The 900 Gallon Diet: Meat, Portion Size and Water Footprints

Here's a quiz for you: How many ounces of meat does the average American eat every day? The answer: Eight oz (half a pound). You're probably thinking, "I would never eat that much meat." If you kept track, you might be surprised by just how much meat (and dairy) you actually consume.

My colleagues and I were talking about this because we have a question on our Water Footprint Calculator (WFC) about how much meat and dairy people eat. This is an important question because the water use associated with meat and dairy production can translate into a larger water footprint (aka virtual water use) than a person's direct water use. To be fair, the water use varies from animal to animal and depends on how the animals were raised (grass-fed vs. grain fed) and whether or not the grain they were fed was from an irrigated plant.

This is a hotly contested number in the water footprinting arena, but most research on the subject suggests that, on average, it takes 1800 gallons of water to produce one pound of beef (which translates to 900 gallons of water consumed per day based on average American meat consumption). We frequently get feedback on the WFC from people who say that they don't eat anywhere near that much and our calculator must be inaccurate. While there may be those that make a conscious effort to reduce how much they eat, what seems more likely is that people don't realize how much meat and dairy they are actually consuming and they underestimate their water footprint as a result.

How is it that people underestimate their consumption and what does a serving of meat even mean anymore? Portion sizes have increased significantly over the past sixty years with the domination of fast food. Our sense of what constitutes one portion has become skewed. A McDonald's hamburger patty (the original McDonald's Burger© ) has 1.6 oz of meat, a Big Mac© has twice that at 3.2 oz and a Quarter Pounder© has 4 oz of meat. People may think they're getting a better value when they get bigger portions for a few pennies more but there is a high environmental cost associated with that "value."

Just how much is one portion of meat and dairy and what does it look like? I asked our resident nutrition expert, Dawn Brighid, to explain portion sizes in an easy to remember manner.

From Dawn:

It's hard to judge what an ounce of beef, chicken or cheese looks like, and it turns out that it isn't very big. Visual cues are very helpful.

  • A portion of meat is the size of a deck of cards (2 to 3 oz).
  • A portion of cheese is the size of two 9 volt batteries (1 ½ oz).
  • A portion of milk is the size of a small milk carton (8 oz).

A more complicated issue is determining how many daily servings of meat and dairy people actually need. The USDA's daily recommendation is 2 to 3 servings of meat and 2 to 3 servings of dairy. This means a minimum of 4 to 6 oz of meat and a minimum of 2 cups of milk. And most Americans eat more meat and dairy than that. If they were to measure their intake each day, most would probably find that they've gone way overboard.

It's easy to see that if you follow the USDA recommendations, your meat and dairy servings quickly add up to the eight oz (or more) mentioned above (and your water footprint quickly increases). Did you put cream in your coffee? Or maybe you had some yogurt or a little sour cream on your food. You may also have had eggs or bacon for breakfast. All these items have a large water footprint attached to them.

Dawn continues:

I suggest you use the USDA recommendations as a guideline, and then listen to your body and do what feels best for you. Remember that the USDA also includes beans, nuts, eggs, fish and poultry in the "meat" category and cheese and yogurt in the "milk" category. You can also get protein from tofu, quinoa and dark, leafy, green vegetables. Be sure to include all of these food items when you are determining your daily intake. A wonderful visual guide is available from the USDA in The Nutrition Newsletter for Parents of Young Children.

I'm not advocating that people stop eating meat, in fact I enjoy cooking and eating it and would probably eat more bacon if it weren't so hard on the animals, the planet or my health. Instead I advocate for making informed choices and understanding that what you eat has environmental consequences.

Our friends at Meatless Monday advocate eating 15 percent less meat by going meatless just one day per week. Doing this can have a significant impact on your daily water use (not to mention things like carbon emissions).

Be more conscious of how much meat you're actually eating and try some of those other protein sources Dawn mentioned above. Be adventurous! Be "below average" and feel good about it. If you're making a conscious effort to conserve water, eating a little less meat is a great way to do it.