Lost food, wasted water:
global food supply chain losses and their impacts on freshwater use
Reducing food losses and waste is considered to be one of
the most promising measures to improve food security in
the coming decades [1]. Food losses also affect our use of
resources, such as freshwater, cropland, and fertilizers.
largest per capita food supply losses occur in North America
& Oceania (1334 kcal/cap/day) and the lowest in South &
Southeast Asia (404 kcal/cap/day) (Fig 2A). The per capita
use of water resources for food losses is largest in North Africa
& West-Central Asia while it is the smallest in Sub-Saharan
Africa (Fig 2B).
Objectives
In this study we aim to estimate the global food supply losses
due to lost and wasted food crops, and the water resources
used to produce these losses. We also aim to quantify the
potential savings of food supply and related resources that
could be made by reducing food losses and waste.
The freshwater resources used for FSC losses account for 215
km3/yr, which is around 12-15% of the global consumptive
water use. In three countries, the use of water resources for
FSC losses exceeds the available resources, namely Kuwait
(595%), Saudi Arabia (115%), and United Arab Emirates
(222%).
We used publically available global databases to conduct the
study at the country level. The food supply chain (FSC) data
were derived from FAO Food Balance Sheets [2], food loss and
food waste percentages from Gustavasson et al [3] and water
footprint data from Mekonnen and Hoekstra [4].
If the lowest loss and waste percentages achieved in any
region in each step of the FSC could be reached globally,
food supply losses could be halved. By doing this, there
would be enough food for approximately one billion extra
people. Reducing the food losses and waste would thus
be an important step towards increased food security, and
would also increase the efficiency of water resources use
in food production.
We found that around one quarter of the produced food supply
intended to human food (614 kcal/cap/day) is lost within
the FSC (Fig 1A). The production of these lost and wasted
food crops accounts for 24% of total freshwater resources
used in food crop production (27 m3/cap/yr) (Fig 1B). The
3%
3%
27%
140
Food supply chain (FSC)
16%
(24%)
51%
(76%)
Consumed
kcal as food
(1995 kcal/cap/day)
SUMMARY
Water resources (WR) used for
products directed to human food
(111 m3/cap/yr)
Posth. l.
Distrib.
(5.7) Proc.l. waste Cons.w.
(1.0 ) (3.7)
100 Agric.
(7.4)
losses
(9.3)
50
0
“
3%
2%
14%
Consumption (crop)
Consumption (crop)
Distribution (crop)
Processing (crop)
0
Field (crop)
1000
Postharvest (crop)
2000
Posth. l.
Distrib.
Proc.l.
(129)
waste Cons.w.
(28)
(68)
(214)
Agric.
losses
(181)
Other use (2.7 m3/cap/yr)
Seed (4.0)
Feed (19)
Distribution (crop)
Food supply of human food
(2609 kcal/cap/day)
kcal lost & wasted
within FSC
(614 kcal/cap/day)
WR used for
other purposes
(26 m3/cap/yr)
Total water resources used
(137 m3/cap/yr)
Processing (crop)
3000
Water resources (m3/cap/yr)
Food supply energy (kcal/cap/day)
Other use (135 kcal/cap/day)
Seed (122)
Feed (1072)
B.
Postharvest (crop)
Total supply
4000 (3938 kcal/cap/day)
Field (crop)
A.
Food supply
losses
[kcal/cap/day]
< 500
500- 750
750 - 1000
1000 - 2080
No data
Discussion and conclusions
Results
Consumed kcal
for other purposes
(1329 kcal/cap/day)
A.
Food supply chain (FSC)
WR used for
FSC losses
(27 m3/cap/yr)
20%
(24%)
62%
(76%)
WR used for
consumed food
(84 m3/cap/yr)
SUMMARY
Around 1/4 of the
food supply of
produced food, and
used water resources,
are lost in the food
supply chain
Figure 1: Division of the produced
and lost food supply, and water
resources used for production
and FSC (food supply chain)
losses averaged over the years
2005-2007; A: food supply
(kcal/cap/day); B: water resources
(WR; m3/cap/yr). The losses
and waste are calculated in our
analyses only for the fraction
intended to human food.
B.
Water resources
used for losses
[m3/cap/yr]
< 20
20 - 40
40 - 80
80 - 177
No data
Figure 2: Country results of A: Food supply losses and waste; and B:
Per capita water resources used for FSC losses.
References
1. Foley J A et al 2011 Solutions for a cultivated planet. Nature 478
337-42.
2. FAO 2011 FAOSTAT - FAO database for food and agriculture.
3. Gustavsson J, et al 2011 Global food losses and food waste: extent,
causes and prevention. Report for FAO
4. Mekonnen M M and Hoekstra A Y 2011 The green, blue and grey
water footprint of crops and derived crop products Hydrology and
Earth System Sciences 15 1577-600
M. Kummu1*, H. de Moel2,3, M. Porkka1, S. Siebert4, O. Varis1, P.J. Ward2,3
Water & Development Research Group (WDRG), Aalto University, Finland
2 Institute for Environmental Studies (IVM), VU University Amsterdam, The Netherlands
1
* more information: [email protected] & www.wdrg.fi
Amsterdam Global Change Institute (AGCI), VU University Amsterdam, The Netherlands
4 Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Germany
3
“
One billion extra people
could be fed if food crop
losses could be halved