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Food Sustainability & Waste Evidence for change
Prepared by: Zachery Rayson, MSc, ANutr
November 2015
1
Contents
Background 2
Terms of Reference 2
Food and Sustainability 3
Influence of Food/Food Groups 3
Influence of Food Production 5
Influence of Governance and Food Miles 5
Food Waste and Sustainability 7
Food Waste in the Food Service Industry 8
Food Waste in Hospitals 8
Sources of Food Waste 9
Influence on Climate 9
Measures to Reduce Food Waste 10
Overall Summary of Evidence and Suggested Actions 13
Suggested Actions to Take 14
References 15
2
BACKGROUND:
The UK has a target for climate change to reduce greenhouse gas emissions to 80% below 1990
levels by 2050. Achieving such targets requires a multifactorial approach. Coincidentally, the
challenges associated with food and sustainability have gained increasing importance and, although
the recent Hospital Food Standards Panel report limits recognition to food waste, it’s recognised
that the global food system makes a significant contribution to climate change.
Clean air and water, healthy soils, the presence of a diverse range of other living species and a
climate to which we are adapted, collectively constitute our life-support system. However, numerous
studies have shown that the food supply chain is jeopardising their functioning: it is a major cause of
greenhouse gas (GHG) emissions, unsustainable water extraction and pollution, deforestation and
biodiversity loss. All these effects have major, and negative, consequences for human well-being.
It is the role of policy makers and associated professionals to facilitate the provision of a sustainable
diet: “those diets with low environmental impacts which contribute to food and nutrition security and
to a 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 optimising natural and human resources”.1
TERMS OF REFERENCE:
The importance of food in hospitals for patients, staff, visitors, and for sustainability, was recognised
in the Department of Health’s Hospital Food Standards Panel report (2014). This report asked that
all NHS Trusts develop and maintain a Food and Drink Strategy. To achieve this, in supporting the
Nutrition and Hydration Steering Group at the East Lancashire Hospitals NHS Trust, a review to
assess current/recent literature (primarily limited to publication within the last 5 years) has been
performed on the following:
The evidence for a role of food in relation to sustainability.
The evidence on food waste and sustainability.
3
FOOD AND SUSTAINABILITY:
The challenges relating to food and sustainability are multifaceted. Estimates find that the food
system as a whole contributes between 15 and 28% to overall GHG emissions in developed
countries, with all stages in the supply chain, from agricultural production through processing,
distribution, retailing, home food preparation and waste, playing a part.2
Agricultural production makes the single greatest contribution to overall impacts, accounting for
nearly half of food-related GHG emissions in developed countries. While the direct impacts of
farming (from methane [CH4] and nitrous oxide [N2O] emissions) contribute around 10-12% of global
emissions, there are also indirect impacts to consider. Agriculturally induced deforestation causes
the release of CO2 into the atmosphere, and taking this into account adds a further 6-17% to
agriculture’s share of the burden. Once all direct and indirect impacts are summed, agriculture’s
contribution to the global emissions total has been estimated to account for as much as 30%.2
In addition to CO2 release, agriculturally induced deforestation is the main cause of biodiversity loss
worldwide. It is also responsible for 70-80% of all human water withdrawals (water scarcity is
becoming more widespread in many parts of the world) and is a significant cause of water pollution.
The use of fertilisers, manure and nitrogen-fixing legumes have disrupted global nitrogen and
phosphate cycles, with negative impacts on water quality, aquatic ecosystems and marine
fisheries.2
INFLUENCE OF FOODS/FOOD GROUPS:
Within the food sector, livestock production is the most damaging process to the environment, both
in terms of GHG emissions and other environmental burdens.3,4,5 Global estimates suggest that
livestock production accounts for about 12-18% of global GHG emissions and about half of the food
system’s total impacts, more when land use change impacts are included. The sector uses 70% of
agricultural land overall and a third of arable land and as such plays a leading role in CO2 release
and biodiversity loss from deforestation. Livestock are also the greatest source of water pollution in
the agricultural sector and a major user of finite irrigation water.2,6
Numerous assessments of individual food products find that meat and dairy products carry a
disproportionately high environmental burden1. The difference between GHG emissions for animal-
based foods versus plant-based foods can be large,6,7,8 e.g. ruminant meats have emissions per
gram of protein about 250 times those of legumes. Furthermore, eggs, dairy, non-trawling seafood,
tradition (non-recirculating) aquaculture, poultry and pork all have much lower emissions per gram
of protein than ruminant meats.9
This relationship is partly exemplified by the ‘Double Pyramid Model’ (figure 1). This model shows
that the foods offering the greatest benefits from a nutritional viewpoint (such as vegetables, grains,
pulses, and fruit) are those with the lowest environmental impact, while the foods that should be
consumed in moderation for health reasons, such as red and processed meats, are those with the
highest impact e.g. the carbon footprint of fruit and vegetables are 55 and 32 times lower,
respectively, than the carbon footprint of red meat.10
4
The relation between food/food groups and sustainability aligns with the perspective – highlighted
within recent literature – of demand restraint.2 Central to this perspective lies the conviction that
excessive consumption, particularly of high-impact foods such as meat and dairy products, is a
leading cause of the environmental crisis we face. It’s suggested that if consumption is not curbed
globally, then given current dietary trends in demand, agricultural emissions are set to rise even
when a broad range of production-side mitigation measures are deployed. Livestock sector growth
could push the planet to the point where humanity’s biological existence is threatened with it
suggested that per capita meat consumption in 2050 may need to be between 20 and 40% of what
it is today.2
Demand restraint coincides with research finding that reduced consumption of livestock products
would benefit health, i.e. modelled studies suggest that public health and environmental
sustainability goals for the food system converge under scenarios such as reduced meat
consumption.3,4,7,11
There is growing evidence of a link between high consumption of meat and poor health outcomes.
This may be because of high saturated fat content in animal products, high salt levels in processed
meat or high consumption of meat limiting the consumption of fruit, vegetables and cereals, which
have health-promoting properties.3 Today’s agricultural system has increased access for many to
energy- and fat-dense foods. Such high-impact foods are suggested to influence obesity, which also
carries an environmental cost: studies conclude that a reduction in obesity could yield
environmental benefits through reduced food production (especially livestock) as a result of less
consumption, reduced passenger weight decreasing the amount of energy required to fuel vehicles
and less food waste.2
Optimised sustainable diets emphasise a reduction in high-impact foods, suggesting that the diet
needs to shift away from meat and high fat and/or sweet foods and toward fruit and vegetables and
starchy foods (e.g. bread, pasta, rice and potatoes) to meet both dietary recommendations and
reductions in GHG emissions. One specific example modelled a diet providing enough meat for
around 4 main meals per week if used in quantities that matched current typical meals in the United
Kingdom, with GHG emissions of the diet estimated to be 2.43 kg CO2-eq/d (a reduction of 36%
Figure 1: The double food and environment pyramid
5
from the 1990 baseline). This diet amounts to a suggested 60% of the current intake of all meat and
48% of the intake of red meat in the United Kingdom and a diversion towards dairy products lower
in fat. Indeed, a reduction in the intake of animal products carries risk – particularly a decrease in
the intake of essential minerals.12 However, there are studies showing that plant-based diets can
supply an adequate balance of key nutrients at a lower GHG ‘cost’ than meat-dominated diets.2
Optimised models of course can be impractical. The Dietary Approaches to Stop Hypertension
(DASH) dietary pattern – high in dietary compounds such as whole grains, fruits and vegetables,
low-fat dairy products, dietary fibre, n-3 fatty acids, magnesium and calcium13 – presents a negative,
monotonic association with GHG impact based on the level of accordance with guidelines.
Furthermore, this diet is found to reduce weight gain, lower the incidence of stroke, heart failure,
and fatal cardiovascular disease and is associated with reduced risk of type 2 diabetes and
colorectal cancer.14
INFLUENCE OF FOOD PRODUCTION:
The need to address impacts by developing farming and post-harvest supply chain approaches that
cause less damage is exclaimed via a perspective of improve efficiency. This perspective proposes
that both environmental and health concerns associated with meat and dairy products can be
addressed through technological means. Breeding, feeding and housing strategies, together with
research into ways of inhibiting methane emissions from ruminant livestock, can reduce the per unit
environmental footprint of meat and dairy production. Whereas providing consumers with meat that
is leaner and dairy products lower in fat (through animal breeding and feeding strategies or by
removing fat post production) may alleviate health concerns.2
The amount of food actually delivered (0.7 PgCyr-1
), compared with overall cropland productivity
(8.3 PgCyr-1
) or compared to harvest (2.4 PgCyr-1
) is extremely small. Calculations for future
scenarios indicate that yield-gap closures, achieved with sustainable intensification, would not meet
projected future demands without an increase in agricultural area and in GHG emissions. Yet,
compared to current trends in yield and yield gap closure, scenarios involving healthy diets reduce
the area necessary for cropping by ~5%, pasture by ~25% and the total GHG emissions by ~45% -
sources of savings occurring via a decrease in enteric fermentation and manure emissions, and
carbon sequestration occurring with a return of some crop and pasture lands to natural vegetation.15
INFLUENCE OF GOVERNANCE AND FOOD MILES:
Socioeconomic governance of the food system is also indicated as central to enhancing food
system sustainability. This suggestion is encapsulate by the perspective of improve governance.
This frame emphasises that the concern lies not just with production and consumption: it is the
outcome of unequal relationships between and among producers and consumers, across and within
countries and communities. A full spectrum of interventions is required, including ‘hard’ measures
such as regulations and fiscal instruments, as well as ‘soft’ approaches such as voluntary
agreements, awareness raising and education.2
Concerns of both a macro perspective and local context exist, including altering the terms of trade
between nations, between producers, and between producers and consumers and the advocating
of a central role for smallholders in farming a diverse range of indigenous crops and livestock
breeds for local markets. More localised, diverse systems are seen as better able to deliver the full
range of micronutrients needed for good health than global supply chains which produce and
6
distribute a simplified range of processed, energy- and fat-dense commodities. Furthermore,
tensions exist between human health and the environmental impact of fruit and vegetable
consumption, accounting for ~2.5% of the United Kingdom’s total GHG emissions, with air-freighted
produce, unseasonal produce, prepared (trimmed or chopped) produce, and fragile or highly
perishable produce being major contributors. Tailoring dietary recommendations to regional
circumstances (i.e. favouring healthy foods that can be produced locally) could provide better
outcomes for the environment and public health nutrition while coinciding with an emphasis on
greater self-sufficiency.16
The concept of food-miles partially supports localisation of the global food supply network.17
Transportation creates approximately 11% (0.91 t CO2-eq/yr) of the 8.1 metric tons of greenhouse
gases that an average U.S. household generates annually as a result of food consumption.
However, average final delivery of food accounts for only 4% (0.36 t CO2-eq/yr) of total GHG
emissions. The impact of delivery food-miles may exhibit greater influence when considered the
individual food group, accounting for a low of 1% of red meat’s GHG emissions due to the higher
overall emissions intensity of red meat, food-miles contribute approximately 11% of GHG emissions
for fruits/vegetables. Therefore, localisation may be most apt with regards to specific food groups.
Indeed, “buying local” could achieve around a 4-5% reduction in GHG emissions, however, although
a totally “localised” diet is suggested to reduce GHG emissions per household equivalent to 1,600
km/yr driven, shifting just one day per week’s calories from red meat and dairy to chicken/fish/eggs
or a vegetable-based diet reduces GHG emissions equivalent to 1,230 km/yr or 1,860 km/yr,
respectively. Shifting totally away from red meat and dairy towards chicken/fish/eggs or a vegetable-
based diet reduces GHG emissions equivalent to 8,590 km/yr or 13,000 km/yr, respectively.18
7
FOOD WASTE AND SUSTAINABILITY:
Approximately one third of food produced worldwide is wasted, totalling 1.3 billion tonnes.19
Contributing towards this, in 2007 it was recorded that 8.3 million tonnes of food waste was
produced by British households.20
Food losses and wastage occur throughout the food supply chain and exert the third largest impact
on the environment globally, affecting valuable resources such as land, water and energy. Food
wastage also incurs significant economic and social consequences. For example, the average
British household wastes food and drink worth £470 each year.19
Food losses can be divided into four categories: (1) storage losses (STOR) – losses through
incorrect storage (also prepared food for serving at the buffet which was stored for one more day
preparation, e.g. salads); (2) preparation losses (PREP) – losses occurring during food preparation
and cooking (mostly fruit and vegetable peel, spoiled food, or food which was dropped); (3) serving
losses (SERV) – food remaining from the buffet and serving bowls at the counter; and (4) plate
waste (PLATE) – residue left on consumers’ plates19. Food waste associated with these categories
varies by foodservice sector/environment. For instance, restaurants, cafes, schools and workplace
canteens usually have levels of plate waste of less than 15%; in hospitals, plate waste can be two to
three times higher.21
Among categories for food loss/waste a need exists to differentiate between avoidable and
unavoidable food waste. Unavoidable food waste can be defined as waste that occurs in the
preparation of food: peels, bones, shells, etc., which commonly are not regarded as edible.
Avoidable food waste can be defined as products which could have been eaten and consists of
prepared but uneaten food (e.g. cooked pasta), food left to spoil (e.g. dry bread or rotten fruits and
vegetables) and other foods disposed of in edible condition.22
Food loss and waste is evident throughout the food supply chain, with all processes and impacts
embedded in the food chain – from production to processing, from manufacturing to transport, from
storage to cooking – ultimately embodied in the waste produced (figure 2).23
Figure 2: Division of the produced and lost food supply evidenced throughout the
food supply chain.
8
FOOD WASTE IN THE FOOD SERVICE INDUSTRY:
The food service industry comprises restaurants, cafes, schools and workplace canteens.
Estimations of food waste vary. In Germany, losses in the food service industry are the second
highest source of food wastage and comprise about 17% of the total losses. Similarly, in
Switzerland the food service industry is shown to be the third largest source of food wastage (18%;
13.5% avoidable). However, in a German university canteen specifically, total loss in the value
added chain equated to 9.65%.19
Calculations estimate an average of 7.41 tonnes of food loss per year per food service company (in
the education and business sectors) in the Swiss canton of Aargau. The extent of food waste per
meal ranges from 46-191g, with a study performed in UK secondary schools calculating that pupils
produced 159-191g per meal per day of waste.19
In the food service industry, serving losses make up the highest percentage of all losses and are
considered almost completely avoidable. Further of serving losses, plate waste – mostly avoidable –
contributes to approximately 25% of food waste production. According to customers, portion size is
an important contributor to such waste: if portion size is determined by staff rather than customers,
plate waste is found significantly more often.19
FOOD WASTE IN HOSPITALS:
In hospitals, plate waste is reported to be much higher than in other food service settings such as
restaurants or schools. Reasons for heightened plate waste in hospitals include: (1) clinical
condition of patients; (2) food, namely quality, portion sizes, and available choices; (3) service,
including difficult accessing food and complex ordering systems; and (4) environmental factors,
such as meal times, interruptions, surroundings.24
In the past five years, two case studies have evaluated plate waste in the healthcare setting. In the
Portuguese hospital setting, food waste across wards ranged from 0.462 to 1.395 kg/patient/day,
with patients on average wasting 953 g/d. This amount of waste equates to throwing away 8.7
thousand tonnes of food waste each year.24 In a study of hospitals in Wales, food waste ranged
from 19-66% per meal service. Specifically, plate waste ranged from 6-42% of food cooked, and
trolley waste from 26-55% of food cooked. Based on observations and interviews, significant
training gaps amongst staff were identified, affecting both their direct handling of waste issues and
the quality of service; a lack of effective communication was apparent with many patients served
vegetable choices that they had not ordered, gravy without being asked and portion sizes beyond
their eating capacities. The Wales Audit Office calculated that the cost of un-served meals on 62
sampled wards reached approximately £1.5 million per annum. If all wards could reduce their
wastage to the levels of the best performing quartile in the sample, over £758,000 could be saved.25
Williams & Walton present an overview of studies performed over the last 50 years. According to
their results, and similar to the above, the range for plate waste in hospitals is wide (6-65%), with
the median reported waste at 30% of the plated food waste, 27% of the energy content served and
26% of the protein provided.21 Reasons behind plate waste include low appetite, meal quality issues
and portion size. Issues surrounding appetite are not unexpected, since illness can often affect
appetite and the senses of taste or smell.21,24,25 It’s likely that limited opportunity exists to overcome
clinical barriers to consumption, however issues related to food quality, service and the ward
environment should be more amenable to improvement.21
9
SOURCES OF FOOD WASTE:
In developed countries it’s suggested that meat, fruit & vegetables, bread & bakery products are the
top three major food wastes produced. In the Swiss food service industry, plate waste was found to
consist mainly of starch accompaniments (about two thirds), vegetables (~30%) and followed by
meat and fish. No plate waste was produced in respect of desserts and very little with fruit.19 Similar
to the food service industry, higher amounts of vegetables, meat and starch were found to be
wasted in the hospital setting, whereas fruit and dessert generally have good acceptances and
originate less waste.24 Studies reporting the actual foods wasted are limited, however Williams &
Walton highlight Frakes and colleagues’ findings that over 40% of served vegetables remain
uneaten compared to only 18% of entrees.21 Analysis of trolley waste on wards in three Welsh
hospitals highlighted that overall the main course had the smallest percentage of trolley waste
(33%) and vegetables the largest (46%),25 and, in the Portuguese hospital setting, results showed
that more than 50% of the bread and the main course were wasted, while only 12% of the soup and
10% of the dessert/fruit were.24
INFLUENCE ON CLIMATE:
The relationship between food and sustainability is somewhat complicated. Although it’s understood
that meat and fish require the greatest energy for production, Cuellar & Webber suggest that the
food categories with the greatest embedded energy in their waste are dairy and vegetables. This
discrepancy is suggested to result from the greater proportional waste of dairy and vegetables, in
addition to their energy requirements;26 however, more recent studies appear to suggest that beef,
cheese and rice result in especially high emissions of CO2-equivalents due to large emissions of
methane in the production chain e.g. production of 1 kg of beef results in emissions 120 times larger
than for the production of 1 kg of carrots. According to Schott & Anderson, as much as 22-24% and
7-9% of the GHG emissions from wasted food are related to meat and dairy products, while fruit and
vegetables correspond to 6-10% - this being supported by a study of UK households where 30% of
total GHG emissions from consumption were meat related, 20% dairy and 11% fruits and
vegetables (including exotic fruits). Furthermore, the global warming potential (GWP), derived from
life cycle assessment, associated with avoidable food waste highlights the magnitude of difference
between food groups: the GWP of avoidable meat, vegetable and cheese waste ranges from 5.3-
14.7 kg CO2-eq/kg, 0.7-1.0 kg CO2-eq/kg and 10.8-13.3 kg CO2-eq/kg, respectively. The GWP also
varies within food groups i.e. emissions of 5.6-5.7 kg CO2-eq/kg for pork and chicken versus 32.7 kg
CO2-eq/kg for beef.22
Indeed, food exhibits varied influence on global warming. Regardless, the suggested emissions
related to total food waste are alarming. In the United Kingdom, 28 million tonnes of municipal
waste is produced annually, of which 83% ends up in landfill sites, and is estimated to relate to 20%
of the United Kingdom’s GHG emissions. Around 60% of this municipal waste is biodegradable, with
biodegradable waste being mostly food waste. Each tonne of landfilled food waste is suggested to
generate approximately 125 m3 of landfill gas (at atmospheric pressure). Landfill gas contains 60-
65% methane (CH4) and 35-40% carbon dioxide. Methane has 21 times more global warming
potential compared to carbon dioxide over a time span of 100 years. Landfills are also suggested to
leak leachate into soil and groundwater. Leachate is a potentially toxic liquid, with landfills producing
between 0.17-0.25 m3 of leachate per ton of municipal solid waste.22
Food losses and waste also impact on a variety of scarce natural resources. For instance, the
agricultural sector is responsible for 70% of global freshwater withdrawals and 90% of consumptive
10
water uses, and cropland occupies approximately 1.53 billion hectares (12% of Earth’s ice free
land). According to Kummu et al., globally 24% of total food production analysed is lost or wasted
within the food supply chain, with agricultural losses and consumption waste each accounting for
around 30% of total losses. 24% of total freshwater volume used to produce food products is used
for food supply chain losses. Food supply chain losses correspond to 198 Mha/yr of cropland and
28 Mt/yr of fertilisers (depleting finite resources such as phosphorous and negatively impacting
biodiversity and water quality). To put these values into perspective, the freshwater resourced used
for food supply chain losses equal approximately 12-15% of global consumptive water use and the
total cropland use of food supply losses almost equals the extent of cropland in Africa (221 Mha).
However, according to models proposing minimal losses, water use for food supply chain losses
could be reduced by 44%, 39% of cropland and 42% of fertiliser resources used for food supply
chain losses could be saved and, remarkably, consumption waste could be reduced by 86%
(varying regionally between 0-94%).23
MEASURES TO REDUCE FOOD WASTE:
Strategies to address food loss and waste occupy a hierarchy of benefit: (1) prevention; (2) reuse;
(3) recycling; (4) composting; (5) incineration with energy recovery; (6) landfilling with energy
recovery; (7) incineration without energy recovery; and (8) landfilling without energy recovery.20,21
Table 1 provides an overview of recent suggestions for measures for food waste reduction. In both
the food service industry and hospital environment, a major area is that related to staff. It’s
important to increase staff awareness of the issues regarding food waste and to promote the
adoption effective measures. Training is recommended to clarify problems and highlight the
potential for avoiding food waste.19
Table 1 Measures for food waste reduction.
Storage/purchase
Optimisation of storage management e.g. application of first-in-first-out principle and periodic control of date of expiry
Direct use of food near date of expiry (flexible meal planning)
Long-term analysis of meals sold in order to adapt food orders (with regard to weekday, season, and external factors such as holidays or major events)
Enhancement of order interval and no stock buying
Preparation/cooking
Development of strategies against over production (e.g. freezing)
Reuse of leftovers (under consideration of legislation applicable)
Control of preparation losses and training of employees
Fast cooling down of food to avoid growth of microorganisms
Serving at counter/buffet
No meals for presentation purposes only (use of photographs)
Use of small serving bowls at the buffet (filling as needed)
No complete filling of bowls towards the end of lunchtime
Adaption of portion sizes to customer needs (supply of half portions and second helpings)
Attractive presentation of meals
Consumers
Sensitisation of customers to the field of food waste and the causes of food waste (e.g. using posters)
Increasing tolerance of customers towards sustainability measures through communication
Survey reasons for plate waste using feedback sheets (and subsequent implementation of appropriate actions)
Possible donation of food to local charities
11
The reasons behind food waste in hospitals reviewed by Williams and Walton envisage a wide
range of measures, from improving the pleasantness of meal areas to less disruption of meal times
by medical activities. The most common measures have been those that have tried changing
portion sizes, increasing food choice, greater feeding assistance for patients, and changes to the
meal delivery system. It’s shown that simply increasing meal frequency with smaller meals does not
increase food intake in elderly patients. Increasing the ability of patients to choose their food (with
selective menus and greater ranges of choice) also appears successful in reducing waste. Similarly,
a bulk food service system has consistently been shown to reduce plate waste.21 Previous studies
have suggested that bulk systems contribute to increased intake and consequently less plate
waste.21,24,25 The advantages of bulk over plated meal delivery systems are the possibility of (1)
better addressing the patients requirements in terms of choice and portion size; (2) better
maintaining the food temperature; and (3) improved food appearance/presentation. These three
reasons explain why a reduction of plate waste of more than half (48% to 21%) was attained in
studies when changing from plated to bulk.24
The bulk system possesses some obstacles, such as being difficult to implement. Furthermore, the
downside of bulk systems is that there might be considerable amounts of leftovers in the trolleys,
negating advantages of reducing plate waste. One other measure that might prove easier to
implement is to offer patients two portion-sizes to choose from, deviating from a one-size-fits-all
practice. Previous studies on an elderly rehabilitation hospital report that when portions are too
large that patients are often overwhelmed or discouraged, further reducing appetite. In a
Portuguese hospital setting it was hypothesised that allowing patients to choose from two portion
sizes plate waste could be reduced by at least 30%.24
Results relating to serving losses imply that the bowls at the buffet and serving counter of
restaurants/canteens are fuller than necessary when food distribution has ended, and that large
amounts of food remain at the buffet or serving counter. Measures to reduce this wastage include
the use of smaller serving bowls. Towards the end of mealtimes, empty bowls should be replaced
by half-full ones.19 Similarly, a trayless delivery system could be implemented. In a University dining
hall a significant reduction of 23 g per patron in solid plate waste was observed with a trayless food
delivery system versus a tray system. This reduction, when considering 500 average patrons of the
dining hall per meal equates to savings of 11.4 kg of solid food.27
Another solution to reduce food waste is repurposing food items into products such as soups –
especially food produce discarded for aesthetic reasons, such as apples with bruises or unusual
shapes28 – or donating leftover or surplus food to charities, which would not only have social value,
but may also be useful for marketing purposes.19 Importantly, excess food can be given to people
who need it if it is collected properly and hygienically and the food must be edible and it must not be
spoiled or contaminated.20
Should reuse and recycling be inadequate/unachievable, food wastes can be converted into an
environmentally friendly product if properly used for composting – composting is a biological
process for converting solid or semisolid organic materials to a stable, soil like product, called
compost.22
In addition to measures to reduce food losses during distribution and consumption, possible
interventions should be considered to avoid losses earlier in the food supply chain (table 2)23 –
coinciding with the earlier described food sustainability perspective pertaining to production
challenges: improve efficiency.2
12
Table 2 Brief explanation of definitions of food losses and waste and examples of possible interventions to avoid
losses1
Loss name Definition Possible interventions to avoid losses
Agricultural losses Contains losses due to mechanical damage and/or spillage during harvest operation, crop sorting, etc. Percentage varies from 2% for cereals in industrialised regions (EUR, NAO, INA) to 20% for roots & tubers (EUR, NAO, INA) and fruits & vegetable (EUR, NAO, LAM).
In industrialised countries: cooperation among farmers could reduce risk of overproduction that often leads to agricultural losses. In developing countries: better organised small farmers, technology transfer, education.
Postharvest losses Contains losses due to storage and transportation between farm and distribution, and spillage and degradation during handling. Percentage varies from 0% for oilseeds & pulses in NAO to 19% for roots & tubers in SSEA.
In industrialised countries: improved on-farm facilities. In developing countries: more reliable transportation network, energy and market systems; enhanced infrastructure during transportation and storage.
Processing losses Includes losses during industrial or domestic processing. Percentage varies from 0.5% for cereal products in industrialised regions to 25% for fruits & vegetables in AFR and SSEA.
In industrialised countries: develop market for ‘sub-standard’ products that are eatable, enhanced production lines. In developing countries: capacity building, more investments on food processing.
Distribution waste Includes losses and waste in the market system, including wholesale markets, supermarkets, retailers, and wet markets. Percentage varies from 1% for oilseeds & pulses in industrialised regions to 17% for fruits & vegetables in AFR.
In industrialised countries: lower standards for size, weight, etc. In developing countries: marketing cooperatives and improved marketing facilities.
Consumption waste Includes all the losses and waste at the household level. Percentage varies from 1% for cereals in AFR and oilseeds & pulses in SSEA to 30% for roots & tubers in NAO.
In industrialised countries: public awareness, smaller packages, better planning in restaurants and households. In developing countries: not a big problem as consumption waste is already very low.
1 AFR stands for Sub-Saharan Africa, EUR for Europe (including Russia), INA for Industrialised Asia, LAM for Latin
America, NAWCA for North Africa & West-Central Asia, NAO for North America & Oceania, and SSEA for South &
Southeast Asia.
13
OVERALL SUMMARY OF EVIDENCE AND SUGGESTED
ACTIONS:
The relationship between food and sustainability is multifaceted. It’s estimated that the food system
contributes near to one third of GHG emissions in developed countries, with all stages in the supply
chain contributing.
Global estimates suggest that livestock production accounts for near half of the food system’s total
impacts. This, plus consideration for modelled studies and dietary patterns relating to food
sustainability, predicates one of three perspectives pertaining to food sustainability: demand
restraint.
Studies argue the need to curb global consumption of high-impact foods and that livestock sector
growth places great stress on humanity’s existence. An established and growing body of literature
emphasises that plant-based diets are effective in achieving climate stabilisation goals, reducing
GHG emissions, and reducing resource utilisation whilst exploiting a potentially synergistic
relationship between healthy diets and sustainability; however, suggestions of total elimination of
meat and dairy from the diet are equivocal and likely to be unacceptable for a number of cultural,
nutritional, and economic reasons for both consumers and producers.12
Demand restraint suggests a resolution via consumption and subsequent product demand.
Alternatively, improved efficiency focuses its attention on what can be done now, through better
technologies and good management, to address immediate nutritional and environmental problems:
breeding, feeding and housing strategies, together with research can reduce the environmental
footprint of food production. However, enhanced efficiency of production alone appears inadequate,
partly explaining the growing recognition from international observers that consumption issues merit
further consideration.2
Alterations in demand and improvements in efficiency both seem feasible measures to ameliorate
challenges relating to food and sustainability. Furthermore, governance – in particular trade
agreements and localisation – influences food sustainability. Trade between nations, producers and
consumers clearly posses economic influence, however trade also affects transportation.
Localisation may not only restrict GHG emissions associated with transportation and food
consumption but also place greater emphasis on self-sufficiency, and develop local food systems
and markets.
Concerns regarding production, consumption and associated governance highlight the reality that to
tackle food sustainability a composite approach is necessary. However, this is further complicated
by the influence of food loss/waste – exerting the third largest impact on the environment globally,
affecting resources such as land, water and energy.
The perspective of improved efficiency could be suitably applied to food waste. Approximately 20%
of the United Kingdom’s GHG emissions relate to municipal waste, of which a considerable portion
is suggested to be food waste.20 Waste specifically pertains to food distribution and consumption.
Significant amounts of waste are avoidable, typically arising from serving and plate waste, thus
demanding a need for enhanced efficiency – much of which can be achieved through relatively
simply measures.
14
Tackling concerns regarding food waste – and food sustainability in general – requires a
comprehensive approach. Reductions in losses/waste must be targeted throughout the food supply
chain. And, importantly, interventions should adhere to the hierarchy of benefit,20,22 specifically
prevention, reuse and recycling – the former of which should be stressed for all challenges relevant
to food sustainability.
SUGGESTED ACTIONS TO TAKE:
Mitigating the influence of food on climate change and sustainability necessitates multiple actions.
The evidence provided primarily within the last five years clearly indicates a need to implement
initiatives parallel to one another to facilitate significant improvements. Consumption appears to
exhibit the greatest level of influence on sustainability, including its relation to food waste, and
targeting this may pose the greatest effect. Regardless, analysis of the evidence suggests that a
successful programme could include a combination of the following levers:
1. Introduction of a broad, structured and transparently monitored programme of gradual
dietary change, rebalancing and reformulating food provisions/menus to reduce
consumption of high-impact foods.
2. Adopt, implement and monitor the government buying standards for food and catering
standards to ensure provision of healthier and sustainable food and drinks.
3. Implementation of preventative measures for the reduction of food waste, including food
delivery, waste measurement, technological improvements and routine staff training
and education. Ultimately adhering to the hierarchy of benefit.
4. Limit trade agreements and develop partnerships with stakeholders, including local
smallholders to promote localisation and reduce food-related transport emissions.
5. Raise awareness of concerns around food sustainability to the public as well as health
professionals, employers, the food industry etc, encourage action to reduce
environmental impact and provide practical steps to help promote sustainable behaviours.
6. Procure livestock and other foods from more efficient, sustainable sources e.g. organic
agriculture.29
Successfully alleviating concerns around food sustainability depends not only on a stringent and
varied approach but cooperation from a wide range of people and organisations is fundamental to
change. To achieve targets for climate change and reduced greenhouse gases we must act without
further delay.
15
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