Science Explains Why You Can’t Eat Just One Potato Chip – It’s The Salt

You might think fatty foods are delicious, but fat alone isn’t actually very appetizing. (The true taste of fat, according to recent research, tastes rather like frying oil that’s been heated too long.) The taste you can’t resist is due to the sugar or salt that’s often present in fatty foods.

Lately, researchers have taken a closer look at salt. Eating lots of it has been linked to obesity, even independent of calorie consumption. Some research even shows that liking salty, fatty foods is linked to overeating and overweight even more than having a taste for sweet fatty foods. Now, a new study published in the Journal of Nutrition suggests that salt is playing an even more powerful role than we thought in making us eat more.

The researchers from Deakin University in Australia recruited 48 healthy people and measured their sensitivity to the taste of fat by mixing up three drinks—identical except for the addition of a very low concentration of a fatty acid in one of them—and asking them to identify the fatty drink. Past research has found that the lucky few who are more sensitive to the taste of fat eat less of it.

Then, once a week for four weeks, everyone ate four different lunches. The lunches looked pretty much the same—elbow macaroni with tomato sauce—but the researchers manipulated the amount of salt and fat in each pasta dish. The dishes were either low-fat/low-salt, low-fat/high-salt, high-fat/low-salt, or high-fat/high-salt. They measured how much they ate and also rated their reaction to the food on scales including pleasantness, hunger and fullness.