Download BNF sustainability.

A sustainable diet is a
healthier diet?
Roy Ballam, BNF
Thank you to Prof Judy Buttriss
Diet and nutrition
• Why is sustainability an important
consideration?
• What does sustainability mean?
• What does a nutritious diet look like and
how does this compare with what we eat
currently in the UK?
• What would the impact on health be if
such a diet were to be consumed?
• Are the two characteristics –
sustainability and healthiness compatible?
• What are the challenges ahead ….. ?
What does the future hold?
Global nutrition and health
challenges: double burden in 21st
century
~1 billion
people go to
bed hungry
Another billion
have micro-nutrient
deficiencies.
Poor diet quality.
>1 billion
adults are
overweight or
obese
Poor growth, nutrient
deficiencies, infection,
intergenerational
effects
Need healthy, sustainable, low impact
food supply that is affordable by all.
Living longer: 2 years
per decade in UK
Family food
Chad:
Food expenditure for one week US $1.23
Ecuador:
Food expenditure for one week US $31.55
• Impact of climate
change on what we
can grow
• Increasing prosperity
• Increasing lifespan
• Increasing global
population
Germany:
Food expenditure for one week US $500
FSA consumer survey:
key findings
• People are not used to thinking globally about food.
• People recognise the importance of the challenges faced but
were concerned to realise how little they knew about the
complex global food system.
• Would like to know more about:
– Links between our food production systems and climate
change
– The complexity of the global farm to fork process
– The role of the food industry in shaping global food trends
– The role of government in working with global industry.
• Convenience versus connection with food:
- Participants didn’t want to sacrifice convenience but also
didn’t want a ‘connectionless future’
• Saw a need to strike a balance between health and quality,
and price. [Same priorities emerged in a study by Which? and
GO Science, 2015]
Multiple challenges ahead
CHALLENGES
• Increasing global population.
• Increasing lifespan.
• Double burden of over- and
undernutrition.
• Increasing prosperity (and
changing demand for foods).
• Expected impact of climate
change on what we can grow.
Need healthy, sustainable, low
impact food supply that is
affordable by all.
• Global food supply has to be
sustainable.
• Global food supply has to be
nutritious/promote health.
• Both are necessary, indeed
essential for the human race is
to survive.
• Are they compatible?
In the UK alone, we produce less than
60% of our own food, and import the
rest from over 180 countries
New technology and new sources of
food will change what’s available.
Climate change (& extreme weather) and
rising income in developing countries will
change the global picture.
Complex pressures on supply chains
bring challenges – traceability, volatile
prices and even crime.
https://www.food.gov.uk/news-updates/campaigns/ourfoodfuture#sthash.vd6p95OZ.dpuf
Global GHGs from food
approximate 30% of total
Inputs eg. fertilisers,
manure, pesticides
About 20%
Home: cooking, fridge,
washing up
Land use change
Farming
Supermarkets, shops,
markets
Waste disposal
Slaughtering, processing,
manufacturing
1.3 billion people involved in
producing food - livelihoods
Arrows = transport
Restaurants, school
canteens etc.
Packaging
About 10%
Vermeulen, S. J. et al.(2012) Climate Change and Food Systems.
Annual Review of Environment and Resources. 37. p.195-222.
To support health, food needs
to be nourishing!
• Predicted that by 2030, the world will need to produce 50% more food
than now and to secure 30% more fresh water (Population Institute
2010)
• FAO predicts that by 2050, the expanded population will be consuming
two-thirds more animal protein (FAO 2013)
• Growing emphasis on plant-based diets (less environmental impact;
though even this is influenced by where and how the foods are grown)
• But need to be certain that essential nutrients will still be delivered in
adequate amounts - Important role for dietary data, as well as
analysis of environmental impact – to ensure sustainable diets are also
nutritious.
• Multi-disciplinary approach to research essential to integrate the
many facets of a sustainable food supply (e.g. including water but also
livelihood/economics/social aspects).
• Dissemination of findings into practice.
What is sustainability &
why is sustainability of the
food supply so critical?
It implies the use of resources
at rates that do not exceed the
capacity of the earth to replace
them.
Complex interaction of factors.
Trade-offs involving the food supply and ecosystem will
need to be identified, accepted and adopted.
What does a nutritious diet look like?
How does this compare with what we
eat currently in the UK?
Is the current British diet
healthy?
Recommendation
Progress vs. recommendation
Fruit and veg
X
4.1 serves a day (at least 5)
Oily fish
X
54g/week (at least 140g/week)
Sugars (NMES/’free’)
X
12.3% energy (<5% energy)
Fat

34.7% energy (35%)
Saturated fat
X
12.7% energy (<11%)
Trans fat

0.7% energy (below 2%)
Fibre
X
~18g AOAC fibre/day (30g AOAC)
Starchy carbs
X
Below 50% energy target
Salt
X
8.1g/day (<6g/day)
Vitamins & minerals
 and X
Some groups have low intakes of
some of these
Vitamins and minerals evidence of low intakes
% with intakes below LRNI
GIRLS 11-18 years
% with intakes below LRNI
BOYS 11-18 years
Vitamin A
18
14
Riboflavin
20
8
Folate
8
5
Iron
48
9
Calcium
19
12
22 [13% 4-10 year olds]
17 [4% 4-10 year olds]
Magnesium
48
27
Potassium
33
15
iodine
26
16
Selenium
44
23
Zinc
Current UK consumption vs ‘Eatwell
Guide’ scenario and the ‘old
recommendations’* scenario
Peter Scarborough et al. BMJ Open 2016;6:e013182
%
* ie lower fibre and higher
NMES
The challenge
Eatwell guide
Starchy
foods
High
fat/sugar
Milk etc.
Beans, meat
etc.
Fruit & veg
Comparison of the impacts of the
Eatwell Guide compared with
current diet (Carbon Trust 2016)
DALYs* averted (millions) over the
lifetime of the UK population
Cobiac et al 2016 doi:10.1371/journal.pone.0167859.g001
Changing from ‘average’ UK
diet to the eatwell diet (with
no rise in energy intake)
would:
• avert 17.9 million DALYs
over the lifetime of current
population
• Increase life expectancy
by 5.4 months in men and
4 months in women
• Benefits re: type 2
diabetes, in particular,
also CVD and colo-rectal
cancer
* Disability adjusted life years
Systematic review
Aleksandrowicz et al 2016
• Reviewed evidence on changes
in GHG emissions, land use
and water use from shifts in
dietary pattern
• Found 14 sustainable dietary
patterns, with reductions as
high as 70-80% (GHG and land
use) and 50% (water)
• Reductions in environmental
footprints generally proportional
to magnitude of animal-based
food restriction.
• Dietary shifts also gave modest
benefits in all-cause mortality
risk.
CONCLUDED:
• Environmental and health
benefits are possible by
shifting current western diets
to a variety of more
sustainable patterns.
So, the story so far …
• Eatwell guide modelling.
• Carbon Trust analysis shows
reduced environmental impact.
• Disability adjusted life years
averted and positive impact on
life expectancy.
• Systematic review - modest
benefits in all cause mortality
risk, as well as reduced
environmental footprint.
Diets can be constructed that
are both healthier than current
diets in terms of achieving
dietary recommendations and
with a lower environmental
impact.
How achievable are modelled
diets such as eatwell?
• FAO (2013) predicts that by
2050, expanded global
population will be consuming
two-thirds more animal
protein, with meat
consumption rising nearly
73% and dairy growing by
58%.
Need to understand:
• Production of these requires
more natural resources than
staple crops, e.g. wheat and
rice.
• Substitutions and impact on overall
nutritional quality of diets, including
bioavailability (Green et al 2103,
2015).
• Public’s priorities and expectations.
• Public dialogue –Which? &GOS
2015; FSA 2016.
• Response to messages designed to
encourage more sustainable dietary
patterns.
• Impact on health (Milner et al 2015).
Impact of substitutions on
nutrition and the environment
• Critically important to understand substitutions – for example, if less
animal protein is eaten, what replaces it and what is the effect of this on
nutrition and on the environment?
• Is it possible to reduce ‘greenhouse gas’ emissions and also
achieve nutrition recommendations?
• Green et al. 2015, modelling using NDNS:
• If average diets conform to WHO dietary recommendations, GHG
emissions would reduce by 17%.
• Further reductions could be achieved but would need greater dietary
change
• Reductions beyond 40% through dietary change alone will be
unlikely without radically changing current dietary patterns and
potentially reducing the nutritional quality of diets.
Impact on health of diets with
lower GHG emissions
(Milner et al 2015)
• Estimated dietary changes in the
UK that would meet nutrition and
climate change mitigation targets.
• Also accounted for potential
acceptability (consumer
behaviour data).
• Radical change in diet, e.g.
veganism not necessary to
reduce emissions and bring
quantifiable benefits to health (av.
life expectancy increased by 8
months).
• Reduction >40% may place limits
on health benefits.
Modelled health impacts associated
with dietary changes in the UK for
different levels of greenhouse gases
(GHG) reduction.
What is needed to achieve
sustainable nutrition?
• Changes in land use and
agriculture – protein.
• Changes in food
production/diet.
• Changes in behaviour:
consumers through to
governments.
• Trade-offs identified,
accepted and adopted,
e.g. technologies, more
plants, less animal protein.
17 United Nations Sustainable Development Goals:
8 directly or indirectly relate to agriculture and food
What does the future hold?
• Environmental and health benefits appear
possible if diets are changed.
BUT
• Billion people in developing world now
‘middle class’ and have different dietary
aspirations.
• To achieve the UN goals; big decisions
needed:
– Land use
– Crops for the future (yield not the only
metric)
– Use of technologies
– Waste avoidance
• Impact on dietary choices and dietary
advice
• Where will sustainable protein come
from?
Biofortification
Tapping into plant biodiversity and the oceans’ bounty
Fungi, e.g. mycoprotein
Snacking on deep-fried grasshoppers
Mealworm, cricket and
grasshoppers with polenta chips!
To sum up:
• Health gains are likely to result from a
shift from current diets to ones that
conform to the eatwell guide.
• The eatwell pattern has been shown to
be more ‘sustainable’.
• This shift will require a substantial
change in dietary behaviour.
• Research is needed to identify ways to
motivate people to make this shift.
Thank you for listening.
For further information, go to: www.nutrition.org.uk