Ground beef labeled "80% lean." Is it a low-fat food?

The label is accurate: by weight, 80/20 ground beef is 80% lean and 20% fat. But weight isn't the only way to measure it. Count calories instead, and fat is most of what you're eating.

Raw 80/20 ground beef

By weight
80% lean
what the package shows
By calories
About 71% fat
180 of its 254 calories per 3.5 oz (100 g) come from fat
Most of the "lean"
Is water
about 62% of the beef's weight, with no calories at all

The same beef, measured two ways

Each bar is the whole 3.5 oz (100 g) of beef

Two stacked bars for 100 grams of raw 80/20 ground beef. By weight: 20% fat, 17% protein, and 63% water and other. By calories: about 71% from fat and about 29% from protein. By weight: what "80% lean" measures Per 3.5 oz (100 g) of raw 80/20 ground beef Fat 20% Protein 17% Water and other 63% By calories: where the energy comes from 254 calories in the same 3.5 oz (100 g) Fat about 71% Protein about 29%

A true number can come in the unit that sounds best. "80% lean" measures weight, and most of that weight is water, which has no calories. Fat has more than twice the calories per gram of protein, so the 20% of fat by weight supplies about 71% of the calories.

The same choice shows up on plenty of labels: 2% milk is 2% fat by weight but gets about a third of its calories from fat, and a snack can be "95% fat-free" by weight while much of its energy comes from fat. When a label picks one unit, ask what the same fact looks like in another, equally true one.

What label have you read that might sound very different if it used a different unit?

How leaner blends compare
LabelFat by weightCalories per 3.5 oz (100 g), rawShare of calories from fat
80% lean / 20% fat20%254About 71%
90% lean / 10% fat10%176About 51%
93% lean / 7% fat7%152About 41%

Share of calories from fat is the fat grams × 9 calories, divided by total calories. U.S. labeling rules say that when a package states a lean percentage, it must show the fat percentage right next to it, in the same size and style of lettering.

Related exhibits

Sources: U.S. Department of Agriculture, FoodData Central, "Beef, ground, 80% lean meat / 20% fat, raw" and the 90% and 93% lean equivalents; USDA Food Safety and Inspection Service, nutrition labeling rules for ground or chopped meat (Federal Register, 2001 proposal and final rule).