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Implications of Achieving Healthy and Environmentally Sustainable Diets on the Demands for Future Land Use in Scotland
Henri de RuiterUniversity of AberdeenJames Hutton Institute
Healthy and Sustainable DietsIn January, I stayed in a Scottish Bed & Breakfast
This was my breakfast:
Healthy and Sustainable DietsWhen I first came here in October, I learned about more
notorious things:
The deep-fried Mars bar
“We conclude that Scotland's deep-fried Mars bar is not just an urban myth.”
“Encouragingly, we did also find some evidence of the penetrance of the Mediterranean diet into Scotland…”
“… albeit in the form of deep-fried pizza.”
UnsustainableHigh GHGe/Land use
SustainableLow GHGe/Land use
Healthy (meets RNI)
Unhealthy(doesn’t meet RNI)
Current P
roject
Why research on diets?Two main global problems:
1. Obesity & Non-communicable diseases
2. Climate change
Food consumption lies at the basis of both problems
24% of deaths in UK can be attributed to dietary risks (GBD, 2010)
Agriculture accounts for 15-30% of GHG emissions (largest contributor)
UnsustainableHigh GHGe/Land use
SustainableLow GHGe/Land use
Healthy (meets RNI)
Unhealthy(doesn’t meet RNI)
Current P
roject
Meat reduction – Environmental impacts
VEGAN
VEGETARIANOMNIVOROUS
Baroni et al. (2007) European Journal of Clinical Nutrition
Meat reduction – Health implicationsReduced meat consumption may benefit the environment
Other research: also health benefits (processed meat)
3.2% risk reduction for diabetes in women
12.2% risk reduction for colorectal cancer in men
Aston et al. (2012) BMJ Open
However:
Animal protein is ‘the best protein you can get’
‘Bioavailability’ of plant-based protein is lower
It is more difficult to get all your essential (micro) nutrients from plant-based diets
A win – win situation?
UnsustainableHigh GHGe/Land use
SustainableLow GHGe/Land use
Healthy (meets RNI)
Unhealthy(doesn’t meet RNI)
Vegan diet
Vegetarian diet
Meat reduction
It gets more complicatedMost researchers agree: a reduced meat consumption is
beneficial
But environmental impact depends on compensation of meat
Vieux et al. (2013): People consuming a healthy diet have higher associated GHG emissions
Fruits and vegetables: low GHG emissions per gram
Expressed per kcal in the same order as animal products!
UnsustainableHigh GHGe/Land use
SustainableLow GHGe/Land use
Healthy (meets RNI)
Unhealthy(doesn’t meet RNI)
Vegetarian dietHigh in veg/fruit
Vegan diet
Vegetarian diet
Meat reduction
Vegetarian dietHigh in sugar
Let’s add more complexityWhich environmental indicator do we use?
GHG emissions, land use, water use, phosphorus use, etc.
Current projects focuses on land use
38% of total land is already in use for the production of food and this will increase (Foley, 2011)
Global dietary change will contribute to the increasing demand for land
Cropland vs. grassland
Stefan Wirsenius , Christian Azar , Göran Berndes
How much land is needed for global food production under scenarios of dietary changes and livestock productivity increases in 2030?
Agricultural Systems Volume 103, Issue 9 2010 621 - 638
DIETARY CHANGE SCENARIOS
Fig. 7 Extent of global agricultural land in scenarios for 2030. Cropland area includes land used also for non-food crops (mainly cotton and rubber), which FAO projects to be roughly 50 Mha in 2030. It also includes land use for cultivation of food-type cr...
Main challengeNo uniform measure of dietary/nutritional quality
No uniform measure of sustainability
No uniform way of coupling nutritional quality with life cycle assessments of food products
Add to this the social dimensions food security and access, animal welfare, consumer acceptance…
Quest for a healthy food system truly is a ‘wicked’ problem
Future directionsStart with food consumption of Scotland
Combine this with land requirements for food items (either local or FAO)
Based on the preliminary results, I’ll choose how to continue
Future directionsWhat I’d like to investigate:
We have to move away from traditional yields (ton/ha) to nutritive value per hectare
Is it worthwhile to explore a more spatial approach of land use (impact is local, contrary to GHG emissions)
Is it worthwhile to investigate different socioeconomic groups? Cf. health inequalities vs. impact inequalities
Thanks for your attention!
Henri_de_Ruiter
henrideruiter.com
