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episode #253

Study! Is a Calorie a Calorie?!

May 22, 2023 in Podcast


This week I reviewed an interesting study comparing the postprandial thermogenic responses to whole food sandwiches made of multi-grain bread and real cheddar cheese compared to processed food sandwiches that were made with white bread and processed cheese.

The study compared what happened when 17 volunteers ate a whole food meal versus a processed food meal. Volunteers were all of normal weight, and about 25 years old. Conclusion: Eating whole food took 46.8% more energy to digest on average than processed food!

This proves that eating costs calories also known as TEF (thermic effect of food). It takes calories to chew, swallow, churn the stomach, make the acid in the stomach, make the enzymes, to make the rhythmic muscular contractions known as peristalsis that drive the food through, and so forth. From this study, it seems that not only does macronutrient content change TEF, but processing changes TEF.

Bottom Line: Processed food takes less energy to digest and absorb compared to whole foods, so 100 calories of processed food ends up being more net calories than 100 calories of whole foods. If you’re trying to lose weight, this makes the case to eat whole foods and avoid foods in boxes/cans as much as possible!

Episode Links:

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.

Junk Food Diet:


Brian (1s):

Hello and welcome to the Get Lean and Eat Clean podcast. My name is Brian Grn. I'm a certified health coach, trainer and author, and this podcast is for middle-aged men and women looking to optimize their health and get their bodies back to what it once was 10 to 15 years ago. I will give you simple, actionable items to get long-term sustainable results. Thanks for listening and enjoy the show. All right, welcome to the Getline e Klean podcast. My name is Brian Grn. I hope you had a great weekend. Happy Tuesday if you're listening to this on Tuesday, and hopefully you'll listen to my interview with Sally Norton.

Brian (43s):

She's an Ivy League nutritionist, author of the book, toxic Superfoods, how Oxalate Overload Is Making You Sick and How to Get Better. So we discussed all about oxalates. If you've never heard about what an oxalate is, I definitely would tune in. And we had, we discussed how it affected her health. You know, the problem with so-called super foods like such as almonds and spinach and you know, ways you can detox from oxalates, advantages of calcium and lemon juice in your diet and much, much more. So definitely worth a listen. My interview with Sally Norton and today on today's micro podcast I wanna discuss a study, an oldie book Goodie.

Brian (1m 26s):

I know you, you guys enjoy when we bring up some studies that are applicable to your life. And I thought this was, so let me just pull up, if you're watching on YouTube, I'll share my screen real quick just so you can see the study. Definitely I'll leave a, leave a link in the show notes so you can, if you want to read the entire study, go ahead. I'm gonna just give you the highlights, but the title is Host Perennial Energy Expenditure in Whole Food and Processed Food Meals, implications of Daily Energy Expenditure. And this was done in 2010. So as we go through this, you'll see they compared Whole Foods, well I should say a whole food versus a processed cheese sandwich.

Brian (2m 11s):

So a multi-grain grain bread and a ch and like a quality cheese versus a processed bread and a processed cheese product. So pretty interesting just comparing how the, that can affect your daily energy expenditure. And I'm, I'm gonna jump on into this study in a minute. Before I get into that, I just wanna touch on the fact that this sort of counteracts a little bit, the argument of a calories just a calorie. Cuz I think to the end of the day, to the, to the end of what our, our lifetime, there's gonna be arguments whether calories and calories out is the most important thing.

Brian (2m 52s):

And I think it plays a role. I don't think it's the only thing. And I, and so like, you know, there's an individual Dr. Mark hub, who was a nutrition professor who lost like 27 pounds on a junk food diet. I'll leave a sh I'll leave a link in the show notes if you wanna check out. The study wasn't really a study, it was more, more an experiment and it was the, he was literally promoting eating candy bars and Twinkies to lose weight. Now, did he lose weight? Yes. And he ate, he lost weight because he ate fewer calories. So yes, calories do matter, but you'll see from this study that maybe it's, it's more calories are more than just what, you know, a hundred calories from a candy bar and a hundred calories from, you know, let's just say broccoli do play a different role as you digest them.

Brian (3m 46s):

And so yes, you can lose weight by eating fewer calories. Is that sustainable long term? You know, for most people know, and a lot of times what happens is they end up just gaining the weight back. But calories do matter. Calories do matter, I will say, but, but different calories mean different things. And in the study it sort of explains the fact that, you know, this thermic effect, which I've talked about with protein plays a role and digesting food costs energy, right? So like if, for example, celery has what's called like negative calories, it takes more energy to break down and absorb the celery than the celery actually contains.

Brian (4m 29s):

So eating cost calories, right? It costs, you get, there's calories to chew it, to swallow, to churn through the stomach, to, to make the acid in the stomach, to make the enzymes, so on and so forth, right? So this is sort of like I've talked about before with protein, this thermic effect or also called dietary induced thermogenesis. So on average, a person uses about 10% of their daily energy expenditure digesting and absorbing food. But this percentage changes depending on the type of food you eat. So protein takes the most energy to digest, right?

Brian (5m 10s):

And I've talked about that recently on a podcast, 20 to 30% of your calories in protein eaten go to digesting it. Okay, I'll say that again. 20 to 30% of the total calories in protein goes to digesting it. Next is carbs, it's about five to 10%, and then fats are about zero to 3%. So if you eat a hundred calories from protein, your body's gonna use 20 to 30 of those calories to digest and absorb the protein. So you'd be left with a net 70, 70 to 80 calories as opposed to if you have carbohydrates, you'd have a net 90 to 95 calories and fat would give you about 97 to a hundred calories.

Brian (5m 54s):

So the argument that a calories a calorie doesn't hold up up so much with this argument showing this thermic effect and how it takes a certain amount of energy to digest these foods. And depending on the macronutrient, you know, de depends on how much it costs you it to actually digest it. This study happened to sort of show that 17 volunteers who ate whole food versus of processed meal food that, you know, th this comes into play when it, when the thermic effects of food comes into play, not only on macronutrients, but also on the processing of the food.

Brian (6m 35s):

So all of these volunteers were normal weight and they were about 25 years old. So the meals, as I mentioned before, these were cheese sandwiches, okay? And in the study, the metabolic impact of whole food sandwiches made of multi-grain bread and real cheddar trees were compared to processed food sandwiches, as I mentioned, that were made of white bread and processed cheese products. So, you know, one was like a whole food, the other was processed food, but they were both, you know, processed to some degree. Just one was more processed, let's just say that. So, to, to just give you what was in those, the whole food sandwiches for two of 'em, it was 800 calories and both, both were 800 calories.

Brian (7m 26s):

So same amount of calories, the whole food meal had a little bit more fat. The processed food meal had a little more carbs, and the whole food meal had 12 grams. Actually, I'm gonna share the screen real quick. You could see it for your own eyes if you're watching on YouTube. And there you go. So this is showing the differences in the two sandwiches. The biggest ones, and I bolded right here, are fiber, more fiber in the whole food sandwich compared to the processed food. And then the other one was protein. So there you go, you got a bigger thermic effect from the whole food meal.

Brian (8m 10s):

So I'll read you the ingredient list real quick of the, the whole, the cheeses, right? So like you talk about whole foods. So the, the less processed cheese was just pasteurized milk, cheese culture, salt enzymes, and anto antos of vegetable color. So let's say like five ingredients, the cheese in the processed one was milk, whey milk, fat, milk, protein concentrate, salt, calcium, phosphate, sodium citrate, whey protein concentrate, sodium phosphate, sorbic acid, anto enzymes, vitamin D three, cheese culture.

Brian (8m 52s):

So typically more processed foods have more ingredients. So I always say if you can eat foods that have less than six ingredients, give or take, you're, you're, you're ahead of the game. That's the way to go. And from the study eating the whole food, that whole cheese sandwich, the one that was less processed took 46.8% more energy to digest on average than the processed food. That's a big statement, right? This almost took, almost took 50% more energy to digest the whole food versus the processed food. Now, like I said before, what explains this difference between the two?

Brian (9m 33s):

Well, protein and fiber I would say play a part, right? Like I said, the whole food sandwich had 40 grams of protein, 12 grams of fiber. The processed food had just 30 grams of protein and less than six grams of fiber. So that explained some of it, right? And so I guess the conclusion from this is, you know, going back to Dr. Mark hub and his sort of, his sort of, let's just say experiment, that you can lose weight, eating processed junk food is true, but he could have eaten a lot more whole food that had important nutrients and lost the same amount of weight.

Brian (10m 17s):

So I guess if you didn't have enough reasons to avoid processed food when losing weight, add in the fact that your thermic effective food add in the, the fact that thermic effective food to the list processed food takes less energy to digest and absorb compared to whole foods. So a hundred calories of processed foods ends up being more net calories than compared to a hundred calories of whole food. Cause in this example, let's just say took 50% more energy to digest the whole foods. So you net that out and you had to lose, and of the a hundred calories, you had to use about half of that to digest it.

Brian (10m 57s):

So you're only at 50 net calories compared to the processed food, which was minimal energy to digest. So you're getting about a hundred. So if you're trying to lose weight, eat whole foods. If you're trying to gain weight, well eat a little bit more processed foods for a while if you're trying to go, you know, put on weight and, and, and, yeah, I mean, that, that's the, that's the truth. But for most of us, we wanna be eating whole foods. Now what does that mean? You know, you gotta look what's on the ingredient list. How many ingredients is being listed? Do you recognize all of these is a, is a big one as well, right? Can you pronounce the ingredients easy? All these protein bars, just look how many ingredients can you, can you, can you pronounce them as well?

Brian (11m 41s):

And then think about how many steps it took for that food to get to you, right? I mean, n if you're buying steak, fish, you know, fruit, some vegetables, right? How many steps did it take for you to get to you compared to something that's, I don't know, a chicken nugget, let's just say, right? Processed chicken cut up, you know, put it in oils and you know, breaded this and that. Put it in a box. So if it, if it comes in a bag box or can, you know, you could, if you can avoid it, do your best to avoid it.

Brian (12m 24s):

So next time you're in the grocery store, you wanna make sure you look at the ingredients. The fewer, you know, fewer ingredients, the better. You know, just for example, like I tend to buy a good quality like a Greek yogurt, which will pretty much be milk and bacteria. And then there's other yogurts, you know, so-called yogurts which have sodium citrate, corn starch, gelatin, pectin, calcium phosphate, potassium phosphate, sodium phosphate. So a lot a, a lot of things. So look at ingredients if you are buying them, you know, obviously from a box or a can or whatever. And make sure you get the one with less ingredients and I think you'll be better off.

Brian (13m 5s):

So interesting study. Check it out for yourself. I'll leave a show and I'll leave a, I'll leave a link in the show notes, host brandand, energy Expenditure and Whole Foods versus Processed Foods. And I thought this would be applicable. So keep this in mind when you're going to the store. And yeah, thanks so much for listening. If you're loving these micro podcasts, would love a review. That'd be great on iTunes, Spotify, whatever you'd like to wa listen to it or watch it on YouTube. And I look forward to talking with you on Friday for another great interview. Have a great rest of the week. Thanks so much. Thanks for listening to the Get Lean ean podcast.

Brian (13m 47s):

I understand there are millions of other podcasts out there and you've chosen to listen to mine and I appreciate that. Check out the show notes@briangrin.com for everything that was mentioned in this episode. Feel free to subscribe to the podcast and share it with a friend or family member that's looking to get their body back to what it once was. Thanks again and have a great day.

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