All Calories are Equal, But Some are More Equal than Others

This is a guest blog post by Janet Helm, MS, RD. It originally appeared in Cooking Light.

Last summer, Mark Haub, Ph.D, an associate professor of nutrition at Kansas State University, made headlines when he lost 27 pounds after two months of living on Twinkies, Ho-Hos, Little Debbies, and other convenience-store snack cakes.

Haub’s experiment reinforced the calories-in/calories-out equation: If you drastically cut back—as Haub did, from 2,600 to 1,800 calories per day—you will lose weight, no matter how nutrient-deprived your diet may otherwise be. Anyone who knows what calories are—units of energy—knows this to be so.

But lost in the brouhaha surrounding the so-called Twinkie Diet was a more interesting trend: a revision of the idea that all calories are equal. New studies hint that the body may burn calories from whole foods better than it does calories from processed foods like Twinkies. Essentially, it appears the body can “burn” a bit hotter on whole foods and use healthier fuel at the same time. That’s great news for people who want to follow the new Dietary Guidelines, because it addresses two big problems with the American diet: calorie overload and nutrient inadequacy.

While Dr. Haub was carefully counting his Twinkie calories, a group of scientists from Pomona College in California were preparing to publish a small study with interesting implications for anyone who wants to maintain a healthy weight and eat good food.

The researchers fed people two meals with the exact same number of calories; the only difference was how much the food was processed. Group A was treated to sandwiches made with real cheese on whole-grain bread; Group B made do with processed cheese on fiber-stripped white bread. The results, published in Food & Nutrition Research, found that the processed meal decreased the rate of diet-induced thermogenesis—the number of calories you burn when eating and digesting—by nearly 50% compared to the meal made with whole foods.

The calories burned from a single sandwich may be small, but this rise in metabolism caused by whole foods (known as the thermic effect) might account for about 10% of a typical person’s daily calorie expenditure. Although more research is needed, early indicators show that whole foods may offer a real metabolic advantage for calorie counters. Whole foods aren’t just better for you because they’re more nutritious, but they also may be, essentially, lower-calorie.

Weight Watchers, recognizing the differences in how our bodies react to calories—and nudging dieters to eat more whole foods—revamped its points system late last year to make fresh fruits and most vegetables “free.” Eat all you want, the WW plan says. In general, foods higher in fiber and protein were assigned fewer points, and processed foods were given more.

All this comes at a time when calories are back in the nutrition spotlight. The fat-phobia and obsessive carb-counting eras are waning. Governments are talking about “soda taxes” to combat the health costs of consuming too many “empty” calories. Calorie labeling is showing up—voluntarily and by law—on more restaurant menus, and calorie counts are more prominent on some food labels.

This calorie consciousness is a good and a bad thing. Most Americans do need to cut back on calories. Balancing energy in and energy out (which brings in the whole question of exercise) is critical to solving the obesity crisis. But calorie counting per se is tedious and not the real answer, unless you want to go on a Twinkie diet. The better approach is the whole foods approach, because Americans also need to increase intake of a long list of nutrients, including fiber, potassium, calcium, and vitamin D, which are associated with whole foods. Eating more fruits, vegetables, and whole grains delivers those nutrients in a form that may also hold a calorie-burning advantage.

Janet Helm is a writer, registered dietitian and mom of twins.  She is a frequent contributor to the Chicago Tribune and has been a media spokesperson for the American Dietetic Association. Janet blogs at Nutrition Unplugged and is the founder of the Nutrition Blog Network.

Get Fooducated: iPhone App RSS Subscription or Email Subscription

Follow us on twitter: on facebook:

  • maebyn

    Do you have a reference for the study from Pomona College?

  • JS

    Great Article, I absolutely agree that the key to weight loss is to simply create a deficit of energy which is more easily achieved by a diet rich in fruits and vegetables as they are inherently low calorie foods.

  • Nurture Nutrition

    I’d love to see if he has put the weight back on. Most people can restrict their diets for a few months but then the hypothalamus does an incredible job of maintaining homeostasis and providing the hunger/satiety signals and slowing down the metabolism to return the body to the higher weight. There has yet to be a diet plan that actually has decent LONG TERM research results for people.
    Calories in vs. calories out simply does not take into consideration our body’s true biological regulation capacity. We can fight it for awhile but eventually it will win out. Luckily, focusing on changing HEALTH behaviors, not WEIGHT, will improve health outcomes.
    Check out the “Health At Every Size” book by Dr. Linda Bacon.

    • Dr. Haub

      I am 2 lbs (176) heavier now than when I finished week 10 (174, 11/05/2010). That includes a post diet BBQ, Thanksgiving, Chrismas, New Years, Superbowl, and anniversary celebrations in between. According to clinical markers, my HEALTH, as you alluded, did improve — mental and physical.

      Bear in mind the HAES message is/was a key aspect of this class project and my lifestyle. I believe health outcomes (mental, physical, spiritual, etc.), outside of weight, should be the target. I think individuals need to meet the nutrition needs, yet not over or under consume too much on a regular basis — at least that is a general/initial rule of thumb. This covers those with metabolic syndrome issues as well as those with eating disorders. If someone changes their lifestyle, weight may or may not change and I do not feel it wt change is that important, as long as their quality of life improves and their internal indicators of health ‘improve’. I am open to debate when BMI > 50, but still feel that personal preferences and quality of life should dictate decisions maybe with some education or advice to assist.

      Great questions and comments. I am still working on what the next project will be. I will likely let the students decide this time (I have to agree, of course).

      Cheers — Mark

  • Mr. Bill

    As my favorite engineering professor would say: “In equals out… unless it doesn’t” (there is 5yr of college right there). If they are not equal, something is wrong and things could get explosive.

  • Rachel Assuncao, Health Coach

    Great article. Healthy, whole foods must be the focus of our diets – for weight loss and disease prevention. It’s nice to see a study that supports this to balance out the media craze that happened over the Twinkie Diet.

  • Dwmatty

    This makes a lot of sense. Although calories in-calories out equates to weight loss or gain, the source of those calories is even more important for overall health.

  • WW_Renee

    I mostly love the post. I believe strongly in eating whole foods, and love to see more people getting the word out.

    And I appreciate the plug for Weight Watchers, as it helped me lose 45 pounds in 2003 and I maintained that weight lost for 5 years until I got pregnant. I also lost my baby weight on Weight Watchers last year, some of it (towards the end) on the new PointsPlus plan.

    I must point out that you have one serious misinterpretation of the Weight Watchers plan. In regards to the zero PointsPlus fruit you state “Eat all you want, the WW plan says.” NEVER does WW say that. Not even about fruits and vegetables. It is all about learning to eat until you are satisfied. Weight Watchers isn’t just about PointsPlus in, PointsPlus out. A big part of the plan is (re)learning how to eat in a healthy way. Sure it is better (from a caloric standpoint) to mindlessly eat grapes than it is to mindlessly eat M&Ms, but neither of those short-term actions create the long-term success of changing how we think about food. “Eating all you want” is never a healthy habit, and WW is all about helping members learn healthy habits. PLEASE don’t ever assert that WW says “eat all you want” about anything. It just isn’t true.

  • QuipsTravails

    It also should be noted that while Mr. Haub’ diet was calorie-controlled, it was not exclusively junk foods: he drank a protein shake daily, took a multivitamin and ate a can of veggies daily. Done that way, it’s hardly a representation of the diet eaten by most junk food junkies.

    • Dr. Haub

      Absolutely, and great job looking beyond ‘what’ was eaten and viewing the foods collectively to ‘how’ and ‘why’ the foods were selected!…thus, it’s not the food/ingredients (sugar, HFCS, trans-fats, SoFAS, refined grains, any ingredient demonized for ‘going straight to my hips’) — it’s how/why they’re eaten. We as a society have become too focused/worried about “what” we eat and have lost sight of why we eat and how (much) to eat. The new bacon/maple sundae at Denny’s is an example.

      Most of us are no longer active enough and food/energy is too convenient to not be aware of eating (excluding those like Michael Phelps, or me running 90 miles/wk 20 yrs ago). Basically, ‘all’ diets require awareness – paleo, Atkins, vegan, Ornish, WW, and even my lower-carb-nutrient-adequate-snack-cake lifestyle. The foods eaten in those lifestyles can be used as tools to affect health.

      A point of the project was to illustrate that regardless of the path/diet/food chosen, established markers of health can improve; and, yes, it is possible the established markers are not valid in all cases (and that was discussed in class :-) . It is my professional belief that we can eat better, and optimal may not be realistic due to costs/availability of the food and the capacity to buy and/or prepare it daily.

      Should we really judge people and attempt to control “what” people eat? Does it matter to us what others eat if they’re healthy/healthier?

      • Fooducate

        Thanks Dr. Haub for chiming in. Nobody should control what other people eat. But that also includes the corporations that spend billions of advertising dollars trying to do just that…

  • Carol

    It makes sense that less refined carbohydrate foods would be more “work” for the body to process, and therefore burn more calories doing so.

  • Sam Montana

    This is very interesting and so is the Pomona study. It is well known that processed foods do not have the nutritional value of whole foods, no matter how much they fortify and enrich them. I have wondered if all the chemical additives have not caused the obesity rates to rise. There have been studies how MSG and other additives can cause our body to think it is still hungry, not turn off a certain gene that regulates when we feel hungry or full. There are more chemicals and fillers in processed foods than there is actual food anymore.