On this episode we talk about whether exercise is useless for fat loss and we go down and dirty on Ultra Processed Foods.
[0:00] - Introduction
[0:43] - Is Exercise Useless for Weight Loss
[15:38] - Ultra Processed Foods
00:02
Welcome back to MI Take, a podcast that discusses current events in nutrition, the business side of the health and fitness industry, and a little bit of everything in between. Today on the show, we're going to be talking about the recent discussion about whether exercise is useless for weight loss and the role of processed foods and whether they're actually just fine or if we should consider reducing how much we consume. Let's get into the show.
00:43
All right, diving straight into the first topic today, we're going to be discussing this concept of whether exercise is useless for weight loss. And I'm kind of doing a little bit of a inflammatory opening specifically just to kind of kick this conversation off. This is primarily coming from there was a recent interview on the Renaissance periodization YouTube channel between Mike Isretail and Eric Helms. And
01:12
What was interesting was there was a ton of questions in the Facebook group about the episode and some statements that were made. And so I went and actually watched it. And what was really interesting is what I took from the episode was substantially different than a lot of the questions and kind of the vibe I got from the comments in our Facebook group about this. And so I wanted to do a little bit of a
01:40
I don't want to say a deep dive, because I'm not going to go fully in depth. I'm actually going to try to get Eric on the show and just kind of expand some of the topics. I think he was on there for like 25, 30 minutes. And I think there's a couple hours worth. I'm not going to steal several hours worth of Eric's time. But I'd like to get him on the show, because there's a few points that I really wanted to kind of just dig into, because I think there's a lot of interesting stuff. And then apply it to clients like ours that deal with some of these things. So I want to start by.
02:09
I'm just saying I would say I agreed with probably 98% of what was discussed in that episode and I think maybe the things right? I don't know if I disagree but just had maybe like some context I'd love to pull out of that conversation and so I want to talk I want to provide some very basic overviews of what was discussed and Then kind of dive into some of the additional insights that I want to just try to tease out because I think it's
02:39
there's some important nuances to the conversation. So the conversation was basically around this idea of the constrained energy model versus the additive energy model. And to put this very simply, the additive energy model goes something like this. If your normal daily life is you burn 2,000 calories a day and you add 500 calories of exercise, your new total daily energy expenditure is on an
03:08
everyday repeatable measure, 2500 calories. That's the additive model, right? You just add the exercise calories to your everyday calories. The constrained energy model, as it's shown in graphs, kind of has this feeling of, hey, actually your body's only going to burn a certain amount of calories, and if you exercise, your body is going to compensate everywhere else to only burn a certain amount of calories.
03:38
right so the analogy that's often painted is hey if your normal total daily energy expenditure is 2,000 and you go exercise 500 well everything else is going to compensate down 500 so you're only going to burn 2,000. One I don't think that's realistically how that works and two I don't think that's what the theory actually states. I think and based on the conversation that Eric had with Mike
04:06
was what they were trying to say is, if you burn 2,000 calories on a daily basis from all of the things you do, right, your basal metabolic rate, your thermoconfective food, your NEAT, so your kind of non-exercise activity, and your exercise, if you add a substantial amount of exercise, your other physical activity in your life, specifically your NEAT, is probably going to drop
04:36
and you're not going to see that full 2500 calorie expenditure. It's probably going to be something like let's call it 2400, right?
04:45
In addition to that, the other aspect of it is we lose some efficiency as we increase our exercise. So let's say you go from 0 to 500, you probably are actually burning maybe closer to like 4, 450. As you go from 0 to 1,000 or 500 to 1,000, you're probably burning 850 to 900 instead of the full 1,000. So you kind of get this loss of efficiency.
05:11
with movement as it goes up. This is why going from 0 to 10,000 steps probably gives you more of a return on the investment of the steps and going from 10,000 to 20,000 and then 20,000 to 30,000. And what Eric was trying to say in the show, at least I think this is what he was trying to say, is we just lose efficiencies as we start to exercise more and more and more and more and more.
05:37
Like whether it's a metabolic efficiency, a biomechanical efficiency, there's still some unanswered questions. But basically, our return on investment goes down. I think that's totally reasonable. And I think that's actually something we see across pretty much everything that we do. We see losses of efficiency in pretty much every physiological system we have. We can even think about this on the other side of the spectrum.
06:05
So what happens if you overeat your total daily calories by a thousand calories? You don't actually net that full thousand you actually start to lose some of that due to you know heat metabolic inefficiencies Etc like maybe it's 750 net calories right so we see these just losses of efficiency all across the board and so I think this is true and While I believe that this is true
06:35
I am not 100% sure how this relates to most of us in our everyday lives, other than the fact that I think we probably overestimate the total daily calorie expenditure we get from adding exercise. I think that would be abundantly true.
07:03
how much adding substantially more exercise affects the other parts of our lives, right? So I think if you go from not exercising to exercising five days a week, that probably has a pretty large net benefit on your total energy expenditure over a week. If you go from five to seven, I think you probably get slightly less return on investment for the total energy expenditure.
07:32
Now the other side of this that I do think is something that should be discussed in probably more detail, and I'd love to pick Eric's brain on this, is this idea of exercise, physical activity, NEET, and the constrained energy model. And he talked about this a little bit of when we're in a deficit, how this affects this. And this is one of those areas where...
08:01
Most people are going to add exercise as a way to help accelerate weight loss when they're in a deficit. And my view on this is I think exercise and increasing step count is less about increasing total daily energy expenditure above what you were before, and it's maintaining total daily energy expenditure in the presence of...
08:29
calorie deficits. And so it was really interesting is they mentioned the work from Leibel and Ravison who they basically talked about, hey you start to lose efficiencies as you as you exercise, your change in substrate metabolism changes, and these are the same people that did the research showing basically what happens when you go into a diet, right? As you're in a calorie
08:59
And that changes in need often explain why some people lose weight versus don't lose weight or gain weight versus don't really gain weight based on overfeeding and underfeeding. And so I think probably what we see in reality for a lot of people as we think about this idea of constrained energy is I think the concept of if you're just trying to lose weight by just adding exercise, you're gonna see a ceiling of
09:28
how much you can actually increase your total energy expenditure, and you're gonna have a relatively small cap on the total daily deficit you can accumulate, right? If you can add 400 calories a day of exercise, that may be constrained to actually like 200, 300, right? So that's fairly small. You're gonna need diet to drive the other pieces of that. And on the flip side, I think a lot of times what happens is when people go
09:56
to just diet alone and use relatively extreme approaches where they decrease intake by a thousand calories a day, I think their total daily energy expenditure is reduced substantially unless they have, you know, very specific physical activity goals, whether that's exercising at the gym or they're neat. And my thoughts on this would be, hey, for the people who are attempting to lose weight by just using exercise, this is something that you should be...
10:25
very aware of is you're probably not getting the actual total energy expenditure you are assuming you are getting because of these things and that you're going to have to use some sort of calorie restriction to get a meaningful enough deficit to where you can make meaningful progress in weight loss. And this actually plays out in all of the diet and exercise literature and basically every study ever done where they've compared diet.
10:52
exercise or combination of diet and exercise. Exercise alone is the worst tool for weight loss, just by itself. Diet is better. Both together are ideal. And I think it has more to do with the exercise preventing the diet reduced total energy expenditure that you get from kind of the reduction in physical activity that generally occurs with people when they diet.
11:23
And then this brings me to the last kind of two points and concepts that I think are important just to remember and keep in the back of your mind is, is twofold. One.
11:37
The calories you expend from exercise are not really the goal. The goal of exercise is to send signals to your body to adapt, right? Doing cardio for an hour, hour and a half, the calorie expenditure you get from that is relatively negligible, right? It's probably a couple hundred calories if you're doing moderate intensity, maybe 300, maybe 400, maybe 500, right? That's negligible when you think about the fact that a slice of pizza alone is usually
12:07
400 or 500 calories. And so what exercise is doing is it actually is just giving you adaptation signals. So it's telling you to have a more robust cardiovascular system, it's telling you to have better glucose management, it's telling you to have stronger muscles, it's telling you to have denser bones. And that's the primary benefit of exercise. The other aspect to it is it allows you to maintain a meaningful calorie deficit
12:37
at more realistic calorie intakes. Right, if you don't do any physical activity and your total daily energy expenditure is 1800 calories a day and you wanna lose about a pound a week, trying to survive every day for extended periods of time on 1200 calories for most people is just not reasonable. Right, now if you add.
13:00
300, 400 calories a day of exercise, well now all of a sudden you can eat 1,500, 1,600 calories and still have the same level of deficit. And if we look at the literature on dietary adherence at various calorie intakes, we know that as you get to very low calorie intakes, adherence drops off fairly meaningfully. And so I think that's the other important piece to remember is...
13:27
The exercise also provides you with a level of meaningful calories that you can consume in a day and not feel restricted. So I think there's a lot of layers to this that are really interesting. And this is one of the benefits of really trying to pay attention to the levers that you can pull in your life and why you're pulling them and really understanding what your goals are. Right? If pure weight loss is the goal.
13:55
Obviously, diet's the biggest lever. Exercise as a lever helps you maintain muscle mass as you're losing weight, helps you regulate appetite, helps you regulate mood, helps you build better bones, helps you improve your cardiovascular system. That's a lever that has to be pulled as well. Your NEET, just your general physical activity as a lever is a way to prevent kind of the...
14:24
diet-related decline in total energy expenditure. And so these are all things that we should consider. And so I think when we talk about this idea of, hey, is exercise useless for weight loss, in some sense, it's pretty inefficient. But that doesn't mean it's not important, especially when we think about it as a whole context of a person's life. These are actually meaningful things to consider. So I thought the conversation that they had was great. I thought it was
14:53
very illuminating for a lot of people to understand how our body actually works in environments and not just this math in, math out model. And I thought they did a really good job discussing it, and I'm hoping I can convince Eric to join me here. I actually already convinced him to help me with another project this summer, so hopefully I can borrow a few more minutes of his time. So we'll take a quick break, and then we're going to come back and we're going to talk about processed foods. And apparently they're having a heyday right now, so we've got to revisit it.
15:40
U-P-Fs, ultra processed foods. For some reason, this is making another round in the Facebookosphere, social mediosphere, Instagramosphere, podcastosphere. I'm just making up words now. But this is a topic that has come up several times in the last week. And there's been some really interesting takes on it.
16:08
Some that have been really good, some that have been really bad, some that have made me laugh. And what's really interesting is I feel like people both oversimplify this and under-simplify this topic.
16:26
way too much. And I think we need to give it really the, I don't want to say the respect it's due, but like the time that it's due to really kind of chew through some of the important pieces, but also understand what the actual context is. So let's break this down into a few core concepts. The first concept we're going to talk about is the effect that ultra processed foods have on calorie intake and body weight.
16:57
Ultra-processed foods by themselves are not inherently more fattening or prone to weight gain than a non-processed food. From the perspective of just because these are processed foods doesn't mean that you necessarily extract a meaningfully more amount of calories from a gram of ultra-processed food than non-processed food.
17:25
Yes, there's some differences in how many calories are extracted, the efficiency, et cetera, but per se, they are not inherently more fattening. However, ultra-processed foods tend to make us over-consume them, to which we consume more calories. This was beautifully illustrated in a study that was done.
17:52
at the National Institute of Health by Kevin Hall's group, who he's now become what I would say, probably one of the leading researchers in understanding the fine details of nutrition, metabolism, weight loss, metabolic efficiencies, macronutrient-based diets, et cetera. And I don't have this study pulled up in front of me just because I've read it so many times. And basically what they did is they put people in a metabolic ward.
18:22
They tracked everything they ate. They gave them the ability to consume as many calories as they wanted. And for a while, they put them on a minimally processed food diet. And then they put them on a ultra processed food diet. And the short version of that story is if you give people ultra processed foods, they are generally more energy dense. They generally have more salt, sugar.
18:48
They're generally more palatable, which means how much enjoyment and reward we get out of eating that food. And all of those factors cause us to consume more calories, somewhere in the neighborhood of 500 to 1,000 calories a day. This is fairly well known. This is something we actually see that plays out in the real world. Like if you give somebody a processed food diet and you ask them just to consume freely, they're gonna consume more calories.
19:17
So it's the energy density and the palatability of these foods that drives over consumption, which drives weight gain. This is fairly well understood. So when people say things like, hey, it doesn't matter if you eat unprocessed foods or processed foods, they're the same, but processed foods will make you eat more. That's what they're talking about, right? Is...
19:45
These ultra-processed foods are not inherently more fattening per se, but they do cause us to consume more calories. But that's a very important distinction, especially when we talk about real-world applications.
20:00
Having somebody consume a diet of completely discretionary foods, of ultra processed foods, unless you are meticulous about tracking, calorie counting, portion control, it's going to be much harder to control your total calorie intake if your diet is entirely processed foods. So this is why the advice of, hey, eat more whole minimally processed foods generally tends to lead to weight loss because it's much easier to control your total daily calorie intake.
20:30
if you're doing that. And this is the exact reason why, maybe a year ago, maybe five years ago, time doesn't mean anything to me anymore. But I put out a post on Instagram, I think, and it was something like, if you are religiously tracking your calories and your macros, food quality doesn't really matter that much. If you're not tracking your calories or your macros, food quality matters a lot. And it's this idea of, if you are just free eating,
20:59
These ultra-processed foods are going to increase the likelihood that you consume 300, 500, 700, a thousand more calories a day. So that's the first topic. The other topic that we definitely need to discuss is the quality of these foods is something that we need to consider. So when people say, it's fine if you eat a diet of, you know, entirely...
21:27
ultra processed foods, as long as you control your calories, you're gonna be fine. I think that really misses the mark on what's true. Yes, it's true that if you maintain a regular BMI despite eating ultra processed foods, you have much lower risk of all cause mortality, cardiovascular disease, cancer, diabetes, stroke, et cetera.
21:56
than somebody who eats a quote unquote healthy diet, but has a BMI of 40, right? That is objectively true. But that doesn't mean that the ingredients in the food that we consume don't carry risk. And we know that this is the case because we've done these studies. We've done intervention studies, we've done observational analyses. You know, we've done a lot of work to understand this. I do think there is a little bit of
22:26
over demonization, fear-mongering of these things, but I think to say they have no risk is not fair and I don't think it's accurate. The best example of this is trans fats. It's very rare that we get very rapid agreement among scientists about the effect of an ingredient on overall health.
22:52
The idea of trans fats being healthy to unhealthy went relatively quickly in the scientific sphere, right? Initially they were sold, they were great, they were healthy, and then all of a sudden all this data started coming out and pretty quickly we changed our tune and we actually have now put them, we've removed them from the generally recognized as safe ingredient list. So generally speaking, ultra processed foods do have higher concentrations or amounts of trans fats in them.
23:23
The FDA has made some declarations to food manufacturers that trans fats need to be eliminated from the food supply, but they are still present. And even small amounts of trans fats, I'd have to remember the exact number, but I think it's like even 2% of total daily energy coming from trans fats is enough to increase your risk for cardiovascular disease by a meaningful amount.
23:49
I actually included this in a review paper that I published, so I should know this like the back of my hand, but it's been nine years now since that paper was published, so I'd have to go look at it, but it's something like every 1 to 2% increase of total energy expenditure increases your risk of cardiovascular disease by a meaningful amount. So that's one. We also know that ultra-processed foods generally tend to be higher in things like sodium,
24:17
They tend to be higher in things like saturated fat, and they tend to be lower in things like potassium, magnesium, et cetera.
24:25
If we think about the context in which these foods are consumed, these things start to actually matter. And let me paint an example with sodium. We as the scientific community know, or actually I should say are fairly confident that unless you have hypertension or established cardiovascular disease, dietary sodium doesn't have a meaningful impact on overall cardiovascular disease.
24:55
if you are otherwise healthy and have no pre-existing conditions. However, if we look at what the average person in the United States is, the average person would qualify as being at risk. They would fall into a high-risk category who probably needs to regulate and control sodium. I think right now we have more than, I'd have to go look at the statistics. I think it's over 60% of people.
25:23
would be considered having overweight. Almost 40% of people would be considered having obesity. I think as of 2017, the data indicated that more than half of American adults would have been diagnosed with hypertension. So the average person actually falls into this high risk category. So them consuming a, you know, highly processed food diet,
25:51
even if they control calorie intake, is something to consider. Right? So just because something like sodium may not be an issue for the otherwise healthy, the average American adult, this is something they need to pay attention to. Right?
26:10
And so you have to think about these in the context of why this matters. And so I think the way that we think about this is
26:20
When you think about the context of your diet, including some amount of ultra processed food is probably not that big of an issue. Right, if you have 10% of your calories a day are discretionary and they come from ultra processed foods, you maintain calorie balance or a calorie deficit. They are not driving you to over consume. You are losing weight, your body weight's going down, you're maintaining normal blood pressure.
26:49
your metabolic panel is fine, these things probably not a cause for concern.
26:59
If these are making up 30, 40, 50% of your diet, and you're somebody who is otherwise at risk for developing chronic diseases, or you have chronic diseases, these things definitely need to be reduced and, or eliminated from your diet as much as possible and try to keep these to the sub 10% of discretionary calories. And so this is one of those nuanced things in nutrition where
27:28
hey, this doesn't matter, but it does matter. And how much of your diet it consists matters. What your overall health and metabolic state matters. And I think saying that, hey, as long as all calories are equated for, it doesn't matter the quality of your food.
27:52
I don't think that's a super accurate interpretation of the literature. On the other side, we probably don't need to overly demonize things either. I think it's a, you have to find the balance of what's true and what's reasonable and then how do we actually operationalize these into people's lives. This is why I have no problem having a couple of Oreos every once in a while. I have no problem.
28:22
you know, eating a maple bar once a year. These are why I have no problem going to the movie theater and housing a large popcorn when I go watch the Dune II premiere. I did not get the weird bucket. Don't even think I got the weird bucket. That was a very weird bucket. But these are all things that are, they're part of life. Understanding the context of them, making sure that these things fit into your overall plan is important. So.
28:51
I hope this episode was helpful. This was filmed last minute. I actually was just thinking about this while I was at the gym, so I made a bunch of notes on my phone and then came home and immediately recorded it while I was all sweaty and out of breath. So hopefully that was enjoyable. We have another episode scheduled to go out later this weekend. I'm Dr. Brad, I'm outta here. I will see you guys next week.