by Dr. David Ludwig

A fundamental problem with the calorie balance view of obesity is that it considers all calories alike, regardless of source, in some obviously awkward ways. According to this view, a pastry and a peach would affect the body in the same way, so long as we consume them in the same amounts — violating basic nutritional common sense. If this were true, why would we need dietitians at all, whose primary job is to advise which foods to eat and which to avoid? Some calories seem to be more equal than others!

To get around this predicament, nutrition experts have come to rely on the notion of the empty calorie.

Sure, having too many soft drinks may not be advisable, as this thinking goes, but not because of any negative effects of sugar itself. The only concern is that added sugar — which lacks fiber, vitamins, minerals, and other essential nutrients — will take the place of other foods that contain more of these nutrients. This argument was succinctly stated in an editorial in the prestigious American Journal of Clinical Nutrition in 2014:


“As a card-carrying dietitian in good standing, I certainly am not going to tell people to eat more sugar. But we must be clear that added sugars provide 4 [calories per gram] just like any other digestible carbohydrate and are no more likely to cause weight gain than any other calorie source. The rationale to reduce intake of added sugars . . . is to reduce calories and thereby increase nutrient density.”


But are we really to believe that a cup of Coke would be as healthy as a large apple (both with about 100 calories), if we drank it with a serving of Metamucil and a multivitamin pill?

Which isn’t to say that nutrients don’t also matter. Knowledge of nutrients helped conquer diseases of undernutrition, like pellagra (deficiency of a B vitamin), scurvy (deficiency of vitamin C), and rickets (deficiency of vitamin D). But a primary focus on nutrients has proven utterly ineffective in addressing the epidemics of chronic disease caused by overnutrition.

In fact, foods with similar nutrients can affect hormones and metabolism in profoundly different ways, determining whether we store or burn calories, build fat or muscle, feel hungry or satisfied, struggle with weight or maintain a healthy weight effortlessly, and suffer from or avoid chronic inflammation. These novel aspects of food, independent of “calorie density,” can be used to create a powerful prescription for weight loss and disease prevention.

Adapted from Always Hungry? Conquer Cravings, Retrain Your Fat Cells, and Lose Weight Permanently— Chapter 3

  • Java

    I am a registered nurse. After reading this, and other books on nutrition and allergies, I feel that today’s dietitians do not have a full grasp of the truth. Patient’s with diabetes are served orange juice, high carb meals of about 2 cups noodles and other fructose filled juices on their meal trays. Then I’m expected to keep their blood sugars controlled with insulin shots. Many express frustration at not getting their sugars under better control. I point some of them, those with true motivation to learn, to your book, but have butted heads with the dietitian staff. Just reading the lid to ice cream at this facility, takes a PhD in chemistry to understand. There are more chemicals than nutrition in there it seems. Thus I am frustrated myself that I see the general population’s health in a downward spiral.
    So I am grateful for the education your book, and others, have provided me. I am seen as progressive, (despite my age of 61, lol) by others. It has taken about 2-4 years for others see that what I have been learning is the better information. Thus other seek out what I know, and slowly I am changing other staff’s thinking as well.
    Keep up the great work and public education you have provided, and I will do my best to spread the news as well.

    • Tara L McLoughlin

      Java – I couldn’t agree with you more. Although I am not in the health care industry, I am a conscious consumer and have a son with ulcerative colitis. The lack of root cause answers in past years had me researching on my own. What did I find ultimately? My son has a gluten intolerance of some sort and does not tolerate processed carbs very well. You wouldn’t know it to look at him though because he was so thin. Understanding the physiological effects of the three macronutrients has been a god send. He is healthy, now, because he knows how to manage his condition through diet and he is no longer on the thin side.

      We need to push this message anyway we can. It takes a village, as they say and ours is growing!

      Thanks for being the type of dietitian that gets that the status quo is not working and for having the courage to push back!