College students were recruited to participate in a food perception study. The students were told to come to the lab a bit hungry and not eat at least 3 hours before.

They were led to a room which smelled of delicious freshly baked chocolate chip cookies. [Hopefully they were Dessert Angel cookies. :D]

In the room were two bowls: one with chocolates + chocolate chip cookies and the other with a bunch of radishes.

Half of these students were asked to eat 2-3 cookies and some chocolates, but no radishes. The other half were asked to eat 2-3 radishes, but no cookies.

While the students ate, the researchers left the room, intending to tempt the students who ate the radishes with the yummy cookies and chocolates.

Despite the temptation, the radish eaters showed their willpower by not sneaking any cookies.

At this point, the students were told that this taste test study was over and they could leave.

But then, by design, another group of researchers entered the room and asked if they wanted to participate in another, supposedly unrelated study. Many of the students agreed.

In this second study, the students were presented with puzzles that required them to trace a complicated geometric shape without retracing any lines or lifting their pencils. They were given multiple sheets to try over and over.

The thing is, the puzzles were designed so that they couldn’t be completed to frustrate the (poor) students to measure their persistence (aka willpower).

This is where it gets interesting

The students who ate the cookies spent 19 minutes on the task and made 34 attempts.

However, the students that ate the radishes gave up after only 8 minutes and 19 attempts!

The radish eaters, who had earlier exhibited their willpower by not sneaking any cookies or chocolates, quit in less than half the time simply because they ran out of self-control, say the researchers.

And it’s not just this one study showing this phenomenon – many others have been done that show self-control is an exhaustible resource.

If you’ve ever experienced the frustration of having been on a diet, losing weight, then gaining it all back, you, too have proved that self-control is limited.