Food waste: The biggest loss could be what you choose to put in your mouth

Credit: CC0 Public Domain

About a third of the food produced for human consumption is estimated to be lost or wasted globally. But the biggest waste, which is not included in this estimate, may be through dietary choices that result in the squandering of environmental resources. In a study published in the Proceedings of the National Academy of Sciences (PNAS), researchers at the Weizmann Institute of Science and their colleagues have now found a novel way to define and quantify this second type of wastage. The scientists have called it "opportunity food loss," a term inspired by the "opportunity cost" concept in economics, which refers to the cost of choosing a particular alternative over better options.

Opportunity loss stems from using to produce animal-based food instead of nutritionally comparable plant-based alternatives. The researchers report that in the United States alone, avoiding opportunity food loss - that is, replacing all animal-based items with edible crops for - would add enough food to feed 350 million additional people, or more than the total US population, with the same land resources. "Our analysis has shown that favoring a plant-based diet can potentially yield more food than eliminating all the conventionally defined causes of food loss," says lead author Dr. Alon Shepon, who worked in the lab of Prof. Ron Milo in the Plant and Environmental Sciences Department. The Weizmann researchers collaborated with Prof. Gidon Eshel of Bard College and Dr. Elad Noor of ETZ Zürich.

The scientists compared the resources needed to produce five major categories of animal-based food - beef, pork, dairy, poultry and eggs - with the resources required to grow edible crops of similar nutritional value in terms of protein, calorie and micronutrients. They found that plant-based replacements could produce two- to 20-fold more protein per acre.

The most dramatic results were obtained for beef. The researchers compared it with a mix of crops - soya, potatoes, cane sugar, peanuts and garlic - that deliver a similar nutritional profile when taken together in the right proportions. The land area that could produce 100 grams of protein from these crops would yield only 4 grams of edible protein from beef. In other words, using agricultural land for producing beef instead of replacement crops results in an opportunity food loss of 96 grams - that is, a loss of 96% - per unit of land. This means that the potential gain from diverting agricultural land from beef to plant-based foods for human consumption would be enormous.

The estimated losses from failing to replace other animal-based foods with nutritionally similar crops were also huge: 90% for pork, 75% for dairy, 50% for poultry and 40% for eggs - higher than all conventional food losses combined. "Opportunity food loss must be taken into account if we want to make enhancing global food security," Milo says.

Prof. Ron Milo's research is supported by the Mary and Tom Beck - Canadian Center for Alternative Energy Research, which he heads; the Zuckerman STEM Leadership Program; Dana and Yossie Hollander; and the Larson Charitable Foundation. Prof. Milo is the incumbent of the Charles and Louise Gartner Professorial Chair.

The Weizmann Institute of Science in Rehovot, Israel, is one of the world's top-ranking multidisciplinary research institutions. Noted for its wide-ranging exploration of the natural and exact sciences, the Institute is home to scientists, students, technicians and supporting staff. Institute research efforts include the search for new ways of fighting disease and hunger, examining leading questions in mathematics and computer science, probing the physics of matter and the universe, creating novel materials and developing new strategies for protecting the environment.

Explore further

Research reveals the comparative environmental costs of livestock-based foods

More information: Alon Shepon el al., "The opportunity cost of animal based diets exceeds all food losses," PNAS (2018).
Citation: Food waste: The biggest loss could be what you choose to put in your mouth (2018, March 26) retrieved 19 August 2019 from
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

Mar 26, 2018
And now the war on meat.... The Vegans Strike Back.

Mar 26, 2018
It is amazing that so few vegans hold so much power. They have been killing people for 50 years now by pushing high carb low animal fat diets as heart healthy.

Mar 26, 2018
A 2016 systematic review found that there was no effect of vegan diets overall on all-cause mortality, cancer mortality, cerebrovascular disease or cardiovascular-disease-related mortality. The effects also disappeared when specific cancers were analysed.

Mar 26, 2018
Out of the approximately 13.772 billion years that the universe has existed, not considering the time that it has left, I am allowed perhaps 80 years. I intend to savor that infinitesimal moment in time by doing and eating whatever the hell I am programmed, genetically or otherwise, to enjoy.

So all you twits who are apparently programmed, genetically or otherwise, to boss other people around, can take a flying leap.

Mar 27, 2018
Lot of emotion here.

You cannot dispute the science, so I suppose emotion is what you have left.

Mar 27, 2018
Dan42day, out of the entire history of the universe, the human species is the first thing to occur that can look at its own actions, form a model of how that actions' consequences effect others, and direct itself to change its behavior on a global scale.

If you want to throw away that ability because meat is tasty, then hopefully you're an outlier.

More self-serving, learning to enjoy a few different things isn't going to hurt your brain, and it'll give you something to talk to others about. And nobody's saying you have to jump right to level five veganism; a steak every week or two isn't out of the question.

Mar 27, 2018
PTTG, the assumption that the human (your) species is the first salient thing in the entire history of the universe only highlights the arrogance with which you preach your dogma. You are free to eat whatever you like, please extend the same courtesy to the rest of us.

Mar 27, 2018
A little less meat wouldn't hurt any of us. Humans are omnivores and able to live healthy within a large range of diets. i think no one would argue against the fact that current (western) diets contain an overabundance of refined sugars and meats.

The article isn't about whether eating meat is healthy or not. It's about whether having such a high meat content in out diets is sensible given the larger picture (viz: climate change, limited arable land, overpopulation)

Mar 27, 2018
Anti the problem is that in the past people were told to replace meat and animal fats with breads, pasta, rice and potatoes. This was claimed to be a Heart Healthy Diet. This group of carbs are digested very quickly and spike blood sugar as much if not more than cane sugar and corn syrup. When combined with any fat or oil they become even more deadly since the carbs are processed for energy while the fats are stored as body fat and not turned into energy. The rise in diabetes and heart disease is directly attributable to this diet recommendation. The only way to utilize body fat as a source of energy without suffering huge hunger pains is to not eat these carbs.

Mar 27, 2018
I am allowed perhaps 80 years. I intend to savor that infinitesimal moment in time by doing and eating whatever the hell I am programmed, genetically or otherwise, to enjoy
By savor do you mean waddling around in a slovenly shell of fat, knowing subconsciously that in your decrepit and sickly state you are unable to protect yourself from assault, accident, and natural disaster?

By enjoy do you mean being unable to feel the intense pleasure, the sense of freedom, confidence and well-being that comes from hard exercise... or spending the last 20 years of your life in and out of hospitals, suffering the miserable effects of stroke, heart disease, diabetes, Alzheimer's and Parkinson's?

Are you so sure you know what the words 'savor' and 'enjoy' really mean?

Aren't you curious to find out before you lose that chance forever?

Mar 27, 2018
Even then beef-eaters will continue to eat the beef, and are determined to destroy the planet. They always have illogical counter arguments...

Mar 27, 2018
The article makes an excellent point. Too many people talk up the horrors of climate change and the continued destruction of the environment, but eagerly consume foods that contribute to both. And it's not just about carnivores VS. vegans. Many plant products don't do the planet any favors either. Each almond you eat required a gallon of water. The blueberries at the store where flown in from Chilie. The environmental costs of our foods should be more transparent. And more people should seek this information. If so, I believe many more people would make better choices.
And please don't get us started on the future healthcare costs we all will bear. :-)

Mar 27, 2018
I blame the dietary wars on the loss of religion. People need a new obsession, a new sense of possessing the "Truth", a new reason for berating and oppressing others for not joining them on their self-defined moral high ground.
Health has more to do with exercise than than diet anyway - for example, the Inuit, who for thousands of years lived on a very high fat/meat diet, but of course had to hunt it down across the ice with sharp sticks; consequently maintaining good health.
And if beef has the highest environmental cost, it ought to be reflected in the market price. In general, the environmental costs of various foods are entirely lost in the huge network of competing taxes and subsidies, direct and indirect.

Mar 27, 2018
Ah Soylent Green is the only conscientious answer to man's criminal hunger. Perhaps some sort of spread made from purified waste treatment plant sludge would make a nice flavorful topping.

The guilt of the old organized religions has been replace by to guilt of the new organized religion, AGW.

Mar 27, 2018
OK let's try that last sentence in actual English.

The guilt of the old organized religions has been replaced by the guilt of the new organized religion, AGW.

Mar 28, 2018
"Moderation in everything."

A meat eater myself, I try to balance with big helpings of veggies and carbs. It is my selfish choice, for good and bad.

From the histrionic comments, you'd think that the Nanny State was running amuck. Ripping the fries and burgers out of the palsied hands of the persecuted consumers of meat by-products.

The ignored reality of voracious appetites is that this entire controversy is a sham. The real problem is our instinctive addiction to salt and sugar. Of which enormous quantities are consumed to overwhelm the subtle (boring) natural flavors of our food.

Aside from the basic tastes such as sweet or salty. What we call tastes are actually smells. Produced in our food by enzymes. Ripening fruit and aging meat. To attract flies.

Additional complexity of flavor/smells are produced by bacteria and fungi micro-organisms.

If the above hysterics were honest with themselves? They would admit their real fear is losing their ketchup.

Mar 28, 2018
The logic I use is more personal than environmental: if you expend a lot of physical energy and have very little time to eat to eat, or don't like eating, then of course, being a carnivor is ideal. Meals of meat are smaller, packed with protein and calories, and take little time (or chewing) to consume. But if you live a lifestyle requiring less physical energy, have plenty of time to eat, and actually enjoy the act of eating and tasting a wide variety of flavors (both subtle and intense), then you will find a vegan diet to be very enjoyable.

For example: a proper salad (with no dressing) will provide a new taste experience with every bite. A meal of meat or a salad with oil dressing tastes fine for a few bites, but once your mouth is coated with fats, the taste profile varies very little. And great taste does not need to be brash. That would be like saying "I only like art with bright colors." Enjoying subtly is an act of learned sophistication, no matter the art form.

Mar 28, 2018
But I am not saying that you should become vegan. It takes time. It took me three years to go from omnivore to gluten-free vegan. IMO, too many people jump right in and then say they hated it. Duh. Changing your taste palette requires patience and a genuine openness to experiencing new things, new sensations, and perhaps most importantly, new comfort foods. But it can be done. I for one have found it well worth the adventure.

Mar 28, 2018
Mayday, I applaud your persistence and patience at controlling your own appetites. Leading by example.

I wish I had the strength of character to give up the small but regular consumption of meat.

However I must correct the conclusions in your first comment.

The predatory life is for the lazy gambler. The herbivore /vegan has to be methodical gathering food. And wary!

The meat-eaters are either hunting or dozing as they digest their last meal. Or, to husband their remaining energy until something edible wanders by.

The herbivore /vegan is constantly grazing.

Humans and canines and some predatory whales are long-distance hunters. Most of the others are spasmodic, striking from ambush. And in general most attempts to catch a meal fail for one reason or another.

No matter what the 'edited' nature videos are showing. This has become a big controversy among nature videographers. The public thinks that what they are being shown is accurate to real life.

Mar 28, 2018
rrw, thanks for the correction, but I wasn't referring to carni vs vegan in the evolutionary sense, but in the modern western lifestyle sense.
Many people eat too many calories and too much protien for their lifestyle. A plant based diet that avoids most processed foods and sugars is perfect if eating is your stress relief. Done right, you can eat all you want. And you don't need meat to get protien, or dairy to get calcium. That's just marketing.
And it sure doesn't take much strength to eat well as a vegan. I just had a great Indian meal that was rich and satisfying in every way. And I could eat my fill. The patience comes from allowing your tastes to develop in new directions and in giving up old habits and ideas. We all crave fat, salt, and sweet. And the food industry provides. But the fact is, there are many, many other things that actually taste better. Look at your spice rack. It's all vegan, except for the bacon bits! :-)

Mar 29, 2018
Mayday your diet seems to be working for you, great. I would like to know how much of your diet consists of high glycemic index carbs like breads, pastas, rice and white potatoes. They, IMHO, cause cravings and weight gain.


Mar 31, 2018
MR, I'm gluten-free, so very little breads or pastas. And even though the gluten-free versions are getting much better, they are unfortunately still made mostly with simple carbs, so I use sparingly. I enjoy rice, but eat less and less due to the heavy metals rice is so great at leaching from the soil. But I do like potatoes of all kinds. I'm not overweight. I run or workout daily. And am building muscle.

Mar 31, 2018
Don't get me wrong. By "eat all you want," I don't mean eat anything you want as long as it doesn't have eyes! You still have to use your brain. Being vegan in no way guarantees good health. You still have to make smart choices. Last point to further the thrust of the article: IMO the solution lies in encouraging people to step away from habit and live a bit more adventurously, at least in the culinary side of life.

Mar 31, 2018
Mayday I am a big fan of the Ketogenic diet which could be vegan if desired. This diet shuns high glycemic index carbs like sugar, breads, pasta, potatoes and rice. In theory these carbs create weight gain, cravings and large blood sugar swings. Does your diet include a high or low % of these carbs?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more