People who say they don't add salt to food are probably telling the truth.
So concludes a team of researchers in Minnesota, who secretly watched 211 people in two University of Minnesota cafeterias and then interviewed them about their salt habits.
Of those who said they "never" salt their food before tasting it, only 6 percent had been seen doing so. Of those who said they never salt food after tasting it, only 3 percent were seen doing so.
Between 10 and 20 percent of Americans are at risk of developing high blood pressure and should avoid salt, researchers Maurice B. Mittelmark of the University of Minnesota and Barbara Sternberg of Weight Watchers International write in the American Journal of Public health.
Of the salt eaten in the United States, at least 30 percent is discretionary -- added either during cooking or at the table.
The study suggests that there are two distinct kinds of discretionary salt use: by habit, which means adding it before tasting the food, and by preference, adding it after tasting.
The researchers say it may be easier to get people to cut down on using salt by habit -- before tasting -- than on using salt by preference -- after tasting.
Older and overweight people were the most likely to salt food before tasting it, which suggests that their "eating pattern . . . is driven more by habit than by preference."
The researchers found that 34 percent of the people salted their food: 19 percent before tasting it, 17 percent afterwards. Two percent added salt both before and after tasting the food.
In the study, using salt was defined as "picking up the salt shaker, turning it upside down in a salting motion over the food, and placing it back on the table."