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

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

The water footprint of meat is a higher number than many people might realize. While many Americans expect to eat a certain amount of meat, and they might think, “Well, I don’t eat that much,” they might be surprised by just how much meat (and dairy) they actually consume every day. This is an important consideration because the water footprint of meat and dairy can be much higher than that of plant foods. With a little awareness and guidance from the USDA, it’s easy to meet daily protein needs without consuming so much meat.

Americans eat a lot of meat and dairy

Here’s a quiz: How many pounds of meat does the average American eat every year? The answer might be a little shocking to some. According to the USDA, Americans, on average, are on track to eat 222 pounds of red meat and poultry in 2018, which works out to more than half a pound a day. Many probably think, “I don’t eat that much meat,” but if they kept track, they might be surprised by just how much meat (and dairy, for that matter) they actually consume.

The Water Footprint Calculator (WFC) includes questions about diet, specifically about how much meat and dairy people consume in a day. As many users have discovered, their diet can be the most significant component of their daily water footprint, especially if they consume a lot of meat and dairy. But what does that mean and why do people underestimate their consumption by so much? Just how much is one portion of meat and dairy and how much should we eat in a day?

Daily Meat Consumption in the US

As shown in Figure 1, US per capita consumption of beef, pork, lamb and poultry has hovered around 200 pounds per year but has been steadily increasing since the 1970s. This is an important consideration when it comes to water conservation because meat and dairy production has a large water footprint. The actual number varies from animal to animal and depends on the environmental conditions under which they were raised, how animals are raised – whether they were grass-fed or grain-fed – and whether or not their feed came from irrigated crops.

Take beef, for example. The water footprint of meat is contested by some in the livestock industry who disagree with how the water footprint is calculated. Nevertheless, research suggests that, on average, it takes about 1800 gallons of water to produce one pound of beef, which translates to around 450 gallons for a quarter-pound hamburger.

Interestingly, since 1970, the data indicates that the trend is for Americans to eat less beef and more pork and especially chicken. In 1970, per capita disappearance of beef was 85 pounds, whereas in 2017 that number had dropped to 57 pounds.

Figure 1. US per Capita Consumption of Beef, Pork, Lamb and Poultry 

Meat and Dairy Portion Sizes

One reason why it’s hard for people to discern portion sizes, according to the National Institutes of Health, is that portion sizes in US restaurants have doubled or even tripled over the last twenty years. Our sense of what constitutes a serving has become skewed. A McDonald’s hamburger patty (the original McDonald’s Burger® ) has 1.6 ounces of beef, while a Big Mac® has twice that amount at 3.2 ounces, a Quarter Pounder® has 4 ounces, and now there’s even a Double Quarter Pounder® that features a full 8 ounces (a half a pound) of beef. People may be getting better economic value when they get bigger portions for a few pennies more, but there is a high environmental cost associated with that value.

It’s hard to judge what a USDA-recommended portion of beef, chicken or cheese looks like. Visual cues are helpful; for example:

  • A portion of meat varies from the size of a deck of cards to a checkbook (3 ounces)
  • A portion of cheese is the size of three dice (1 ½ ounces)
  • A portion of yogurt is the size of a baseball (1 cup)

Meat and Dairy Serving Recommendations

A much more complicated issue is determining how much meat and dairy people should consume on a daily basis. The USDA’s MyPlate nutrition guidelines do not make blanket recommendations about meat and dairy. Their guidance states instead that, “The amount of food from the Protein [and Dairy] Foods Group you need to eat depends on age, sex and level of physical activity.” Still, MyPlate generally recommends 5 to 6 ounces of “protein equivalents” per day for adults which includes beans, nuts and eggs in addition to meat. It also recommends 3 cups of “dairy equivalents” per day, which include cheese, yogurt and calcium-fortified soymilk.

Clearly, people in the US are exceeding this guidance each day. Remember, there is protein in tofu, beans, quinoa, leafy green vegetables and many other foods, so these foods can help reduce the amount of meat required to meet daily protein needs. The MyPlate guidelines are a useful starting point, of course, but ultimately people have to listen to their own bodies and do what feels best for them. And the water footprint of tofu is significantly less than the water footprint of meat and dairy.

By being more conscious of how much meat and dairy they actually eat and trying some of the non-meat protein sources mentioned above, people can make significant reductions in their daily water footprint. In this case, being “below average” is a good thing for the health of the planet. If people are making a conscious effort to reduce their water footprint, eating a little less meat is a great way to do it.


The food people eat has an impact on their health, the environment and on the welfare of animals and workers. FoodPrint has many tools and resources to help people eat sustainably.