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"Avocados and almonds use a lot of water."
it's a selective comparison. Some plant foods, such as almonds and other nuts, do use a lot of water. But the fair comparison is per nutrient and across the whole diet. According to Poore and Nemecek's data, cow's milk uses about 628 liters of water per liter, and soy milk 28. Tofu uses about 93 liters per 100 grams of protein; beef, about 728; cheese, more than 2,500. A well-chosen plant diet uses less water, land and emissions.
Short answer
Some plant crops use a lot of water, and it's good to choose them carefully. But the fair comparison is per nutrient and per diet. According to Poore and Nemecek's data, a liter of cow's milk uses about 628 liters of water, and a liter of soy milk 28. Per 100 grams of protein, tofu uses about 93 liters, peas 178, beef 728 and cheese more than 2,500. No one needs almonds to be vegan.
For children
All foods need water to grow. Some plants, like almonds, need quite a lot. But to make cow's milk or cheese, the cow has to be given water and food for a long time, and that uses even more. Soy milk, for example, uses much less water than cow's milk.
"If cow's milk uses more water than soy milk, why would plant milk be the problem?"
Como pode aparecer
"Almond milk dries up rivers."
"Avocados use a lot of water."
"Quinoa took food from people in the Andes."
"Vegans are destroying the planet with avocados."
"Some plant crops have a high water footprint."
"Vegans' soy is destroying the Amazon." (which is H1)
The strongest version
"Almond milk dries up rivers. Quinoa took food from people in the Andes."
Strongest version (steelman):
- P1Some foods popular among vegans, such as almonds and avocados, use a lot of water and are sometimes grown in dry regions.
- P2Producing these foods can cause environmental and social harm.
- CSo the vegan diet isn't environmentally superior.
P1 and P2 are true in some cases. The problem lies in the conclusion: it compares isolated foods, not diets, and ignores that animal products are among those that use the most water per nutrient.
The argument is valid for the foods cited. It fails as a conclusion about diets.
Full answer
- a
Reconstruction and diagnosis
The argument picks plant examples and leaves out animal ones:
Food Water per 100 g of protein (liters) Tofu About 93 Peas About 178 Other pulses About 204 Chicken About 381 Beef (beef herd) About 728 Cow's milk About 1,904 Nuts About 2,531 Cheese About 2,539 - b
Where the argument breaks
1. It's a selective comparison.
The examples chosen are precisely the plants that use the most water. The main plant protein sources, such as tofu, peas and beans, use far less water than most animal products.
2. Cow's milk uses much more water than soy milk.
Per liter, about 628 against 28 liters. Even plant drinks that need more water, such as almond milk, usually compare favorably with cow's milk on land and emissions.
3. The diet is what matters.
Plant diets use less land, emit less and, in general, use less water than diets with meat and dairy.
4. No one needs avocados or almonds.
They're options, not the basis of a vegan diet. Beans, rice, lentils and vegetables are low-impact plants.
5. The quinoa story was exaggerated.
The idea that demand for quinoa harmed Andean producers was disputed by later studies, which found rising household welfare in producing regions while prices were high.
- c
Data and sources
Source What it says Note Our World in Data, water per 100 g of protein Tofu about 93 L; peas 178; beef 728; milk 1,904; nuts 2,531; cheese 2,539 Based on Poore and Nemecek, 2018 Our World in Data, water per kilogram of product Cow's milk about 628 L per liter; soy milk about 28 L Based on Poore and Nemecek, 2018 Bellemare, Fajardo-Gonzalez and Gitter, 2018, *World Development* As quinoa prices rose in Peru, household welfare increased in producing regions, and negative effects were small An 11-year household survey; checked from the abstract - d
The strongest counter-reply: nuts are an important part of a vegan diet
The most serious version points out that nuts, which use a lot of water, are an important source of nutrients in vegan diets.
- e
Why the counter-reply doesn't reach the conclusion
The quantities eaten are small.
No one eats nuts in the amounts people eat meat or cheese.
There are alternatives.
Peanuts, seeds and legumes use far less water.
The diet as a whole still comes out ahead.
Even with nuts, a vegan diet uses less land and emits less.
- f
Back to the moral question
The water footprint of food is an important environmental question, and it deserves attention in every diet. But it doesn't answer the question about the animals: to get meat, milk and eggs, they are raised and killed. If it's possible to live well on plants that use less water, what justifies that cost?
Reasoning errors
Epistemological
Does the evidence support it?
Cherry picking
Logical
Is the form valid?
Unequal comparison
Tu quoque
Biases
Confirmation bias
Accepts the news story that blames vegans
General literature on confirmation bias
Extrapolations
The principle being tested is: "if some food in a diet has a high impact, the whole diet is worse".
If it applied to…Diets with meatTap to see
They'd be worse, because they include cheese and beef
The data confirm it
If it applied to…Diets with coffeeTap to see
They'd be worse, because coffee uses a lot of water
No one concludes this
If it applied to…Vegan dietsTap to see
They'd be worse because of almonds
The whole shows the opposite
Contradictions
Which uses much more water than soy milk.
One of the foods that uses the most water per unit of protein.
Which aren't exclusive to vegans.
What the argument gets right
What is true
It's true that some plant foods use a lot of water and that growing them in dry regions can cause problems. Choosing lower-impact foods is part of responsible eating, and vegans aren't exempt from that attention.
But
But the fair comparison shows that the main plant protein sources use far less water than meat and dairy. If the concern is water, a plant diet is the best choice.
Connections
Usually comes before
Usually comes after