Does Eating Whole Foods Burn More Calories?
A calorie is just a calorie. We get it. But what if it isn't?
What if it was more difficult to digest whole foods? What if you actually expend fewer calories digesting processed foods? This would make a whole foods-centric diet the obvious and best choice for dieters.
That is the question. But I know what you're thinking. We all know that protein takes more energy to digest, but does it really make that much of a difference?
Related - Is a Calorie Just a Calorie?
Before I analyze the current information we have on the thermic effect of eating whole foods versus processed foods, let's take a look at the real world impact that the thermal effect of digestion (thermal effect of food) has when you switch to a higher protein diet.
Note: TEF is the abbreviation for the thermal effect of food. This measuring stick basically tells us how much energy it takes to digest a micronutrient or specific whole or processed food.
Macronutrients - The Thermal Effect
According to the Journal of Nutrition, here are some estimates for the thermal effect of digesting carbs, protein, and fats: 
- Carbs - 5 to 15% of the overall total carb calories are used or burned away during digestion.
- Fats - 5 to 15% of the overall total carb calories are used or burned away during digestion. (OR 0 to 3%, depending on sources.)
- Protein - 20 to 35% of the overall total carb calories are used or burned away during digestion.
Some sources believe that the percentage listed for fats is on the high side and that they are very easy to digest. YouTube bodybuilder James Tiny Vest is one of these voices.  He states:
"Fats. They claim 5 to 15%. I disagree with that. I'm going to say that's a little high. I think that fats require so little (energy to digest). And if you go and do your own research you'll see where I am coming to these conclusions from."
It should be noted that there are three ways the body burns, or expends energy on a daily basis.
- Thermic effect of food, or calories burned digesting the food we eat.
- Your BMR, or basal metabolic rate. This is the number of calories it takes to sustain your body in a completely restful state.
- Activity-induced thermogenesis, which is the calories burned from movement or activity.
For someone trying to lose weight, there are only two ways to increase energy expenditure: move more, or eat foods that require more energy to digest. Before you get your hopes up that switching to a higher-protein diet will cause fat to melt off, let's analyze just how important the thermal effect of food really is.
DIT is dietary-induced thermogenesis. It is the amount of energy we burn digesting and processing our food. You will soon see why DIT isn't very important when considering what types of macronutrients we should eat.
Example - 2500 Calorie Daily Intake
For our example, we will consider an individual with a 2,500 daily calorie intake. They will be boosting protein intake from 150 to 220 grams per day, or a daily increase of 70 grams. This is a pretty substantial increase.
Let's see how many calories it burns.
Here is the macronutrient breakdown before the increase in protein:
- Protein - 150 grams, or 600 calories.
- Carbs - 295 grams, or 1180 calories.
- Fats - 90 grams, or 720 calories.
Now, after the change:
- Protein - 220 grams, or 880 calories.
- Carbs - 225 grams, or 900 calories.
- Fats - 90 grams, or 720 calories.
Looking at averages, it took 118 calories to digest carbohydrates and 165 calories to burn the protein. We'll ignore calories to process fats since the number remains equal (and potentially minimal) in both cases.
This is a total of 283 calories burned from carbs and protein.
Now let's increase the protein intake. Looking at averages, it took 90 calories to digest carbohydrates and nearly 242 calories to burn the protein.
This is a total of 332 calories burned from carbs and protein.
Feeling sad? Likely so. Dramatically increasing your daily protein intake only resulted in an increase of 49 calories burned. This equates to an extra 17,885 calories burned per year or a loss of 5.11 more pounds of fat.
Is five pounds a year really that bad? No, but considering you can easily lose 8-12 pounds a month by reducing calories, it's a very trivial difference.
Now, if you were eating very little protein, say 80 grams per day, and bumped that up to 220... That would be almost an extra pound per month. Almost.
So let's get back on track and take a look at the point of this article. Will eating whole foods burn more calories than eating processed foods? If so, is the difference negligible?
Whole Foods and Junk Foods - The Thermal Effect
Let's open the discussion by analyzing cheese sandwiches. Yes, you read that correctly.
A 2010 study had the goal of determining whether processing food changes its TEF, or how efficiently it was digested.
In this study, 17 normal-weight individuals ate both a whole foods meal and a processed foods meal. Half of the participants were women. A pretty reasonable research pool, all things considered.
Now, by "meal" understand we are talking about cheese sandwiches here. Not exactly a normal, well-rounded meal, but for the purpose of this study it worked well.
The "whole foods" cheese sandwich contained real cheddar cheese and multi-grain bread, while the "junk" sandwich was comprised of white bread and some random and disgusting fake, orange cheese product.
Now granted, both of these sandwiches contained processed ingredients. It's a bit of a misnomer to call the whole foods sandwich whole foods, but we certainly can respect the difference in the quality of ingredients.
Simply put, the white flour bread slab and the orange oil shingle are crap foods, barely a step above eating corn chips for lunch. Or maybe not.
Without getting into all the fake-cheese details, participants that consumed the better choice burned 46.8% more energy during digestions. There was no difference in satiety, though.
Now, it must be noted that the "whole foods" cheese sandwich had an additional 10 grams of protein (per 800 calorie meal). This accounted for a small difference in energy required to digest the meals.
Overall, a 46.8% difference sounds impressive. Let's break that down further to see what it really means. Here are the real-world calorie amounts required to digest and process each sandwich:
- Whole foods cheese sandwich - 137.7 calories, or 17.08% of the total energy contained in the meal.
- Junk food cheese sandwich - 74.1 calories, or 9.26% of the total energy contained in the meal.
This is actually a stunning - and substantial - difference. Think about it...
Let's go back to our 2,500 calories per day example. If our (unlucky) subject ate 2,500 calories of cheese sandwiches per day, he would burn off the following amount of calories to digest the food:
- Whole foods cheese sandwich - 430.3 calories used to digest.
- Junk food cheese sandwich - 231.6 calories used to digest.
So, about 200 calories.
Whole food sandwich munchers would be eating about 31 more grams of protein per day, which would only be a small percentage of this overall difference.
200 calories a day is fairly noteworthy. That equals to nearly 21 pounds of additional weight per year.
What could cause such a dramatic difference in ease of digestion? I would speculate:
- Lack of fiber
- Lack of protein
- Lack of micronutrient density
- Perhaps the crap oils, white sugar, and flour are relatively easier to digest
Bloatlord Bob Versus Clean Joe
Want to take this to the extreme? Let's compare clean Joe, who eats only 2,500 calories of whole foods per day, to bloatlord Bob, who gobbles down 5,000 of processed food per day.
- Clean Joe - 2,500 daily intake, 430.3 calories to digest his food. Net intake of 2,069.7 calories.
- Bloatlord Bob - 5,000 daily intake, 463.2 calories to digest his food. Net intake of 4,536.8 calories.
This is a potential weight difference of 257 pounds in a year. Read. That. Back. Slowly.
Obviously, one study doesn't paint a complete picture. Let's explore the concept a bit more.
You "Dirty Food-Eating" Rat
In a study on rats, researchers found that when the furry rodents consumed peanuts instead of peanut butter, they lost more weight.  It's an obvious conclusion that the difference in weight was likely due to a difference in the energy required to digest each variant.
Interestingly enough, the same thing happens to beef when it is manipulated into ground or processed beef. It becomes much easier to digest. 
More research is certainly needed. With that said, when we rationally process what we already know, it makes a lot of sense why processed foods require fewer calories to digest.
The obesity puzzle is rather simple when studied under this lens. Growing portions sizes (and caloric intake) combined with a greater reliance on processed foods creates a perfect storm for an obesity epidemic.
Those that struggle to lose weight need to not only focus on calorie intake but also the quality of food. There is no downside to this approach.
It is the only reasonable - and sane - direction forward.
1) Glickman, N; Mitchell, HH (Jul 10, 1948). "The total specific dynamic action of high-protein and high-carbohydrate diets on human subjects." (PDF). The Journal of Nutrition. 36 (1): 41?57.
2) "A Calorie Is NOT A Calorie." YouTube, www.youtube.com/watch?v=mkiay95dATQ.
3) Barr SB and Wright JC.Postprandial energy expenditure in whole-food and processed-food meals: implications for daily energy expenditure. Food Nutr Res. 2010 Jul 2;54. doi: 10.3402/fnr.v54i0.5144.
4) "Cooking Increases Net Energy Gain from a Lipid-rich Food." PubMed Central (PMC), www.ncbi.nlm.nih.gov/pmc/articles/PMC4272645/.
5) Boback SM , et al. "Cooking and Grinding Reduces the Cost of Meat Digestion. - PubMed - NCBI." National Center for Biotechnology Information, www.ncbi.nlm.nih.gov/pubmed/17827047.