Know Food's Water Footprint?

According to calculations by WaterFootprint.org a pound of tomatoes on average requires 22 gallons of water to grow.

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Compared to other vegetables, leafy greens take much less water to grow that other foods -- in the case of cabbage, 24 gallons per pound. If you want to reduce the water footprint of your diet, both lettuce and cabbage are great vegetables to eat more of.

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Yup, oranges have a comparatively low water footprint: 55 gallons per pound on average. Apples are next with 83 gal/pound, then peaches or nectarines at 143 gallons; mangoes top this list at 190 gallons.

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OK, so you know it's not peaches from the previous answer, as mangos beat them out there, but from this selection avocados rank the highest -- with a water footprint of 220 gallons per pound.

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Though tofu has a higher water footprint that other vegetable-based foods, as a protein source it has nearly one-quarter the water footprint of the lowest animal-based protein source (raised on land), chicken.

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If animal-based foods have a much higher water footprint than vegetables, grains and fruits, then beef is the absolute worst. (I'm not going to tell you the water footprint just yet; it's the next question.) But pork's average is 1630 gallons per pound; cheese requires 896 gallons; chicken is the lowest at 815 gallons.

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This is a bit of trick question: The amount of water required to produce a pound of beef varies widely depending on region, whether it's grass-fed or raised in a feedlot. It also varies widely depending on whose reporting it. 3750 gallons per pound is right in the middle of most people's water footprint calculations.

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I'm one of those rare people who likes both tea and coffee -- they each certainly have their virtues -- but when it comes to the amount of water needed to produce 8 ounces of each, tea wins by a wide margin: 7 gallons versus 29 gallons.

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Beer drinkers of the world rejoice! Beer requires one-third less water than wine per unit. WaterFootprint.org estimates that 8 ounces of beer requires 36 gallons of water, while wine is 58 gallons for an 8 ounce glass.

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It certainly surprised me to find out that butter really has such a high water footprint: 2044 gallons per pound. That's higher than any animal-based food with the exception of beef. Cheese is less than half of butter: 896 gallons. Eggs are at the bottom of this list: 573 gallons.

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