lower mortality rates.19  
 
Micronutrient adequacy of sustainable diets
Well planned sustainable diets,12,13,15 whether based on plant foods only or containing small quantities of red meat and dairy e.g. the Eatwell guide14,15  will meet all essential macro and micronutrients such as iron, calcium and zinc.
 
Intakes of micronutrients amongst populations consuming a predominantly plant-based diet are well within recommendations.16 -18,22  This is despite intakes of some micronutrient in populations following a plant-based diet being lower when compared to those consuming a meat containing diet. The only exception is vegans whose iodine and vitamin B12 intakes tend to be low.     
 
With regard to iron, zinc and selenium specifically (meat being a rich source), individuals following a plant-based diet have adequate intakes and meet national and international recommended intakes.16-18,22  In fact, several population studies have demonstrated higher iron intakes in vegans.16 -18  Additionally, the evidence is mounting that diets high in plant foods and therefore phytates, do not necessarily compromise nutritional status.  It has been suggested that the body adapts to chronic high phytate intakes by increasing absorption and/or retention rates. 22-26 
 
Calcium intakes. Since white flour is fortified with calcium,27 it is not surprising that cereal products (especially bread) contribute similar amounts of calcium to the UK diet as dairy (see table below).28  Furthermore, leading brands of (non-organic) plant-based drink and yogurt alternatives are fortified with calcium to the same level29 and with a similar bioavailability30-32 as calcium present in dairy.  Unlike dairy milk and yogurts, leading brands of non-organic plant-based drinks and yogurts are also a source of vitamin D, thus further assisting with calcium absorption and contributing to bone health.
 
Getting dietitians and the nation on board
With only 1% of the population adhering to the previous, and less plant-based, UK dietary guidelines (the Eatwell plate)33 how can the BDA help to empower dietitians to drive consumers to adopt a more environmentally friendly dietary pattern?
 
The BDA is passionate that dietitians should lead on this critical change and as such has set up the Sustainable Diets sub group within the Public Health Specialist Group to provide direction.   In November 2017, the BDA Policy Statement on Sustainable Diets34 was published with a clear call to action for all dietitians to become involved.  Now, the BDA Sustainable diets’ group with the help of an education grant from Alpro, are working on a toolkit that aims to provide both the scientific knowledge and the practical tools to empower dietitians and consumers to adopt a sustainable eating pattern.
 
Dietitians’ perspective on barriers and motivators to more sustainable eating
Prior to commencing the toolkit, the BDA reached out to its members to gain further insight with regard to resources needed to help overcome barriers to and amplify motivators for sustainable dietary behaviour change.
 
Top barriers and motivators
  1. Lack of practical / “how to” knowledge and resources – to overcome this will be a key driver for both consumers and dietitians.
    • Currently, sustainable eating is not on the UK dietetic or school curriculum.
    • Essential consumer skills such as cooking, menu planning and budgeting are lacking.
  2. Perceptions that sustainable healthy eating requires more time, more money and taste has to be compromised.
  3. The food environment.  The imbalance of healthy and affordable plant-foods to unhealthy, and predominantly animal-based, food availability from retailers, restaurants, take-aways etc.
  4. Language used when communicating to consumers: this should be tailored to the target audience e.g. taking into consideration culture, age groups, socio-economic and education status.
  5. Clarity over contradictory messages between sustainable and healthy eating advice:
    • Fish.  The UK dietary recommendation to double current intakes of fish to 2 140g servings a week is clearly at odds with sustainable issues of over-fishing.  The drive behind the fish dietary recommendations is partly for healthier sources of protein but also to help improve intakes of long chain omega-3 fats for heart health benefits.  Yet, the evidence is clear that individuals following vegetarian and vegan diets (devoid of long-chain omega-3s) have significantly lower incidence of heart disease? Additionally, the recent July publication by Cochrane has challenged the association between long-chain omega-3 fatty acids and cardiovascular benefits.35  So should our fish dietary recommendations be challenged?
    • Processed foods.  Most definitions of sustainable diets recommend avoidance of all processed foods.  This is contrary to healthy eating advice across all socio-economic groups; processed foods such as tinned and frozen fruit, vegetables, beans and pulses are affordable and convenient ways of improving the health credentials of a diet and overcoming two key barriers to dietary change – cost and time constraints.
  6. Misconceptions
    • Sustainable diets automatically associated with vegan and vegetarian diets only.
    • Nutritional inadequacy.
As part of the BDA toolkit, a comprehensive scientific review of the literature is currently underway to inform and provide dietitians with the confidence to overcome such misconceptions.  As mentioned earlier, there is no reason why sustainable diets cannot include some meat and dairy and nutritional inadequacies are usually associated with specific sub-groups of the population rather than plant-based eating per se.  E.g. vitamin drops containing vitamins A, C and D for all children up to the age of 5,36 folic acid supplements for the first 12 weeks of pregnancy,37 and vitamin B12 supplements for those following a vegan diet.38

The ideal BDA toolkit should:
  • Use visuals wherever possible e.g. infographics.
  • Use simple, clear and unambiguous messaging.
  • Be of a multi-organisation approach to bring on board all food service sectors to help ensure that a sustainable and healthy food environment is affordable and readily accessible for all consumers.
  • Have a single, trusted point of access for all material: e.g. the BDA website.
  • Provide teaching materials / aids for dietetic training and schools.
  • Provide practical and realistic advice that will resonate with different population groups and cultures.
 
The focus of advice to overcome key barriers to change
  • Reduce mixed messaging by using the Eatwell guide which consumers can resonate with.
  • Highlight reasons to believe / added benefits for individuals e.g. nutritional and health benefits that can be gained by adopting plant-based eating such as calorie savings, cost savings etc.
  • Iterations that sustainable diets do not have to mean complete avoidance of meat and dairy.
  • Overcome the lack of practical skills and know-how by providing:
    • Everyday meal swaps for different population groups and cultures.
    • Simple quick recipes.
    • Local cooking sessions and placing cookery on the school curriculum.
    • Menu, cost/budgeting planners: demonstrating that sustainable diets are cost effective by providing weekly / monthly meal plans to accommodate different budgets.
    • Tips for sub-population groups at risk of micronutrient deficiencies: e.g. under 5’s, pregnant women, elderly etc.
      • Plant food options for specific micronutrients of concern e.g. iron, calcium, iodine.
    • Out of home and convenience / ready meal advice.
    • Improved animal welfare was a key consumer motivator for many dietitians.
    • Waste: tips on how to reduce waste through meal planning, using all parts of plants and animals etc.
    • Seasonality: top tips on how to source seasonal produce.
    • Local produce. How to source economical local produce, get involved with initiatives.
 
Using these insights, the BDA is now working towards formulating the first stages of the toolkit, which should be ready in the last quarter of this year.
 
The BDA would like to acknowledge the support from one of its corporate partners Alpro and its science and nutrition team whose vision is of a world where more of what we eat comes directly from plants. 

References
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