Are All Diets Unhealthy?

Guest blog by Cynthia M. Bulik, Ph.D., and Nadine Taylor, M.S., R.D
Author of Runaway Eating: The 8-Point Plan to Conquer Adult Food and Weight Obsessions

Want the short answer? Yes. Now, you may be thinking, "If I don't stay on some kind of diet, I'll just blow up like a balloon. I need to be on a program just to keep control of myself." But consider that any kind of dieting involves a diet mentality, which ensures failure, encourages you to ignore hunger and satiety signals, and promotes a negative relationship with food, because you have to give up "forbidden" foods and, often, eat foods you don't really like. This inevitably results in giving in, which often means bingeing and feeling terrible about yourself. So, though this idea may sound radical, we firmly believe there is no good diet.

By "diet," we mean the conscious restriction of the amounts or kind of foods you're allowed to eat for the express purpose of losing weight. A diet is something that you go on when you want to change your body, and go off once you've reached a certain goal. Though we certainly do endorse consuming a wide variety of healthful foods, paying attention to portion sizes, and thinking twice before eating a lot of foods that are high in calories but low in nutrition, we don't recommend following any kind of plan that tells you what, how much, and how often you should eat, without regard for your body's hunger and satiety signals. And we definitely don't recommend any eating plan that you go on and then go off.

Although it may sound surprising, the negative effects of dieting also hold true even if you aren't following a formal diet but still think like a dieter. If you count grams of fat, opt for high-protein foods while shunning carbs, rely on "safe" foods, beat yourself up for eating "bad" foods, consciously or unconsciously undereat (which can trigger overeating later), use diet soft drinks or coffee to quell your hunger, or decide what you can eat based on what you've already eaten today, you're dieting. 

The Physical and Psychological Effects of Dieting

Have you ever noticed that as soon as you go on a diet, all you want to do is eat? Even if you weren't particularly concerned about food prior to dieting, all of a sudden you become obsessed with it. You find yourself preoccupied with what you'll have for your next meal, whether you can have a snack, what others are eating, or even what you'll allow yourself to eat tomorrow. What's going on? 

The mind and the body are inextricably linked, and never is this more apparent than when you go on a diet. Geared to survive during feast or famine, both body and mind switch into survival mode when the food supply is radically diminished. While the body turns down the metabolism and becomes a "slow burner" in an attempt to hang on to every single calorie, the mind gears itself to one overriding purpose: getting food. The result? Suddenly, you may find yourself clipping recipes, planning menus, cooking elaborate meals or dishes for others (neither of which you'll eat yourself), or even dreaming about food at night. The message is clear: Your body wants food, and your mind does, too.

After a few days of extremely restricting your food, you'll probably become more depressed and anxious. Although this may be due to changes in neurotransmitters like serotonin, it may also occur because you are depriving yourself of things that are very pleasurable that aren't replaced by anything else -- leaving a pleasure void. You may suddenly prefer to spend more time alone -- it takes too much energy to deal with others -- and your self-esteem may start to drop. Unfortunately, the more depressed, anxious, and isolated you become, the more you'll obsess about food. 

Some people can hold out longer than others, but the result is eventually the same: a binge. You eat something you "shouldn't," which makes you feel as if you've blown it. So you let go and eat. During the binge you feel relief -- at last you can relax and do what you've wanted to do all along. But you may also feel as if you're in a trance and can't stop yourself. It's almost as if your body has developed a will of its own; it's going to feed itself whether you like it or not. As a result, you can end up eating more food in one sitting than you ever did when you weren't dieting. 

Are you crazy? Absolutely not. This is a normal, even healthy reaction to a period of semi-starvation, a reaction that made good sense during primitive times. After a period of famine, it was natural and necessary for our ancient ancestors to overeat. They needed to be able to take advantage of a feast when they had the chance, because the food supply was uncertain. To make this possible, their appetites increased after a period of famine. So the same amount of food that would have satisfied them during times of plenty left them feeling hungry after a period of semi-starvation. The same thing happens to you when you restrict food. Suddenly, you develop the urge and the capacity to binge, and you no longer feel satisfied after eating what you used to consider a normal meal. In short, restrictive dieting can trigger binges and leave you hungry even after you've eaten normal amounts of food. This is true for most Runaway Eaters, and even for those dieters who do not develop Runaway Eating problems. 

The psychological consequences of dieting were clearly illustrated in a classic study of the effects of semi-starvation done in 1950 by Ancel Keys, Ph.D., and his colleagues at the University of Minnesota. In the study, 36 healthy, young, psychologically sound males were observed over a period of 1 year. During the first 3 months, the men ate normal amounts of food; during the next 6 months, they were given half as much food; and during the last 3 months, their food allotment was gradually increased. During the semi-starvation period, the men became preoccupied with food and constantly talked about it, read cookbooks, clipped recipes, and daydreamed about eating. When a meal was served, many took an inordinately long time to eat it, trying to make it last. Over time, the men became extremely depressed, anxious, and irritable. 

Once they made it through the period of semi-starvation, the men ate nearly continuously, with some indulging in 8,000- to 10,000-calorie binges. The men reported that their hunger actually increased right after meals, and some of them continued to eat to the point of being sick without feeling satisfied. Although most of the men finally reverted to normal eating patterns within 5 months of the study's end, some continued with their new patterns of "extreme over consumption." 

We see these same patterns in dieters: the preoccupation with food; the anxiety, depression, and irritability; the tendency to go off the diet and eat more than one would have in the pre-diet days; and a propensity toward bingeing even after the diet has ended.