"I Can’t, I Am on a Diet"

Release time: 2021-07-01 16:22

"I Can’t, I Am on a Diet"

Do you eat when it is time to eat or when you are hungry? Does dieting have to be a way of life or is there a way to maintain a healthy weight while still enjoying good food?


  • Changing the way you schedule your activities can influence your eating habits.

  • What does the clock have to do with gaining weight?

  • For some, eating has nothing to do with being hungry.

“I can’t, I am on a diet,” I said, as I watched the luscious, rich chocolate cake being sliced and passed around the table. It was my best friend’s birthday and we were celebrating. My friend

looked at me and asked: “is there ever a time you are not on a diet?” My friend was right, this has been my reaction ever since I was a teenager, and that was when I realized that, for me, dieting was a way of life.

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I always counted my daily calorie intake and was very careful of what I ate. Looking at my friend, though, who just had a spoonful of what looked like a very delicious cake, I was puzzled, since as long as I can remember, she always ate what she wanted and yet looked quite amazing.

Years later, when I became a behavioral science researcher, I reexamined this phenomenon: why some people seem as if they can eat whatever they want and not gain weight while others, like me, feel it is an ongoing struggle?

External versus internal cues

In my post Why keeping time might prevent you from being happy, I introduced the concept of scheduling style, discussing how people naturally tend to be either clock timers or event timers. There I explain how clock timers rely on an external cue, the clock, to dictate their activities, while event timers rely on an internal cue, their own sense of readiness to dictate their activities. One might argue, well what does that have to do with eating and keeping a healthy weight? Turns out, a lot.

Let’s start with the external versus internal cues. Relying on an external cue to plan your day, for one, will determine when your next meal will be eaten. Breakfast at 8am, lunch at 12:30 and dinner at 7:30. This will happen regardless of how hungry you are. Some days you might be starving while others you might wonder if you could have waited a bit longer or skipped the meal altogether.

In order to indeed stick to the schedule, hunger gradually stops being the cue for eating and time becomes the main determinant. This already throws the body off balance, as hunger is the body’s way to tell us that it is time to refuel, or alternatively, maybe no additional fuel is necessary and a meal can be skipped. Indeed when surveyed about their eating habits, clock timers admitted they “eat when it is time to eat” and that “even if I am hungry, I wait for the next meal before eating.” as compared to event timers, who scored very low on these two items.

Portion control

A downstream consequence of not relying on hunger to start a meal is losing it as a cue to finish a meal. How can one tell when the meal is over if hunger can no longer be relied upon?

Turns out that clock timers use another external cue to determine when the meal is over—the emptiness of their plate. In a study that was run on college students, each student was presented with a plate of three squares of chocolate brownies. The student was then told to eat one square, and rate its flavor. The researcher was then called out of the room “unexpectedly”, but before leaving declared the study is over and the student free to eat the rest of the brownies if they wanted.

The percentage of students who ate the additional brownies was highly correlated with whether they were clock timers or event timers: The percentage of clock timers who finished the other two brownies was great than event timers. When asked what determined their decision, event timers said: “I usually stop eating when I start feeling full.” Clock-timers said they ate the brownies because they were there and tasted good.

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Have your cake and eat it too

I assume that by now you can guess that the friend who had a spoonful of her cake is an event timer, while I, who was constantly dieting, am a clock timer. As an event timer, she could eat whatever she wanted, as naturally, she ate only the portions that suited her body—lke eating only one spoonful of her birthday cake instead of the whole slice.

As a clock timer, one has to find alternative external cues to hunger—such as counting calories and avoiding high-calorie foods altogether. That method works, but prevents one from enjoying the better things in life.

What did I decide to do? I decided to go back to my natural roots and reprogram my body to eat only when it is hungry. That can mean smaller meals more frequently or days where there is only one very large meal. It does require more effort on my part, as most of my day is planned by the clock. But I treat meals as an “outside activity” that is added spontaneously as the day evolves. Gradually I trained my body to listen to its natural tendency, and finally I can stop saying: "I can’t, I am on a diet."


Tamar Avnet, Ph.D., is Chair of Marketing and Professor of Business in Marketing at Yeshiva University, New York City, and an active researcher in marketing, management, and psychology.

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