It'll be hard, but we can feed the world with plant protein

It'll be hard, but we can feed the world with plant protein
Legumes such as chickpeas are high in protein. Credit: lchunt/Flickr, CC BY-NC-SA

A U.N. report released last week found a quarter of the world's carbon emissions come from the food chain, particularly meat farming. This has prompted calls to sharply reduce emissions from agriculture and to feed the world on plant protein.

Can we feed a growing without increasing the amount of farmland? It's tough, but certainly possible.

There might still be a place for meat animals in the many parts of the world unsuitable for growing crops. But governments around the world must turn away from heavily subsided but protein-poor cereals, and aggressively pursue production.

How much land do we have to work with?

In 1960, there was one-third of a hectare of farmland per person on the planet. By 2050 that will have fallen to 0.14 hectares, according to research at Michigan State University. This trend is a consequence of increasing population and urban encroachment. Most cities were established on close to water supplies, and urban expansion continues to consume significant productive land.

About one-third of cereals produced globally now are fed to animals (mainly in Europe and North America, although this is changing across the developing world as incomes rise and demand for meat increases).

Converting these areas to food production would significantly improve the amount of available to people. Research has estimated some 16% of edible crops are diverted to biofuel production, and redistribution of these proteins and calories to people would also help immensely. However, biofuels are renewable and less polluting than fossil fuels, and therefore have potential to offset carbon emissions.

Nevertheless, we cannot completely discount animal protein. Around half the world's land surface is rangelands, covering arid, semi-arid, and dry sub-humid climates. These areas are unsuitable for cropping, and many cattle and sheep are raised there.

They have traditionally been used for extensive pastoralism, and the meat produced there is more expensive than meat from feedlots, because of slower growth rates and higher transport costs. However, people are increasingly concerned with the provenance of their food, and may well be willing to pay more for single-origin food produced sustainably.

Beans, glorious beans

Next we must consider what crops we grow on this land. Continuing to grow maize and other low-protein cereal crops on land formerly used to provide feed or biofuel is unlikely to provide enough plant-based protein for an expanding population.

It'll be hard, but we can feed the world with plant protein
Legumes currently only make up 10% of the world’s crops. Credit: whologwhy/Flickr, CC BY

There must be an increase in the production of leguminous crops, such as peas and beans, that fix their own nitrogen and that provide nutritious grains high in protein. The grain of legumes is 20-30% protein, compared with 10% in maize, which is the most extensively grown cereal crop used for animal feed.

However, lifting the yield of legumes is a significant challenge as expenditure on the genetic improvement of these crops (except possibly soybeans) has been dwarfed by that spent on the major cereals. It is essential this component of the future global farming system becomes more productive and sustainable.

In rotation with cereals, legumes enhance the productivity of the entire farming system. According to research from Pulse Breeding Australia, legumes should make up 25% of global crops. We are far from achieving this target, with just 10% of cropping dedicated to legumes.

Unlike cereals, legumes are harder to grow and require more skilled management. Legumes are generally more susceptible to diseases, including viruses and insect pests, and are significantly impacted by temperature extremes and drought. As global warming increases, the difficulties associated with producing legumes are likely also to rise. More resources, therefore, will have to be invested in researching legume cultivation.

We can't see the future

There are plenty of knock-on consequences of any major changes to our . Phasing out feedlots for animal farming, for example, will reduce the effluent that often contaminates waterways and causes nutrient toxicity in nearby fields. This will increase the price of grass-fed meat.

The lower yields of legume crops, combined with government support for cereals in many countries, currently strangle their production. To increase crops, farmers will need incentives until increased demand can support higher prices. We must be prepared to pay more for vegetable protein, and vegan options may no longer be among the less expensive options on restaurant menus.

The current move to meat-like vegetable protein products is also unlikely to gain much traction in the longer term as the cost of processing these materials will reduce their appeal.

The transition to a world fed on vegetable protein will be made against a dwindling amount of land per person and an increasingly hostile farming environment in many areas.

Increasing temperatures will change disease patterns and traditional crops may no longer be viable in some regions. Governments will also need to reassess policies that favor the production of higher-yielding but protein-poor .

Feeding the world on plant-based is an incredibly complex proposition, with many variables we cannot accurately predict. But this should not stop us trying; it is certain that whatever the difficulties, they will be greatly magnified in a significantly warmer world.

There is much complexity around the notion that we can feed the world on plant-based proteins and many variables we cannot yet accurately predict. However, this should not stop use from trying to achieve this outcome in whole or in part.


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Legumes for a sustainable farming future

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Aug 16, 2019
The proteins in legumes aren't directly comparable with proteins obtained from animals, because they are poorly digested by humans.

The main problem is the lectins in legumes:
https://en.wikipe...e_lectin
The exact function of the legume lectins in vivo is unknown but they are probably involved in the defense of plants against predators.
https://en.wikipe...i/Lectin
Lectins are considered a major family of protein antinutrients, which are specific sugar-binding proteins exhibiting reversible carbohydrate-binding activities.[23] Lectins are similar to antibodies in their ability to agglutinate red blood cells.[24]

Many legume seeds have been proven to contain high lectin activity, termed hemagglutination.


Basically, why beans give you wind. They bind to other nutrients and prevent them from absorbing in the gut, passing them through to the lower intestines where bacteria eat them and produce gas. Same effect as in lactose intolerance.

Aug 16, 2019
The other issue is that you still don't get enough proteins from plant based foods for a balanced diet.

A good diet consists of about 1/3 oils or fats, 1/3 carbohydrates, and 1/3 proteins, give or take a little. The issue is that if you want to get your protein calories from beans that contain around 20% edible proteins, then you need to eat more than half your calories in beans.

Minimizing your protein intake, you could eat a more varied diet, but you'd be borderline protein deficient. What it means is, you have to separate the proteins out of legumes and throw the rest away so you can eat something else instead - but this is inefficient.

If only there was a way to turn the unwanted carbohydrates in legumes into proteins... like, feeding it through some process that re-forms it into a high-protein foodstuff very much like meat...

Aug 16, 2019
'Can we feed a growing global population without increasing the amount of farmland? It's tough, but certainly possible."

-Well sure, until a few gens later when there are again too many people and your resources are again depleted. Ask malthus.

Want to solve world hunger? Get rid of the main cause of overpopulation - religion.

Aug 16, 2019
Fascinating isn't it?
The AGW Cult incessantly braying that we are in a crisis loop of food production and climate. Yet, they support 16% of our food being diverted to bio-fuels just to sustain the deceit of their dogma.

Gobble up, my hungry, ignorant Chicken Littles.

Aug 16, 2019
life under communism in the new green future

Aug 17, 2019
I just watched Endgame and I had a thread-related question or 2...

Thanos killed off half of all life on earth. Then, 5 years later, the avengers brought it all back. I suppose wild animals would have relatively few problems getting food, but human food needs to be cultivated and nobody had been doing that for the 3-4 billion who were suddenly standing around listening to their bellies growl.

What to do?

Perhaps I should post this dilemma in the 'cannibalism' thread.

Aug 17, 2019
Let's start by feeding our prison populations with a diet high in soy protein. Not only is it cheaper than meat and chicken but the phytoestrogens in soy might possibly lower the testosterone in the male prison population helping them with a lot of their issues. If its good enough for people not in prison, its good enough for inmates.

Aug 18, 2019
Fascinating isn't it?
The AGW Cult incessantly braying that we are in a crisis loop of food production and climate. Yet, they support 16% of our food being diverted to bio-fuels just to sustain the deceit of their dogma.

Gobble up, my hungry, ignorant Chicken Littles.

Those 2 Peas struggling to make sense of the Overwhelming evidence for Human Induced Climate Change... Again ? ? No monkey nuts Empirical Evidence and Dogma are 2 different things, did you still not ask your daddy ? Or is he tired of telling you the same thing over and over again, i'm not its always fun to see you stupefy yourself on a daily basis :D

Aug 19, 2019
life under communism in the new green future
Well, communism does shrink pops by extreme economic austerity, shipping the middle class off to gulag, one child per family laws, or simple mass starvation like 5 year plans or holodomor. Or even directly like Khmer rouge or 700M+ ABORTIONS and counting.

Sure these things might be bad but sometimes they may be necessary, ya know?

And the weeds are thriving around Chernobyl, aren't they?

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