Can we grow enough crops to feed all people on Earth?

Vegetarianism is heavily promoted. But let’s say all people on Earth stop eating animal products. Can we grow enough crops so all people on the Earth are provided with enough healthy, nutritious food?

The question is of course very theoretical, but without discussing future possibilities to cultivate deserts and oceans, is there enough space to grow enough crops?

Answer:

This question is a very contentious one as it relies upon a lot of variables that are largely poorly understood.

The first part is arable land mass. Currently animal production is focussed on either high value grazing areas or low value extensive areas. Extensive grazing areas cannot be cropped. That area of production would have to be made up by increased crop production in other areas. 56% of Australia is extensive agriculture, worldwide it is ~5,000,000,000 hectares. That is a large amount of low production land to make up for.

Simply put, we can increase food availability (in terms of calories, protein and critical nutrients) by shifting crop production away from livestock feed, bioenergy crops and other non-food applications….. But even small changes in diet (for example, shifting grain-fed beef consumption to poultry, pork or pasture-fed beef) and bioenergy policy (for example, not using food crops as biofuel feedstocks) could enhance food availability and reduce the environmental impacts of agriculture.

Also, the areas quoted vary so much, because the figures are not fully understood. Cropping land is rarely cropped every year, instead rotated or rested at intervals, dependant upon crop type, soil type and amount of water/rainfall. Some countries just don’t have accurate records.

The second part is feed conversion. There are methods, such as mixed enterprise systems (crops plus grazing) and of course feedlotting that use grain feeding. The feedlotting is what people refer to the most, not understanding that cattle have a much higher energy conversion rate for vegetable matter than humans (being ruminants) and are not regularly fed for their entire lives. Thus grazing remains a large part of production.

Humans also preferentially eat higher protein foods like meat (see rise in meat demands from Asia with increasing wealth). This is because it is more calorically and nutritionally dense as a food, which is linked to satiety.

The third part is grain types. Most grains that are fed to animals are what is referred to in the grains industry as “feed grains”. These are generally lower quality grains that are unsuitable for human food production. Some of the grains used cannot be eaten by humans (e.g. lupins have high alkaloid levels that give both a bitter taste and become toxic when consumed regularly). Obviously the category of feed grain varies from “could be used” through to “cannot be used” for humans. This is once again a shorfall in the production required to replace meat in the diet. Remembering that feed crops are often grown where human crops cannot be grown, or not grown regularly (e.g. see wheat classes and agronomy).

Conclusion: These factors combine to create quite a different picture than what is normally presented in the “can we grow enough crops to replace meat eating” discussion. There would be less land available for cropping than is available for producing a mixed diet. There would be crops produced that would not be suitable for human consumption. We would also need slightly higher production or quality of crops to make up the energy conversion gap. This all makes for a large hole in the argument. There is nothing wrong with a vegetarian diet, nor an omnivorous one for that matter, but the environmental argument is not black and white and cannot be used as grounds for switching diets.

References:

Info on ME and DE for humans: http://fao.org/DOCREP/006/Y5022E/y5022e04.htm

This paper covers come of the conversion ratios for different animals that are grain fed (Cattle 7:1, Pigs 4:1, Chicken 2:1): http://ncbi.nlm.nih.gov/pmc/articles/PMC1240832

Another reference for the protein claims:http://sciencedirect.com/science/article/pii/S0301622699000196

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Guide to becoming an omnivore

The internet is filled with guides on how to go vegetarian, and increasingly how to go vegan. Of course the reality of these diet changes is that at some stage vegans and vegetarians are going to have to come back to eating meat, as they discover they lack energy, are anemic and their B12 and calcium levels require them to eat real food.

In an effort to help my malnourished friends before their bones shatter, I thought I would put together this quick guide to becoming an omnivore.

It isn’t as easy as just starting to eat real food again. If it were that easy, vegans would be jumping back on a normal diet all the time. The problem is that the human digestive tract changes so that your body doesn’t starve without meat in the diet. As a result it stops making the digestive enzymes that help you digest meat. Changing back to a meat diet would then mean there is a shortfall in pancreatic secretions required to digest the meat in the short-term. The changed flora in the gut would also be affected. The “sick” feeling is just your body getting used to eating properly again.

Step 1:
Go to your local butcher and purchase meat.

Step 2:
Start off small. The longer you have been unhealthy the smaller the amount of meat you want to start eating to become healthy again. Remember, you are restarting your body, so you need to be consistent and gradual so that you can adapt.

Step 3:
Increase the portion of meat in the diet gradually until you are eating normally again. This will take time, as pointed out. The end goal is to avoid all the problems of not eating meat, so stick at it.

Step 4:
Make sure you are still eating your vegetables, they make a great side dish to meat.

Step 5:
Congratulations on becoming normal again. As an omnivore you are now able to keep up with the kids, won’t have the nutrient deficiencies, will be eating complete protein sources with a good balance of amino acids and will have lowered that osteoporosis risk.

FAQ:

How soon should I make the change to eating meat again?
ASAP.

Will I be healthier as an omnivore?
As long as you eat right (meat+vegetables+fruit+cereals = right) without going all Hurley on the food you will be much healthier.

But I heard meat gives you cancer?
And I heard Elvis is still alive. Most foods contain carcinogens, that’s why you are meant to eat a balanced diet and not get fat. All of the studies that claim you will die of cancer from eating meat are lying, as they forgot to mention you also have to be inactive, fat, not eating vegetables, smoking and drinking like a fish as well.

Will I be sexier eating meat?
There is nothing sexy about salad.

But won’t I be hurting animals?
No. Animals like sheep and cattle have been bred for thousands of years to enjoy being your food. They even try to eat as much garnish as possible to make themselves tastier.

But aren’t animals farting too much for the environment?
Animals fart and burp, that’s natural. Digging up coal, oil and gas to burn for energy is damaging the environment. Plus animals are cuter and friendlier than oil executives.