Global diet and farming methods 'must change for environment's sake'

June 16, 2017
Credit: Jm Verastigue/public domain

Reducing meat consumption and using more efficient farming methods globally are essential to stave off irreversible damage to the environmental, a new study says.

The research, from the University of Minnesota, also found that future increases in agricultural sustainability are likely to be driven by dietary shifts and increases in efficiency, rather than changes between food production systems.

Researchers examined more than 740 production systems for more than 90 different types of food, to understand the links between diets, agricultural production practices and environmental degradation. Their results are published today in the journal Environmental Research Letters.

Lead author Dr Michael Clark said: "If we want to reduce the environmental of agriculture, but still provide a secure food supply for a growing global population, it is essential to understand how these things are linked."

Using life cycle assessments - which detail the input, output and environmental impact of a food production system - the researchers analysed the comparative environmental impacts of different food production systems (e.g. conventional versus organic; grain-fed versus grass-fed beef; trawling versus non-trawling fisheries; and greenhouse-grown versus open-field produce), different agricultural input efficiencies (such as feed and fertilizer), and different foods.

The impacts they studied covered levels of land use, greenhouse gas emissions (GHGs), fossil fuel energy use, eutrophication (nutrient runoff) and acidification potential.

Dr Clark said: "Although high agricultural efficiency consistently correlated with lower environmental impacts, the detailed picture we found was extremely mixed. While organic systems used less energy, they had higher land use, did not offer benefits in GHGs, and tended to have higher eutrophication and acidification potential per unit of produced. Grass-fed beef, meanwhile, tended to require more land and emit more GHGs than grain-fed beef."

However, the authors note that these findings do not imply conventional practices are sustainable. Instead, they suggest that combining the benefits of different production systems, for example organic's reduced reliance on chemicals with the high yields of conventional systems, would result in a more sustainable agricultural system.

Dr Clark said: "Interestingly, we also found that a shift away from ruminant meats like beef - which have impacts three to 10 times greater than other animal-based foods - towards nutritionally similar foods like pork, poultry or fish would have significant benefits, both for the environment and for human health.

"Larger dietary shifts, such as global adoption of low-meat or vegetarian diets, would offer even larger benefits to environmental sustainability and human health."

Co-author Professor David Tilman said: "It's essential we take action through policy and education to increase public adoption of low-impact and healthy foods, as well the adoption of low impact, high efficiency agricultural production systems.

"A lack of action would result in massive increases in agriculture's environmental impacts including the clearing of 200 to 1000 million hectares of land for agricultural use, an approximately three-fold increase in fertilizer and pesticide applications, an 80 per cent increase in agricultural GHG emissions and a rapid rise in the prevalence of diet-related diseases such as obesity and diabetes.

Professor Tilman added: "The steps we have outlined, if adopted individually, offer large environmental benefits. Simultaneous adoption of these and other solutions, however, could prevent any increase in agriculture's environmental impacts. We must make serious choices, before agricultural activities cause substantial, and potentially irreversible, environmental damage."

Explore further: Edible insects could play key role in cutting harmful emissions

More information: Michael Clark et al, Comparative analysis of environmental impacts of agricultural production systems, agricultural input efficiency, and food choice, Environmental Research Letters (2017). DOI: 10.1088/1748-9326/aa6cd5

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Eikka
5 / 5 (4) Jun 16, 2017
Dr Clark said: "Interestingly, we also found that a shift away from ruminant meats like beef - which have impacts three to 10 times greater than other animal-based foods - towards nutritionally similar foods like pork, poultry or fish would have significant benefits, both for the environment and for human health.


Beef is a byproduct of milk production, or vice versa, whichever way you want to look at it.

No beef, no cheese, no milk, no cream, no butter... of course artifical substitutes like hydrogenated vegetable oils exist, but they tend to be unhealthy or even dangerous to eat (trans fats).

nrauhauser
4 / 5 (4) Jun 16, 2017
I caught Lyme ten years ago and as a dubious benefit, I'm now allergic to the carbs in red meat. I found I was gluten intolerant a few years prior to that, so I've become a sort of obligate vegan. I would love to have a proper pizza every once in a while, but given the restrictions I face what's available is more like high end cardboard.

That being said, it amazes my friends when we end up shopping together, since I also shun high fructose corn syrup out of health concerns. There are whole aisles in the grocery store that contain nothing that's safe for me to eat. If we make this much needed transition it'll be an enormous social shift, so much 'comfort food' is going on the chopping block.
patnclaire
1 / 5 (1) Jun 16, 2017
What is the appealing looking food depicted in the accompanying photo?
OverTheMoon
5 / 5 (1) Jun 17, 2017
Looks like Indian food, I suspect veggie, rice at the right of the photo and various curries.
MadScientist72
1 / 5 (2) Jun 17, 2017
Beef is a byproduct of milk production, or vice versa, whichever way you want to look at it.
No beef, no cheese, no milk, no cream, no butter... of course artifical [sic] substitutes like hydrogenated vegetable oils exist, but they tend to be unhealthy or even dangerous to eat (trans fats).


Goats and sheep are also used for milk, cheese & butter. (They COULD be used for cream too, but I don't if they ARE.) Cows are not essential to the process - technically, any mammal could work.

Looks like Indian food, I suspect veggie, rice at the right of the photo and various curries.

And a basket of naan in the back (top of pic).
MadScientist72
1 / 5 (4) Jun 17, 2017
We could also accomplish much the same thing by perfecting "lab meat", but the people pushing these dietary & agricultural changes tend to be supporters of / activists for the vegan, organic and anti-GMO movements, so they don't want people thinking about that option.
Eikka
5 / 5 (2) Jun 18, 2017
Goats and sheep are also used for milk, cheese & butter. (They COULD be used for cream too, but I don't if they ARE.) Cows are not essential to the process - technically, any mammal could work.


Goats don't make a lot of milk, and the taste and texture of the resulting cheese is entirely different. It's tart, and it doesn't melt. Think feta and halloumi cheese - you can cut a slice and grill it. You can't make a pizza with goats cheese, though it works fine for toppings.

The point is that for goats, or cows, to produce milk they must get pregnant, and so you get a lot of calves which have no use except as food. It would be a terrible waste to just kill them, and a terrific trouble if they were left alive because the you'd simply drown in cows.
Eikka
5 / 5 (1) Jun 18, 2017
Oh, and leather as well. Shoes and belts and gloves, jackets, wallets, upholstery, and also some technical parts like gaskets. No cows, no cheap cow leather.
Bart_A
1 / 5 (1) Jun 18, 2017
Dr Michael Clark looks like he just received his PhD and actively researches dietary changes and their environmental impacts. No surprise here.

What I think really is needed is a downsizing per serving of beef consumption (and of course other foods, too). No one really needs a 32 oz steak. Not even 20oz steaks. The portions I get served are always way too big. Just by cutting down on this excess food, which would also get rid of the obesity problem, would have a big impact!
Eikka
not rated yet Jun 19, 2017
The portions I get served are always way too big.


Make your own, then.

Ah, but the problem is, we have to eat out in a restaurant several times a week, where we have no portion control because the establishment has to push us more food to charge us more money. Otherwise the "services" economy stops working - it would be terribly selfish for us to conserve our money and save it, and eat less, since 80% of the people derive their income from selling you this and that. You HAVE to buy and consume, you HAVE to over-eat and become ill or else the economy stops and people go homeless and die.

Isn't that the tragedy?
antialias_physorg
5 / 5 (2) Jun 19, 2017
We could also accomplish much the same thing by perfecting "lab meat"

They're still working on that one. It seems that there's a problem with taste. But it would definitely be nice to get that working as I can't see animal farms being viable e.g. off-world. The alternative would be a fully vegan diet for any kind of space/exoplanet settlement or long duration spaceflight. I'm unsure whether that is a good idea. Vegan diets are OK for adults, but for children the research on this has thrown up some mixed results.

(This is just in addition to any argument that can be made on ethical and environmental grounds)
Eikka
5 / 5 (1) Jun 19, 2017
It seems that there's a problem with taste


If they can make chunks of wet cardboard made of soy taste acceptable, I don't think there's an issue of taste for lab meat. It's just down to seasoning.

The real problem is price. Millions of dollars per pound for cultured tissue.
MadScientist72
not rated yet Jun 20, 2017
Goats don't make a lot of milk


While it's true that a goat will only make about 1/5 the milk of a cow, it also consumes only about 1/5 the feed. But 5 goats will produce less methane than 1 cow. And goat milk is more nutritionally compatible with the human body.

You can't make a pizza with goats cheese

For pizza, I'd recommend a sheep's milk cheese, like petit basque.

The point is that for goats, or cows, to produce milk they must get pregnant, and so you get a lot of calves which have no use except as food. It would be a terrible waste to just kill them, and a terrific trouble if they were left alive because the you'd simply drown in cows.


There are ways to "trick" the animals bodies into making milk. But the organic crowd doesn't like that either, since it involves giving them hormones.

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