Our diets can have an enormous environmental influence. The greenhouse fuel emissions concerned in producing and transporting varied meals has been effectively researched, however have you ever ever thought in regards to the water-scarcity impacts of manufacturing your favorite meals? The solutions could shock you.
In analysis not too long ago printed within the journal Vitamins, we regarded on the water shortage footprints of the diets of 9,341 grownup Australians, involving greater than 5,000 meals. We measured each the quantity of water used to provide a meals, and whether or not water was scarce or ample on the location it was drawn from.
The meals system accounts for round 70% of worldwide freshwater use. This implies a concerted effort to minimise the water used to provide our meals – whereas guaranteeing our diets remained wholesome – would have a big effect in Australia, the driest inhabited continent on Earth.
Biscuits, beer or beef: which takes probably the most water to provide?
We discovered the common Australian’s diet had a water-scarcity footprint of 362 litres per day. It was barely decrease for ladies and decrease for adults over 71 years of age.
A water-scarcity footprint consists of two components: the litres of water used, multiplied by a weighting relying on whether or not water shortage on the supply is increased or decrease than the worldwide common.
Meals with a number of the highest water-scarcity footprints have been almonds (3,448 litres/kg), dried apricots (3,363 litres/kg) and breakfast cereal created from puffed rice (1,464 litres/kg).
In distinction, meals with a number of the smallest water-scarcity footprint included wholemeal bread (11.Three litres/kg), oats (23.four litres/kg), and soaked chickpeas (5.9 litres/kg).
It might shock you that of the 9,000 diets studied, 25% of the water shortage footprint got here from discretionary meals and drinks comparable to muffins, biscuits, sugar-sweetened drinks and alcohol. They included a glass of wine (41 litres), a single serve of potato crisps (23 litres), and a small bar of milk chocolate (21 litres).
These meals don’t solely add to our waistlines, but in addition our water-scarcity footprint. Earlier research have additionally proven these meals contribute round 30% of dietary greenhouse fuel emissions in Australia.
The second highest meals group by way of contributing to water-scarcity was fruit, at 19%. This consists of complete fruit and recent (not sugar-sweetened) juices. It ought to be remembered that fruit is a vital a part of a wholesome diet, and customarily Australians have to devour extra fruit to fulfill suggestions.
Dairy merchandise and alternate options (together with non-dairy drinks created from soy, rice and nuts) got here in third and bread and cereals ranked fourth.
The consumption of purple meat – beef and lamb – contributed solely 3.7% of the whole dietary water-scarcity footprint. These outcomes recommend that consuming recent meat is much less vital to water shortage than most different meals teams, even cereals.
Find out how to cut back water use in your diet
Not surprisingly, reducing out discretionary meals could be primary precedence for those who wished to decrease the water footprint of the meals you eat, in addition to the greenhouse fuel emissions of manufacturing.
Over-consumption of discretionary meals can also be carefully linked to weight achieve and weight problems. Consuming a wide range of wholesome meals, based on vitality wants, is a useful motto.
Apart from this, it’s tough to provide suggestions which can be related to customers. We discovered that the variation in water-scarcity footprint of various meals inside a meals group was very excessive in comparison with the variation between meals teams.
For instance, a medium sized apple was discovered to contribute a water-scarcity footprint of three litres in contrast with greater than 100 litres for a 250 ml glass of recent orange juice. This displays the relative use of irrigation water and the native water shortage the place these crops are grown. It additionally takes extra fruit to provide juice than when fruit is consumed complete.
Two slices of wholegrain bread had a a lot decrease water-scarcity footprint than a cup of cooked rice (0.9 litres in contrast with 124 litres). Of the principle protein sources, lamb had the bottom water-scarcity footprint per serve (5.5 litres). Lambs are not often raised on irrigated pastures and when crops are used for feeding, these are equally not often irrigated.
Shoppers usually lack the data they would wish to decide on core meals with a decrease water-scarcity footprint. Added to this, range is a crucial precept of fine diet and dissuading consumption of specific core meals might have adversarial penalties for well being.
Maybe the most effective alternatives to cut back water shortage impacts within the Australian meals system lie in meals manufacturing. There may be usually very giant variation between producers in water shortage footprint of the identical farm commodity.
For instance, a examine of the water shortage footprint of tomatoes grown for the Sydney market reported outcomes starting from 5.Zero to 52.eight litres per kg. Variation within the water-scarcity footprint of milk produced in Victoria was reported to vary from 0.7 to 262 litres. This primarily displays variations in farming strategies, with variation in the usage of irrigation and in addition the native water shortage stage.
Water-scarcity footprint reductions might finest be achieved via technological change, product reformulation and procurement methods in agriculture and meals industries.
Not all water is equal
That is the primary examine of its form to report the water-scarcity footprint for numerous particular person self-selected diets.
This was no small process, on condition that 5,645 particular person meals have been recognized. Many have been processed meals which wanted to be separated into their part components.
It’s laborious to say how these outcomes evaluate to different international locations as the identical evaluation has not been executed elsewhere. The examine did present a big variation in water-scarcity footprints inside Australian diets, reflecting the variety of our consuming habits.
Water shortage is only one vital environmental features of meals manufacturing and consumption. Whereas we don’t recommend that dietary tips be amended based mostly on water shortage footprints, we hope this analysis will assist extra sustainable manufacturing and consumption of meals.