top of page
Search

The Thirstiest Diet: Does Your Burger Use More Water Than Your Car?

  • Writer: Emanuele Bortolotto
    Emanuele Bortolotto
  • Jul 26
  • 8 min read

Updated: Sep 7



Finland, as a nation, has a profound relationship with water; it is a country of nearly 188,000 lakes, a place where water is a constant, defining presence. This watery abundance got me thinking about the water we don't see—the vast, invisible rivers of "virtual water" that flow through our global food system every single day. 🌊

We are all pretty good at conceptualizing the water we use directly. The water we drink, the water we shower in, the water we use to wash our dishes. But this visible water is just a tiny drop in the bucket of our true water consumption. The vast majority of our personal water footprint is hidden in the things we buy, and especially in the food we eat.

This led me, as an investigator of inconvenient truths, to a deeply important question. In a world of increasing droughts and water scarcity, which diet is the thirstiest? Is the lush, green world of a vegan diet as gentle on our water resources as it seems? Today, we’re going on a deep dive to find out: What’s the water footprint of a vegan diet compared to omnivores? The answer, I discovered, is truly staggering.


The Invisible Water: A Deeply Pedantic Guide to the Water Footprint


Before we can compare a steak to a sweet potato, we first need to understand what a "water footprint" actually is. It’s not just the water that was used to wash the food. It’s a comprehensive accounting of every single drop of water used in the entire production process. I found that the brilliant scientists who invented this concept, like Arjen Hoekstra, broke it down into three colors, which makes it all sound a bit like a confusing board game. 🎲

  • Green Water 💚: This is the rainwater that falls from the sky and is stored in the soil. It's the water that grows forests, grasslands, and rain-fed crops. Think of it as the "free" water, the water that nature provides.

  • Blue Water 💙: This is the water that is withdrawn from surface and groundwater sources—rivers, lakes, and aquifers. It’s the water we use for irrigation, for industry, and for our homes. This is the precious, finite water that, when overused, leads to dried-up rivers and depleted aquifers. Blue water is the most critical and contentious part of the water footprint.

  • Grey Water 🖤: This is a more abstract concept. It’s the amount of fresh water required to dilute the pollutants generated during the production process (like fertilizer runoff or animal waste) to the point where the water quality meets acceptable standards. It’s the "sorry" water, the amount needed to clean up the mess.


I was explaining this to my editor, and he just stared at me blankly for a moment before saying, "Manu, are you telling me that my morning coffee is mostly made of apology water?" Which, when you consider the pesticides and fertilizers used in some coffee production, is not an entirely inaccurate, if deeply cynical, way to put it.

The total water footprint of a food is the sum of these three colors. Understanding this is key to figuring out why some foods are so much thirstier than others.


The Thirstiest Meal on Earth: The Astonishing Water Footprint of Animal Agriculture


My investigation into the water footprint of different foods revealed one clear, undisputed, and shocking truth: raising animals for food is the most water-intensive thing humans do. It’s not even a close contest.

But why? It’s not because cows are out there taking excessively long showers. The vast, overwhelming majority of the water footprint of any animal product is not from the water the animal drinks, but from the water required to grow the enormous quantity of feed it must eat over its entire lifetime.

It's a problem of trophic levels, of basic biological inefficiency. To produce one kilogram of beef, a cow needs to eat many, many kilograms of corn, soy, and alfalfa. Each of those kilograms of feed had its own massive water footprint to grow. The animal is essentially a middleman, and a very inefficient one at that, concentrating the water footprint of all the plants it ever ate into a single piece of meat.

Let’s look at the staggering numbers, based on the groundbreaking global analysis by Mekonnen and Hoekstra.

Food Product (per kilogram)

Global Average Water Footprint (Liters)

Beef

15,415 L

Sheep/Goat Meat

8,763 L

Pork

5,988 L

Cheese

5,060 L

Chicken Meat

4,325 L

Eggs

3,265 L

Tofu

2,500 L (approx.)

Rice

2,497 L

Pulses (Beans, Lentils, etc.)

4,055 L (for dried pulses)

Wheat Bread

1,608 L

Potatoes

287 L

Vegetables (general)

322 L

Fruits (general)

962 L

The numbers are hard to even comprehend. To produce one single hamburger patty, the global average water footprint is around 2,500 liters. That is the equivalent of taking a four-hour shower. Or flushing your toilet over 400 times. For one burger. 🍔💦 The footprint of a kilogram of vegetables, by contrast, is a tiny fraction of that.

When you look at it from a "per gram of protein" perspective, the difference becomes even more stark. The water footprint per gram of protein from beef is, on average, six times larger than the footprint per gram of protein from pulses like beans and lentils.


The Almond in the Room: Acknowledging Thirsty Plants


Now, an honest investigator must also address the most common counter-argument I hear in these debates: "But what about almonds and avocados?! I heard they're destroying the planet!" 🥑

This is a valid and important point, and it adds a necessary layer of nuance to our investigation. It's true. Certain plant foods have a much higher water footprint than others. Nuts, in general, are very thirsty. A kilogram of shelled almonds requires around 16,000 liters of water to produce.

Wait a minute! That's more than beef! Case closed, right? The meat-eaters were right all along!

Not so fast. This is where we have to remember our three colors of water. The vast majority of the water footprint for beef is green water—rainwater that fell on the pastures and fields used to grow its feed. This is still an enormous use of a natural resource, but it's different from the main problem with almonds.

The issue with almonds, specifically those from California where most of the world's supply is grown, is that they have a very high blue water footprint. They require a huge amount of irrigation water, drawn from the state's severely depleted rivers and aquifers. This is a very serious environmental problem.

However, it does not give a free pass to animal products.

  • It's a Specific Problem: The almond issue is highly specific to one crop in one drought-prone region.

  • Perspective is Key: Even with their high water footprint, the overall environmental impact of almonds in terms of land use and greenhouse gas emissions is still a tiny fraction of the impact of beef or dairy.

  • Dairy's Water Footprint: And let's not forget, it takes about 1,000 liters of water to produce just one liter of cow's milk. That fortified almond milk, with its high water footprint, is still often a more sustainable choice.

The lesson here is not that all plants are perfect, but that even the thirstiest plants are often still a better choice than most animal products when you look at the total environmental picture.



Questions from the Internet: "Okay, just give me the numbers. How much water does a vegan diet actually save?"


This is the big question. My investigation into several major studies, including a 2016 study from the University of Oxford, found a remarkably consistent answer. When you compare a standard omnivorous diet to a vegetarian or vegan diet, the results are dramatic.

Switching from a standard Western diet to a nutritionally equivalent vegan diet can reduce your personal food-related water footprint by anywhere from 30% to 55%. The exact number depends on what specific foods you eat, but the direction is always the same: a massive reduction in water consumption.


Questions from the Internet: "What is the single worst food for water consumption?"


The undisputed, undefeated, heavyweight champion of water consumption is beef. Nothing else even comes close, especially when you consider its relatively low caloric return. After beef, other animal products like lamb, pork, and cheese are the next thirstiest contenders. The single most impactful thing a person can do to reduce their personal water footprint is to eat less beef.


Questions from the-Internet: "Is drinking bottled water bad for my water footprint?"


This is a great tangent. The amount of water actually in the bottle is, of course, just one liter. But that's not the whole story. You have to consider the "virtual water" needed to produce the bottle itself. My research shows that it takes around 5 to 6 liters of water to manufacture a single one-liter plastic (PET) bottle. So when you buy a bottle of water, you are actually consuming 6-7 liters of water. It's a surprisingly thirsty product. Stick to the tap if you can. 💧


Internal Link Break!


The water footprint is just one piece of the environmental puzzle, a single front in the war against planetary destruction. For the full picture, including the even more staggering impact of animal agriculture on land use and greenhouse gas emissions, you must read my full investigation: [Can Veganism Save the Planet?]


The Conclusion: It's the Cow, Not the Shower


So, after this deep and watery investigation, what is the final verdict? What’s the water footprint of a vegan diet compared to omnivores?

My conclusion is that the difference is not just a small leak; it's a deluge. A diet that includes meat, dairy, and eggs has a dramatically, almost absurdly, larger water footprint than a diet built on plants. The scientific data is not ambiguous.

In a world facing increasing droughts, desertification, and conflicts over water resources, the choices we make at the supermarket have a very real and very powerful impact that ripples across the globe. We often think that the best way to save water is to take shorter showers or turn off the tap when we brush our teeth. And those are good things to do. But my investigation has made it clear that those are tiny drops in the bucket. The real water conservation happens not in your bathroom, but on your dinner plate.

It turns out the thirstiest thing on the planet isn't a desert. It’s a steak. 🏜️

Of course, for most people, the motivation to go vegan isn't about water; it's about animals. To understand the complex philosophy that started it all, check out my guide: [What Is Ethical Veganism?].


Sources


Recent Posts

See All

Comments

© 2020 Copyright Emanuele Bortolotto

bottom of page