Episode 120 Transcript – Thoughts on a Wholefood, Plant Based Diet

Aidan:


Hello and welcome to the Ideal Nutrition Podcast. My name is Aidan Muir and I’m here with my co -host Leah Higl and this is episode 120 where we are going to be sharing our thoughts on a whole food plant -based diet. So this is basically a Leah episode. I was choosing which topic so I was like we haven’t done a Leah episode. Let’s chuck one in.

But no, it’s actually a topic that I’m genuinely interested in as well because it’s taking the whole plant -based approach like another step further. And there’s some interesting benefits there and there’s also some interesting downsides there. So we’ll talk through it.

Leah:

Yeah. So let’s talk about what it is. So it’s pretty much what it sounds like in regards to a whole food plant -based diet. So it limits and exclude, limits or excludes depending on which route you take animal products, so it usually is a vegan diet. And it also looks at reducing and limiting processed foods. So that’s kind of like the whole food portion of it. There are lots of different variations of a whole food plant -based diet. One that is particularly popular, specifically in the space that I work in, is the whole food plant -based no oil.

What a name. And that does take it a couple of steps further where it takes that kind of initial philosophy of eating predominantly whole foods that are plant -based and then also adds in the exclusion of oils as well as eating any other kind of even minimally processed higher fat foods like nuts, seeds and avocado. So it takes this concept of energy density and basically excludes anything that is like too energy dense.

There are, like I said, so many variations, but I think something to note is that they do all prioritize minimizing or even completely eliminating refined sugars, flours, and processed oils.

Aidan:

I love how the acronym, when you write it, because we’ve got that notes in front of us, and like this is written down, the acronym is W -F -P -B -N -O. And they’re all like single. They’re all like whole foods, plant -based, no way. Like it takes the same to say it as it does to do the acronym.

Leah:

Yeah, the acronym’s easier to write, but it’s not easier to say.

Aidan:

So it’s hard to reference research on this topic for a few reasons. One is that you can find a lot of research going through the benefits of adding more plant -based foods and focusing on minimally processed foods and how that could be beneficial for health just in general. I think it would be overkill and redundant to basically spend heaps of time going through that. And because I want to try and keep things a little bit interesting, I’m just gonna go through one study to talk about the benefits and everything like that, and then we’ll kind of come back and go through pros and cons.

And so the main study that I think is interesting and a lot of people talk about is called the Broad Study. And it was a whole foods, plant -based diet, random -must -control trial with 65 people. They had to have above a BMI of 25 to be included and they also had to have a comorbidity like diabetes, hypertension, high cholesterol, heart disease. So that way they’d be looking at weight loss obviously, and they’d also be looking at some secondary health improvement as well, or multiple secondary health improvements.

Of the 32 in the intervention group, 23 people completed the study. I always like to add that when talking about any form of restrictive approach because if we only looked at the 23 who completed the study, we might get an unfair representation. Taking this study out of the example, if 100 people were in an intention to treat group and only 20 people completed it, it would kind of be unfair to just look at the 20 people, because it’s like, what about the other 80 that kind of failed? It’s really like survivorship bias kind of thing. Not as relevant here, but still worth mentioning.

In the intervention group, participants attended meetings twice weekly for 12 weeks and followed a non -energy restricted whole foods plant -based diet with also limited oil as well. And they also took B12 supplements as well. The specification of non -energy restricted doesn’t mean that they were made to eat maintenance calories. It basically just means that they were eating ad libitum. They weren’t told that they had to restrict to any certain amount of foods or anything like that or any calorie targets.

They also went through cooking classes and there was nutrition education included too amongst other supports. So there’s quite a lot of support included, which is probably a big factor in why they had the results. At the end of the 12 month timeframe, keep in mind that the intervention was actually only 12 weeks, they had maintained a loss of 11.5 kilos and the control group had a minimal change from memory was about three kilo loss at the end of the 12 weeks. I’m not sure what they were at the end of the 12 months.

But firstly, using the 12 month variable, I like that because often people do a restrictive approach and then regain weight. So to see that they maintain the loss of 11.5 kilos at the one year mark, that’s pretty huge. Researchers said, there was this quote, to the best of our knowledge, this research has achieved greater weight loss at the six to 12 months mark than any other trial that does not limit energy intake or mandate regular exercise. And I don’t think that is that hot of a take. No studies come to my mind that achieve results like that without some form of restriction in terms of intentional calorie restriction or specific amounts of foods, et cetera.

They also said that they encourage starches such as potatoes, sweet potato, bread, cereals, and pasta to satisfy appetite. But the participants were asked to avoid refined oils, their words specifically, e.g. olive oil or coconut oil and animal products. They discouraged high fat plant foods such as nuts and avocado and highly processed foods. And they encouraged participants to minimize sugar, salt and caffeinated beverages.

So they did take it that kind of extra step of like pretty much no oil. Interesting that it’s like they like refined it was like olive oil. Extra virgin olive oil is literally like just pressed olives. That’s all it is. Not that refined. But they like, yeah, so like it’s funny that that was the example of this is anyway.

But they also did discourage those nuts and avocados, which are higher calories. So they took it that step, however, being like a lot of people think of them as like healthy fats that are also relatively high in fiber, but they were still discouraged as well.

Leah:

Yeah, it’s very much a restrictive diet. Even at its like base level, it’s still very restrictive. And then you add in like the no oil limit, high fat foods of all kinds, it becomes very, very scarce in than what you could eat. But what we want to talk about now is basically the pros and cons of this diet. Obviously that study was from a weight loss perspective, quite promising, but I’m sure you can kind of guess that there are some cons to this diet. There are some things that we guess are like, maybe not so much in favour of, but we’ll go through it and just try to kind of hit it from a pretty even perspective.

So the first thing, like I said, on from like a pros perspective is the weight loss. This style of eating does take volume eating to whole new levels. So it really does prioritize the intake of very low energy density foods, which will likely result in a calorie deficit just by default. So without, you know, intentionally limiting calories, by calorie tracking or whatever the case may be, you’re likely to end up in a deficit if you are just focusing on really high volume, high fiber foods and limiting anything that is quite energy dense and also limiting processed foods and refined sugars and oils and whatnot. So from that perspective, it seems to be that’s quite a good pro.

Aidan:

Yeah, and it makes it interesting because we’re obviously in the concept of restriction, but like it makes it interesting concept of being like it’s restrictive in the form of you have to limit the types of foods you eat. There’s also, you could see this freeing in a way for certain people where it’s like you could have an unlimited amount of anything else.

Leah:

Yes. And it’s like, you may not have to track calories or something that you really keep doing.

Aidan:

Yeah. Other stuff, as I touched on with like improvements in health in terms of like most people increasing plant -based intake and also minimizing processed foods, improvements of health in health often, but not always come alongside that. We’re looking at certain markers such as like cholesterol, blood pressure, blood glucose levels, also looking at heart disease and certain other markers of health, you’re likely going to be seeing huge improvements in that as well. There’s heaps that we could talk about in that, but once again, if you opened any Whole Foods plant -based study, you would expect to be seeing improvements in all of those markets, basically.

Leah:

Yeah, and that kind of leads into our next point that this particular dietary approach does cut out a lot of foods that if over consumed can be detrimental to your health. So we know that having a diet rich in plant based whole foods would clearly be better than what a lot of people are currently doing at baseline.

Aidan:

And something that I’m awfully conscious of is that the average person doesn’t eat enough vegetables or just enough fruits and vegetables in general. And every time I try to talk about something, I try to think what would somebody on the other side, like what would somebody who’s like really for this diet think of me? And if I went in and like ripped on this a little bit too hard, they could look at that and be like, that’s wild that you’re doing that considering like most people would benefit from more fruits and vegetables. And having an approach like this would kind of force slash really encourage you to increase intake of fruits and vegetables in general.

Leah:

Yeah. And then lastly, from an environmental perspective, we know that a low intake of animal products and processed food is going to be more sustainable environmentally, especially when you’re eating like seasonally and locally and avoiding packaging and that makes this a lot easier. So as Dietitians, like some of us care about environmentalism, some of us, it’s not a huge thing in our practice, but I think it’s something worth mentioning.

Aidan:

Yeah. So the next one is talking about the cons. So, I want to start with probably not the biggest one, but just the first one that comes to mind is if it was extended to no oil, that would exclude the benefits that we see from extra virgin olive oil. It’s not the thing I’m the most passionate about, but I’m semi -passionate about it. And when I say I’m semi -passionate, what I mean is we see a lot of research showing improvements in things like heart health, inflammation, even depression and just mental health from studies that include a decent amount of extra virgin olive oil.

Almost every form of research you hear that involves the Mediterranean diet and the health benefits of that, they’re including quite high amounts of extra virgin olive oil. A lot of Mediterranean diet studies include 50 ml of olive oil. And that’s kind of where I talk about my semi -passionate stance being like, I’m really big on the benefits of extra virgin olive oil, but every now and then, not every now and then, I do see a lot of people in the Dietetics world who really promote olive oil to that kind of level of being like, Mediterranean style diets do that, they have 50 ml of extra virgin olive oil.

Where I kind of am in the middle, I’m like, that’s almost 500 calories of extra virgin olive oil. We’re looking at 400, 500 calories. And it’s very different in the context of people who have minimal calories coming from elsewhere, like in the Mediterranean diet, they don’t have a bunch of like, quote unquote, junk food or anything like that. They do drink alcohol in small amounts. If they took out the extra virgin olive oil, they would end up just not consuming it calories overall. Bit of a different context, but I see a bunch of benefits from that. If you completely suited something like this, you could miss out on some of those benefits.

Leah:

Another con is looking at people who are just not wanting to lose weight or people that have like higher caloric needs. Like when you’re eating whole food plant -based, particularly if it’s no oil, you might have to have like a really excessive food volume and a really excessive fiber intake in order to meet your calorie requirements to the point you are getting satiated prior to kind of getting anywhere near your calorie requirements.

Like I work a lot with vegan athletes and when I see them take this whole food plant based approach, they miss the mark on their energy requirements probably like 99 % of the time if they’re following this approach quite religiously. Cause I think a lot of people do find like they start to get really into the culture around this specific way of eating and become very attached to it so they can get really intense with how they like to follow it. And then they just end up under fueling and that leads to a whole host of problems.

Aidan:

And that study, the broad study that I was talking about, it’s kind of set up in a way that really sets the diet up for a bit more success because one, BMI was above a certain level so they made sure everyone who started the study had weight that they could justify blue lose over that 12 weeks. There was nobody who was like in a situation where they’re already quite lean. And two, as I said, they didn’t mandate regular exercise as well, which definitely means if you added in a decent amount of exercise, it could contribute to under -fueling as well.

Other downsides, so can be excessively high fiber, which could lead to GI symptoms, so gastrointestinal distress, not to mention the huge food volume as well, just being like if you did have decent calorie requirements, you have to eat heaps of food to get there. Like one portion of the bloating could be due to the fiber. The other portion could just be this feeling of just being constantly full as well.

Leah:

Yeah. And then you’ve got the FODMAPs and it’s like, it’s all happening at that point. And again, I see that a lot in my practice and my clients who follow this kind of diet. And they’re like, why am I so bloated all the time? I’m like, I wonder.

Another con to this is obviously we’ve talked about the restriction that it does add, but then looking a the link with disordered eating in plant -based and vegans and the vegetarian people is already quite high that I think if you’re adding in more restriction and if there’s potentially kind of a disordered eating risk, I know you’re kind of playing with fire there, particularly if there’s kind of concerns around like body image and other disordered eating patterns. I don’t think it’s necessarily something that’s gonna be beneficial for those people at all.

Aidan:

And another point is that FODMAP thing you raised, what if you had intolerances, like for example, what if you couldn’t eat legumes because of FODMAPs? What if you couldn’t or did not want to have soy, for example, then suddenly cutting out like one of the main proteins. So it’s like, it ends up getting more and more limiting depending on how many restrictions you have. The fussy eating thing as well. Like if somebody was a fussy, that makes it even harder. It’s just another thing that makes this more difficult too.

Leah:

And depending on the approach as well, this diet can be really, really low fat, particularly if it’s that whole, I’m kind of getting sick of saying this, whole food, plant -based, no oil, particularly if it’s that approach and the person is really excluding things like the nut seeds, all those more calorie dense things, your fat can be so, so minimal. Like the broad study, for example, they use seven to 15 % of calories coming from fat, which is quite low.

The bottom end of that low fat intake, is often linked with hormonal issues. So we’re like that seven to 10 % of calories coming from fat, like that is potentially a mark where we can start to get issues with hormone production, which again can lead to a whole host of issues.

Aidan:

And even on that, like the omega -3 kind of topic as well. The omega -3 is a big thing. Beause it’s like obviously no salmon cause it’s plant -based, but then even the other sources of omega -3s.

Leah:

Like chia seeds, hemp seeds, flax, like it’s cutting all those sources and then like, are you allowed to take an omega -3 supplement in like a microalgae supplement or is that still two calorie? It’s like, where do you find to refine? Like can you have something? It’s like, obviously many variations of this diet, but some of them are really restrictive.

Aidan:

Yeah. And from like a nutrient perspective, common challenges that you would often see on a plant -based diet in general, but often would be a little bit tougher on this diet. For example, protein, calcium, iron and zinc could be tougher. Because like if you’re thinking of like what are some great zinc sources, you’re starting to think like nuts and seeds, but they’re discouraged to a degree.

If you’re looking at protein, it’s like, okay, I can’t supplement protein because that is a processed food. You could once again then do tofu and stuff like that, but you’re now just like, you’re limiting your sources of protein a little bit as well. The list gets pretty long. Like even stuff like iron, it’s like, well, you can’t use any fortified cereals because that’s processed as well. You can’t use any fortified like mock meat or anything like that, makes it more difficult to.

Leah:

And there are some variations of this diet where they limit any processed foods, even things like tofu.

Aidan:

Yeah, I was wondering that. Like any kind of processing.

Leah:

So like there is a spectrum, but it definitely gets pretty insane, which makes all this micronutrient stuff way harder. So let’s have a little bit of a balanced summary. Obviously pros and cons, I think like the whole food plant -based, even the no oil part of that community, they don’t have the completely wrong idea.

The basic philosophy of focusing on high volume, low calorie foods for weight loss specifically is actually really helpful. We know that high volume, low energy dense foods that are high in fibre is gonna keep us full and be lower in calories and potentially kind of lead to that calorie deficit over time without focusing on restricting calories specifically. So from that perspective, it could be helpful.

But where I think it kind of flips over to be a negative thing is I think they take it way too far, especially in some variations of this specific diet. I don’t think demonizing foods solely based on their calorie density is helpful. Obviously, there are a lot of healthy foods that have higher energy densities like nuts and seeds, which yes, if your weight loss is your priority, you may want to limit, but also not everyone is aiming for weight loss. And there are a lot of people on this style of diet who don’t care for weight loss. It’s like, do you really need to exclude those particular foods at that point? Probably not.

There are also many, many minimally processed foods that are excellent sources of vitamins and minerals. So even things like your textured vegetable protein, fortified cereals, like you mentioned. Fortified plant milks is one that is like really often demonized for the small amounts of added oils that are in them. So by limiting these foods, it really makes it hard to meet your daily requirements for certain nutrients and it’s just unnecessarily restrictive.

So a simple summary is that it’s certainly not an approach I recommend. It’s not an approach I don’t recommend, but I think there are positive aspects of this approach, which we can take away from like the broad study for example, I think they’re onto something there. I just think the total restriction of this diet is unnecessary.

Aidan:

This has been episode 120. As always, we would appreciate a rating and review. So if you haven’t given us one already, we would massively appreciate it, preferably if it is five stars. Actually, probably only if it’s five stars is what we’d appreciate. But if you do that, we would absolutely love that. So thank you so much for listening.