I recently published a book titled Smart People Don’t Diet: How the Latest Science Can Help You Lose Weight Permanently (Da Capo-Lifelong books). As I talk to television, radio, and podcast hosts and a variety of other people in the process of promoting this book, I’m often asked, “Have you ever been on a diet?” I can’t lie – I have been, and I say so. I know I’m not alone though. My research suggests that most men and women have (1). We have because we’re tempted by the promises that inundate us. Lose a pound a day. Get a flat belly. Increase your metabolism. Be “thinspirational.” What’s not to like about this?

The problem? These diets don’t work! When you look at the data (and reflect on your own experiences I bet), it becomes painfully obvious. Smart people just don’t diet. Here are 6 of the best reasons not to. 

1) Dieting can make you gain weight. Here’s a little known fact: Not only do people sometimes not lose weight when they diet, but they often GAIN weight. In one study that followed dieters for two years, the average person weighed more at the end of those two years than at the beginning (2). That’s a lot of work for no reward!

2) Dieting uses valuable brain power. When people diet, they typically keep track of what they eat or spend energy “counting” calories, sugar, or fat grams. It turns out that this can be exhausting. In fact, dieting researchers have examined the mental energy (often referred to as “bandwidth”) available to dieters versus nondieters. They have consistently found that people who diet are distracted by their diets and have a more difficult time learning new information, don’t problem-solve as well, and have lower self-control (ironic, huh?) (3, 4).  In other words, dieting reduces your ability to do other, potentially more important, things.

3) Dieting leads to ironic processing. What does that mean? Well, this is probably best explained through the use of an example. What I want you to do right now is try not to think about chocolate at all. Don’t think about anything chocolate. OK, I want you to put all thoughts of chocolate out of your mind for the next 10 seconds – clear your mind and count to ten. How did that go? Well, if you had a hard time doing that little exercise, that means you are pretty normal. It’s ironic that when we try not to think about something we tend to think about it that much more. And, this is why it is so hard to not eat something we are trying not to eat!

4)  Dieting keeps you from eating “bad foods” (and some bad foods are good). What I mean by this is that evidence suggests that if we try to eliminate all “bad foods” from our diet we are likely to end up overeating them. So, it is better to just allow ourselves some regular, moderate indulgences.   In fact, in one study, when people were allowed to eat a little something sweet each day they were more likely to lose weight and keep it off than a comparison group that abstained from sweets altogether (5).

5)  Dieting leads to binging. Dieting researchers actually refer to this as the “what the hell phenomenon” (6). You see, it turns out that when we go on a diet – and inevitably pledge to avoid certain foods (e.g, carbs, sweets, fat) – we typically slip on our diets and tend to think “what the hell!” And, instead of eating just one dessert, we eat 3. Instead of eating one doughnut, we eat 4. After all, we’ll start our diet again on Monday. But, the binging in the interim is likely to contribute to weight gain, guilt, and disgust with ourselves.   It’d be better for our psyche and our waistlines to just have one dessert from the start.

6) Every time you fail on a diet you make someone else money. One thing that scientists who study weight management know without question is that the diet industry is delighted when we fail on our diets. Because, we’re likely to try again and that just makes them more money! Imagine if the first diet you tried worked – the multibillion dollar dieting industry would disappear!

So, I’ll say it one last time: Smart People Don’t Diet. And, it is never too late to become smart.


@Copyright Charlotte Markey 2015

Smart People Don’t Diet (Da Capo Lifelong Books and Nero) by Dr. Charlotte Markey is available now, here. You can follow Dr Markey on Twitter (@Char_Markey), Facebook (Dr. Charlotte Markey), Pinterest (Dr. Charlotte Markey) and on her website www.SmartPeopleDontDiet.com.



1) Markey, C. N., Markey, P. M., & Birch, L. L. (2001). Interpersonal predictors of dieting practices among married couples. Journal of Family Psychology, 15, 464-475. doi:10.1037//0893-3200.15.3.464.

2) French, S. A., Jeffery, R. W., Forster, J. L., McGovern, P. G., Kelder, S. J., & Baxter, J. (1994). Predictors of weight change over two years among a population of working adults: The Healthy Worker Project. International Journal of Obesity, 18, 145–154.

3) Mata, J., Todd, P. M., & Lippke, S. (2010). When weight management lasts: Lower perceived rule complexity increases adherence. Appetite, 54, 37–43.

4) Dax, U., Peter, C., & Polivy, J. (2002) Eat, drink and be merry for tomorrow we diet: Effects of anticipated deprivation on food intake in restrained and unrestrained eaters. Journal of Abnormal Psychology, 111, 396–401.

5) Jakubowicz, D., Froy, O., Wainstein, J., & Boaz, M. (2012). Meal timing and consumption influence ghrelin levels, appetite scores and weight loss maintenance in overweight and obese adults. Steroids, 10, 323–331.

6) Polivy, J., & Herman, C. P. (1985). Dieting and bingeing: A causal analysis. American Psychologist, 40, 193–201.