This Is How Much Water It Takes To Make Your Favorite Foods

Extensive drought has Californians thinking twice about running the tap while brushing their teeth or taking that 20-minute shower. But what some people don't realize is that a huge portion of our water footprint is "hidden," meaning it's used for the things we eat or wear, and for the energy we use. Globally, agricultural production accounts for 92 percent of our water footprint. In the United States, meat consumption alone accounts for a whopping 30 percent of our water footprint. 

So exactly how much water do the foods you eat require? Which food would win in a water use showdown? We've got the answers below, along with some helpful hints about reducing the water footprint of your diet. 

All data come from Water Footprint Network's website and reports on the global average water footprint of different foods. All winners are based on the gallons of water needed to produce a pound of each item or a gallon of each drink. 

One thing I learned a while back is that agriculture uses a lot of water, so drinking a liter of plain water uses less water than drinking a liter of just about any other beverage, other things being equal.  But this is also true of any other foods, not just beverages.  This makes sense, if you think about it, since humans mostly eat other lifeforms, and all life on our planet requires water to live, and just like us, often needs this water on a somewhat regular basis.

Here are some of the numbers from the article:

Tea vs. Coffee

Winner: Tea is the winner at 108 gallons of water per gallon of brewed tea. Coffee requires almost 10 times as much water, using 1,056 gallons of water per gallon of brewed coffee. 

Beef vs. Chicken

Winner: Chicken at 518 gallons of water per pound. Beef requires the most water, at 1,847 gal./lb., followed by sheep at 1,248 gal./lb. and pork at 718 gal./lb. If you're going to eat meat, go with chicken. Better yet try eggs, which take 395 gal./lb., or plant based protein. For dairy products, cheese and butter take more than milk at 381 gal./lb. and 665 gal./lb. respectively. Milk by itself uses only 122 gallons of water per pound.

Tofu vs. Lentils

Winner: Tofu at 302 gal./lb. It takes 704 gallons of water to produce one pound of lentils. Chickpeas require less than lentils at 501 gal./lb., and soybeans require less than the more processed tofu, at 257 gal./lb. All of these options are better than eating beef, sheep or pork. 

Some will argue that the measurement of gallons per pound isn't fair -- we should consider water consumed per gram of protein. In this case, pulses (including beans, lentils, peas, etc.) win out at 5 gallons per gram of protein, followed by eggs at 7.7 gal./gram, milk at 8.2 gal./gram, and chicken at 9 gal./gram. The numbers only go up from there, with beef topping the scale, requiring 29.6 gallons of water per gram of protein.

Oats vs. Potatoes 

Winner: Unprocessed potatoes at 34 gal./lb. It takes 290 gallons of water to produce one pound of rolled or flaked oats. Sweet potatoes also take less water, using 46 gal./lb., while unprocessed corn requires 146 gal./lb

I haven't extensively checked the sources on this, but it does somewhat match up with what I've seen in other places, and I can also think of reasons why some of these might require more water than others.  

One thing to note is that while they do talk a bit about different types of comparisons like amount of water per lb of food as well as amount of water per gram of protein, they don't talk much about amount of water per serving (except to mention it in passing towards the end), which is especially relevant when discussing  oil since 1 lb of oil is quite a lot more servings when compared with a lot of the other items on this list. At least it is for me (though I also think this is another good reason to avoid deep frying, which uses a lot of oil relative to other cooking methods).

There are, of course, other considerations besides water, like land use and impact on climate change, but water requirements for food are certainly one important piece to understanding the environmental impact of modern agriculture.

I like that they link to more detailed sources throughout the article, including the links in the above excerpt and the ones here at the end:

Of course, these measurements are by pound, and we think it's unlikely you would consume the same weight in ketchup as you would whole tomatoes. The Water Footprint Network also suggests choosing high water intensity products that are grown or produced in areas that do not have water scarcity problems, if making changes to your diet proves difficult.

Curious about foods we didn't cover? Click here to view the full reports on crops and animal products.

One thing I do kind of take issue with is the focus on an individual's 'water footprint', which is the same idea as a 'carbon footprint', an idea made up directly by oil companies to try to divert attention away from the larger systemic issues at hand and reduce this all to individual decisions.  The truth is more complicated, and while I think it is important to acknowledge that we are not somehow entirely separate from the systems we all depend on for survival and that our choices within that system are relevant, the system itself also needs to change in ways our individual choices alone cannot influence.