Choosing Between Carrots and Cake Is a Snap Decision, Researchers Say

Information about health and taste wage a war within the brain.

ByABC News
January 6, 2015, 4:38 PM

— -- Whether you stick to your diet or give into temptation comes down to just milliseconds, a new study suggests.

Researchers from Caltech tested this theory by asking 28 volunteers to rate the health virtues of more than 150 foods after fasting for four hours. The subjects were then shown random pairings of foods on a computer screen, one healthier than the other, then invited to choose between two.

On average, information about taste begins influencing the decision making process about 200 milliseconds sooner than health information, according to findings published in the latest issue of the journal Psychological Science.

Lead researcher Nikki Sullivan said based on how quickly subjects navigated their computer mouse to click on their selections, the scientists could tell which factor was important in making a choice -- taste or health.

"By assessing how well taste and health are related to the direction of cursor movement we were able to determine that taste was reflected in the choice process much earlier than health," Sullivan told ABC News, adding that the analysis is actually quite complicated and mathematical.

People who demonstrated high self-control by picking the healthy items such as carrots more often than not began to factor health information 323 milliseconds -- a third of a second -- sooner than those who succumbed to more sinful items, such as cake.

"Because taste comes into decision making much earlier, we believe it has an advantage," Sullivan said.

For 32 percent of the subjects, Sullivan said health never even came into play at all. For those people, making good food choices was all but impossible.

Knowing that the war in the brain waged between taste and health occurs in a timespan less than the blink of an eye might be used to help people eat better, Sullivan said.

"Something we need to test is whether or not delaying decision making will give people enough time to consider health," she said. "We'd also like to test if making health information more prominent might make it easier for that information to get through."