Episode 110 Transcript – 6 Things We Have Changed Our Minds On

Leah:

Hello, and welcome to the Ideal Nutrition Podcast. I’m Leah Higl, and I’m here with my co-host, Aidan Muir. And today we’ll be talking about things that we as dieticians have changed our mind on over time. We’re talking about this a little bit off-air just before, and we’re like, well, to be honest, there’s not too much that we’ve drastically changed our mind on as dieticians as we’ve practiced, but there’s definitely a few things that we’ve gained a more nuanced perspective on, and I think it’s definitely worth going over these things.

Aidan:

The first one I’ll start with is talking about muscle and metabolism, where I was a big, big believer that gaining muscle, improving body composition, in terms of either gaining muscle in terms of gaining size or literally just recomping, would have a large influence on our metabolic rate. And starting with why I thought that. Honestly, just a lot of exposure to the bodybuilding world, particularly the non-competing bodybuilders, just recreational bodybuilders, doing the classic bulking and cutting, just seeing so many of them on quite high calories and struggling to eat that amount of food. It was almost like a blessing for them to go into a calorie deficit at time because they’re like, “Oh, I don’t have to eat so much anymore.” So that was really what made me think about this a lot, and I’ll go through from a nuanced take, but I thought it made a big difference.

And then one day, I saw somebody quote some numbers, and they quoted this concept of muscle or lean mass burns about 12 calories per kilo and fat mass burns about four calories per kilo. And if we’re solely looking at metabolic rate, which is what I was talking about, that doesn’t change that much. And I’ve spoken about this on a podcast, but if somebody gained like 10 kilos of fat mass, sorry, 10 kilos of muscle and they lost 10 kilos of fat, that’s an incredible transformation, but it’s only changed their resting metabolic rate by around 80 calories.

The nuance on this, obviously just looking at that, you can see why I changed my mind.

Leah:

Yeah, it’s not that big of a difference.

Aidan:

The nuance and trying to explain why I was seeing what I was seeing. Firstly, the nuance is that what if in the process of doing that you had to train more, you were more active, you’re capable of training more? Somebody who had not been, let’s use running as an example, you’re not going to gain much muscle running, but let’s use that example. Somebody started running and they were only capable of doing, say, 2Ks to start off with, and then they built up to doing 10Ks. Obviously, they’re going to be burning more calories. Same thing with training or if somebody improves their work capacity.

That’s one thing I’ve changed my mind on. Very quickly, coming back to the bodybuilder thing, but even, say, active people to start off with, they train heaps. They’re usually relatively large people. They’re also more adherent with their calorie targets as well. They’re spending longer in calorie surpluses, and there could be metabolic adaptation that’s occurring with that. But I also think the adherence is a big thing because they’re tracking their calories accurately, which would give them a bit of a higher number than somebody who is missing stuff as well. So quite a lot of variables, and even though there’s a nuanced way of looking at that, it is still something I changed my mind on.

Leah:

Yeah, I think once I saw those numbers on just how little your base metabolism changed with a huge change in body composition, I was like, oh, it doesn’t matter that much. But what you then do with that mass and how active you are obviously does change things or can change things quite significantly.

Something that I changed my mind on very early as a dietician is the concept of breakfast being the most important meal of the day. I think that’s probably something that I took from my general day-to-day life and my upbringing and kind of brought into my very early years of practice, and how other dieticians talked about breakfast as well in that everyone should eat breakfast, everyone’s going to benefit from having breakfast. So I used to be a big advocate for that. And if someone came to see me for weight management, so whether they’re wanting to maintain or weight loss and they weren’t a breakfast eater, I would encourage them to add a breakfast meal and start the day with a balanced nutritious breakfast.

But now, after working with a lot of clients, spending years in the industry, but also delving more into the research around breakfast and weight management, I would say it really isn’t as big of a deal as I once thought. I definitely have a nuanced perspective on this, but the fact of the matter is that some people just don’t like to eat in the morning and they just prefer to start their food intake around that mid-morning or even lunchtime. And if that is someone’s preference and they don’t have any issues around binge-eating or overeating later in the day due to that later start in intake, then I’m not going to push them to have breakfast for no reason. I’m just going to be like, okay, that’s their preference, and we can kind of just work around that.

And we’ve actually recently done a podcast on the impacts of having breakfast versus not having breakfast on caloric intake. And we summarized in that episode that most of the research has actually shown an overall greater caloric intake in breakfast eaters or people who add in breakfast than those who don’t. So that’s not to say that breakfast is inherently bad. There’s a lot of different factors to consider there, but it’s just not the big deal I once thought it was. And I’m like, if your preference is to not eat breakfast and there’s no negative side effects of doing so, you don’t have to eat breakfast.

Aidan:

Yeah. I’m going to go with two here because one of them I realized halfway through talking about in the last podcast, kind of shot myself on the foot a little bit, but one of them that I clearly have changed my mind on is the ideal size of a calorie surplus. And there was a lot of things that changed. Actually, maybe I’ll just do this one, but I’ll talk about it from a different lens. I’ve changed my mind on the ideal size of a calorie surplus in that when I first got into nutrition, I spent a bit of time on bodybuilding.com and people were talking about how 500-calorie surplus was like the gold standard, the good starting point. That should roughly equate to, assuming there was no changes in the energy expenditure, which there would be, but assuming there was no change, half a kilo per week rate gain.

Why did I change my mind on it? Two things. One was just thinking about logically, which I’ll come back to, but the other one was very clearly seeing a study that I talked about in the last podcast about how one group of college athletes were given a 500-calorie surplus, a plan that was specifically laid out to be that size surplus, and the other people were just told to eat ad libitum, but eat a little bit more than usual. The people who ate ad libitum had a very good rate of muscle gain in comparison to fat gain. They gained a decent amount of muscle over the course of the study, and they gained a little bit of body fat. The people that were made to be in a 500-calorie surplus gained heaps of body fat and only a tiny bit more muscle. So the ad libitum group just ended up in a much smaller calorie surplus.

And the combination of that and the rate of weight gain thing really got me thinking of being like, well, firstly, 500 is probably too large. It doesn’t increase muscle growth that much for most people. There can be exceptions, freaks, et cetera, but people newer to training, but once somebody’s been training for a while, it’s probably too large, and it won’t increase the rate of muscle that much, but it’ll increase fat gain quite significantly.

But then just thinking about logically, and this is the easiest way to think about it, let’s say you went on a year-long calorie surplus and half a kilo per week, let’s say you’re striving for that target. What is it, you’re looking at 26 kilos of weight gain over the course of a year. If you took a second and just reflected and like, okay, I’m not going to take drugs, but I am going to train hard. I’m going to do all these things. How many kilos of muscle do I think I’m going to gain? It’s like somebody who’s newer to training obviously is going to gain more than somebody who’s been training for a while, but nobody’s really sitting there being like, yeah, I’m going to gain 26 kilos of muscle this year.

Leah:

If I can gain a couple of kilos of muscle in a year, I’m like, yes.

Aidan:

Yeah. And when you look at it from that perspective, you’d be like, oh, it would be dumb to gain half a kilo per week for a year. And then you just scale back that timeline being like, oh, if I was going to do a calorie surplus for three months, that rate of gain would be dumb. So it’d be like, let’s scale that back to a lower number.

Leah:

Yeah, I think in terms of, I’ve probably changed my opinion on that a lot as well in terms of for myself and a lot of my athletic clients wanting to gain muscle, the calorie surplus I use is maybe either maintenance or at most 200 to 300 calories per day. That is kind of the top end. So yeah, no, I’m definitely on the same page there.

The next thing I want to quickly chat about is the concept of 1200-calorie diets. I think from the perspective of being someone in, obviously, the dietetic field and being around a lot of other nutrition professionals, there’s a lot of talk of no one should be on a 1200 calorie diet. That is irresponsible. There’s no place for it. It’s going to harm your relationship with food, et cetera, et cetera. And without delving into it further, I definitely was in that camp to begin with as well.

But since then, I’ve had experiences with a few clients who in order to get a little bit of fat loss to occur, we’ve actually needed to be on that kind of 1000 to 1200 calorie amount, and I didn’t necessarily in that particular circumstance think that was unsuitable for them or a particularly negative thing. Using that blanket statement is not one that I really like to utilize anymore. Specifically talking about the clients I had these experiences with is it was usually already quite small, petite, mostly sedentary women wanting to lose weight. So they were starting at a baseline of maybe their maintenance calories was 1600 to 1800, so by the time we took off a modest calorie deficit, then they were around that 1200-calorie mark, and that was fine. We did what we needed to do and then we went back up to maintenance. So yeah, I think it’s just over time, with experience, something that I’ve kind of nuanced my stance on rather than having the blanket statement of ah, it’s suitable for nobody.

Aidan:

Yeah. I’ve also came to the same conclusion. An example that I often use on that is say I were to maintain on 3000 calories per day, and I went to a calorie deficit where I was eating 2000 calories per day. Nobody thinks that that’s horrific. Nobody’s like, “I can’t do that.” It’s a large calorie deficit, but a lot of people are okay with hearing those numbers. What if somebody’s maintenance calories was 1,600 because of those reasons, like they’re smaller, relatively sedentary, et cetera, et cetera. When we look at that, it’s like if they did a 600-calorie deficit, it’s not that different to the extent that-

Leah:

It’s like a similar percentage relative to their maintenance calories. It’s the same. It’s just our thoughts around that specific number.

Aidan:

That number, yeah. On an unrelated note, but every now and then I get people in my DMs being like, “Oh, I’ve been reading that I need to eat 1,200 calories or less to lose weight”, and I’m like, we are living in different worlds.

The bubble that I live in, everyone’s saying, “You should never.” Where is this info coming from?

Leah:

Sometimes I forget because yeah, we’re not often exposed to that because they’re just not the people we are following.

Aidan:

Yeah. This does actually lead into a point that I’ve changed my mind on and I’ll explain why. So rate of weight loss having a huge influence on rate of regain. I used to believe quite confidently that slow and steady wins the race. I do still believe that if you took a very deep look at the research, you could make an argument for slightly slower rates of weight loss improving the odds, right? I do believe that. But the thing is, I used to believe it had a huge influence. That’s the thing I’ve definitely changed my mind on. Explaining a few things. The first thing that made me, and we have talked about this very early in the podcast, I believe, but the first thing that really prompted me to be like, “I probably got to rethink my stuff a little bit,” was that there was a study that involved an 800-calorie diet for 12 to 16 weeks for people with diabetes, type 2 diabetes, and a lot of people lost over 15 kilos, no longer needed medications.

The remission rate was somewhere around 30-something percent, and the control group people tried slow and steady weight loss, they were referred wherever they were referred by their doctors, and 2 to 4% went into remission. And it’s like, okay, so they got much better results. Why did that happen? And also, was this maintained? And why did it happen, one thing was there was a very kind of intense protocol where they had a lot of communication with doctors. They did have dieticians, they had other allied health around them. They did shakes for the 800-calorie diet. When they transitioned away from that, they took away a shake, they added a meal, then they took away another shake, added a meal, over about a six-week period of reintroduction, which no one in the real world is really going to do that. But it leads into a point I’ll come back to.

And was there follow up? Yeah. The two-year data showed that on average people were regaining weight, but at the rates that other people were regaining weight to start off with in pretty much every other study, which means that they were still down considerably more.

If you’re looking at non-medical, non-bariatric surgery or medication studies in terms of weight loss medications, if you’re looking at those studies on diabetes, this study actually had, and it was very large sample size, it outperformed pretty much every other study we’ve seen on diabetes management. And it’s like if everybody had a blanket people-can’t-go-on-low-calorie-diets-ever statement, that could never be done on anybody. That’s where I’ve softened my stance. So that’s one thing, but talking about the other way of thinking about it is that it’s not necessarily what we do on the way down.

After seeing that, has it changed my mind to the point, it’s like I get people in and I put them on 800-calorie diets? No, I’ve never done that. I’ve never actually implemented anything like that. I have no interest in implementing anything like that, but it is food for thought, and the very obvious thing is it’s actually not what we do on the way down. It’s what we do after. What did they do that differed to what other people do? They took away a meal or they took away a shake, added a meal, and they had a structured reintroduction of food.

By definition, being in a calorie deficit is different to being at maintenance calories. Somebody who goes into a 500-calorie deficit, when they get to the end of it, assuming they’ve been adjusting their diet, has to increase their calories at the end to maintain their new body weight. Somebody who went into a 1000-calorie deficit, it’s twice the deficit, they have twice the amount that they have to add back in at the end, but the key thing is it’s like when you get to the end, what do you do then?

And how much does what you do on the way down influence that? You could talk about that for ages, but it’s just an interesting thing to think about just being if some… Oh, actually the last one I was going to add on this is why do we inherently think that slow and steady is the way to do it? And I think something that makes us inherently think this is, firstly, we hear people say this, but then we look around us, and we see a lot of people lose weight quickly and regain weight. And this was one of the biggest things that kind of challenged my belief on this is that it’s not just people who lose fast who regain weight. People who lose slow often regain weight, too.

A point I often make to some clients is can you name two or three people in your life who’ve lost weight slow and steady and maintained that weight loss? And a lot of people can’t. It’s like we’re not seeing a lot of either of these things happening. It’s just when people lose weight quicker, it’s more noticeable when we see it happening. But it’s like somewhere along the lines of 80 to 95% of people who lose weight regain weight anyway. And the bigger question is how do we improve those odds significantly. I think that’s less to do with the rate of weight loss and more to do with all the other stuff.

Leah:

Yeah, I love that. That’s a good one.

Last one I’m going to touch on today is probably more like plant-based specific, but talking moreso around soy. When I first started operating in the plant-based space years ago, I kind of looked at the overall research and I was like, look, systematic reviews on soy intake shows that there is really no significant effect on human hormones with a moderate to even slightly higher soy intake. I still think that is true to a certain extent, but I’d also say my opinions are a lot more nuanced now. And I think having that kind of blanket statement there is kind of missing the forest for the trees in that I think there are specific cases where it does impact human hormones. And if I was to say, “Soy has no effect on human hormones,” I think that would be a false statement.

So soy contains something called phytoestrogens, which is a plant compound that is very similar to estrogen in the human body, which is the female sex hormone. And whilst phytoestrogens don’t have the exact same impact as, say, taking estrogen in the kind of human form, it does have a similar effect on the body just to a much weaker extent and only in kind of more specific circumstances. So places where we see soy having an impact on human hormones is A, in premenopausal women. Phytoestrogens can actually have a somewhat estrogen-blocking action for the most part. This doesn’t really mean much in regards to outcomes, but there is a handful of case studies of some women who had really high soy intakes and because of this estrogen-blocking action, they actually ended up losing their period or their period was irregular, and they were having trouble falling pregnant. And then once this soy intake was reduced or taken away, then these issues all of a sudden resolved.

There’s a lot of nuance to that discussion. Probably could do a whole podcast on its own, but even though it’s only a handful of case studies and not the broad impact of soy intake in general, I think it is going to be relevant to some people in some circumstances, and there are some people who are more sensitive to very high soy intakes.

Another aspect we could look at this from is in post-menopausal women. So it actually has the opposite impact in post-menopausal women, where we can actually see an increase in estrogen levels having a beneficial impact on menopausal symptoms that specifically come from a drop in estrogen as we go through this part of our life. So something that has quite a lot of research is the impact of phytoestrogens on hot flushes and that actually reducing the amount and severity of hot flushes in post-menopausal women. And this is because, to a certain extent, these phytoestrogens and soy do impact human hormones to a certain extent.

And then last thing I want to touch on is in severe cases, I mean, we only have one or two case studies, but there have been some feminizing effects seen in men, drop in testosterone, an increase in estrogen, from very, very, very high intakes of soy. Again, these are way outlier situations, but I still think it’s all of that is worth recognizing and having that nuanced view, I think, just makes my arguments more credible when I say that yes, I recognize all of these impacts. It does impact human hormones to a certain extent, but just not in other ways that we may think.

Aidan:

Yeah, it is a tough one. We wish it was simple.

Leah:

I wish it was more simple because I understand where this fear around soy and its effect on hormones came from and it’s like it came from this seed of truth, and it was blown out of proportion, but I still want to acknowledge that seed of truth.

Aidan:

Yeah, exactly, because there is fear that people are like, if I have tofu once or soy milk once, this is an issue.

Leah:

Exactly, where that’s obviously not the case, but there are outlier situations where we are seeing these impacts.

Aidan:

Yeah, for sure.

Well, this has been Episode 110 of the Ideal Nutrition Podcast. As always, if you could please leave a rating and review, that would be massively appreciated.