Episode #363: September 2025 Research Review (Lifting and Fatigue, Injury Risk w/ Breastfeeding, Food Processing, and More!)

15:14Dr. Jordan Feigenbaum:Sure. OK, I see how you got there. Yeah. There are other things that we're going to ignore. So various metabolites, lactate, ammonia, PCR, ATP. These have been promoted as markers of fatigue. But this is even further up the stream from like how much force can your muscles produce, right? So like if you think about performance, like a one-rep max, and then you have to take a step back. Okay, max volitional isometric contractile potential. And then you have to take a further step back like metabolites. And you assume that these all have a, they're all related, but I'm here to tell you not as clean as you'd like it to be.

15:51Dr. Austin Baraki:Yeah, it's kind of a shotgun collection approach of all sorts of different intermediates that are just involved in like how muscles work. And so maybe doing these and seeing, is there some sort of a signal on the back end rather than going into this thinking or already knowing that any of them have utility from a, or validity from a fatigue measurement assessment predictive value type standpoint. But I agree, I wouldn't pay much attention to these basically like bioenergetic intermediates is how I would characterize a bunch of them. People love that.

16:19Dr. Jordan Feigenbaum:Yeah. All right. So let's talk about some results about the different types of training protocols and their effect on various measures of fatigue. So first up, training to failure versus not training to failure. So when people train to failure, regardless of the set structure, the loads or whatever, just generally speaking, when training to failure, you see more fatigue. So you see a greater reduction in maximum voluntary force production. You see a greater reduction in velocity during the set. You see a greater reduction in countermovement jump height so people can't jump as high after they do these things.

16:52Dr. Jordan Feigenbaum:And if you would predict if people – OK, look, 10 rep max, you can only do 10 reps by definition. Well, what if the person did forced reps afterwards? So they had spotters help them do another two or three reps. You would predict if training to failure produces more fatigue than not training to failure, then training past failure would produce even more fatigue. And, yep, you see that too, although there's only one study on forced reps in this whole systematic review.

17:16Dr. Austin Baraki:Yeah. Not groundbreaking findings here, I would say.

17:22Dr. Jordan Feigenbaum:Yeah. Okay. As far as the load is concerned, so the weight on the bar when training to failure, this is where it starts to get somewhat interesting because now you have multiple different variables in play. So generally speaking, when people train a failure with a heavier load, they're going to be doing less reps per set. It's just how this whole thing works. And then if it's a lighter weight and you train a failure, you're going to be doing more reps, so more volume. So more volume taken to failure generally produces more fatigue than less volume also taken to failure. So when you compare sets of 8 to 12 reps at an 8 to 12 rep max load versus sets of less than 8 reps also using whatever rep max load.

18:07Dr. Jordan Feigenbaum:So if you're doing a set of 5, it's a 5 rep max. You're doing a set of 6, it's a 6 rep max. Well, you see more fatigue in the sets with the higher rep range. So this is useful for somebody on the forum. Hey, would a set of 8 reps at RP10 be more or less fatiguing than a set of 5 reps at RP10? Well, you could say, the heavier weight of the set of five, maybe that's more fatiguing, but you did more reps with the set of eight. But now I can finally answer this kid's question, that based on these short-term acute measurements of fatigue, a set of eight at RP10 is going to be more fatiguing than a set of five at RP10.

18:42Dr. Jordan Feigenbaum:But as far as how that fatigue translates into your training load, well, that's a more complicated question.

18:48Dr. Austin Baraki:Yeah, I always find those types of questions interesting. thing it's just like i i i'm curious like why are you why why are you asking ahead of time like um just try it yeah yeah or don't yeah or don't sure you don't need to try to failure most of the time

19:04Dr. Jordan Feigenbaum:i mean to me it's they're asking a question to get it either something larger or to maybe inform like i said a larger decision uh but i would rather know what the decision point is that way i could actually provide a more useful answer sure like if you're asking me should i should i do fives are eights. I'm like, well, what are you trying to do? Because that would, I need that information.

19:24Dr. Austin Baraki:And the question and the answer to that might be that you might not need to go to failure in either scenario based on your goal.

19:31Dr. Jordan Feigenbaum:Yeah. Por que no los dos also. Yeah. Okay. So that's loads when training to failure. So you could interpret this and say, ooh, lighter loads are more fatiguing. It's like, well, because you're doing more reps, but I would not predict like seven reps versus six reps to have any appreciable difference. And again, to the extent that this measurement of fatigue actually matters when programming, well, that's a different story. As far as loads go when not training to failure, when matched for volume and effort, so total volume for a given workout and effort, so RP, for example. Heavier loads tend to be more fatiguing.

20:06Dr. Jordan Feigenbaum:Again, not groundbreaking research here. So 10 sets of five at 85%, 75%, or 50%, the heavier weight, so 85%, produced more fatigue with the same volume. Again, not shocking here. From a recovery standpoint, fatigue from lighter weights, lower volume, and further away from failure tends to be shorter lasting than heavier weights, higher volume, and going closer to failure. So five sets of 10 reps with a 10-rep max, the max volitional isometric contractile potential was reduced for one to two days. But if you did that same amount of volume, five sets of 10 with 40 percent of a 10-rep max, that reduction in max volitional force production lasted one to two hours.

20:56Dr. Jordan Feigenbaum:And so you're like, again, nothing really new here. Yeah, you do more volume, whether it's total or per set, we would predict more fatigue. It has to be different enough to matter, like one rep, different per set, probably not going to matter. We would also have told you before this that heavier loads tend to lead to more fatigue than lighter loads, generally speaking, especially when matched for volume and effort level. And the closer to failure you go, the more fatigue is going to be generated compared to staying further away from failure. The thing is none of these operate independently. So there's this optimization problem.

21:32Dr. Jordan Feigenbaum:It's like, all right, how many reps per set should I do? What is the proximity to failure? What load does that mean I have to use? I'm like, yeah, that's the art of programming. And I do not think that somebody can organize a training program well just based on short-term fatigue concerns. Does that make sense?

21:50Dr. Austin Baraki:Yeah, I think this lays out general principles that can be useful for somebody who is learning about this, things that can guide some basic decision making before you get to the individualization process when working with an individual person. I think that the more, I don't know how you feel, maybe more interesting conversation around differences in fatigue, because a lot of this can apply within the person. But if we get to the other aspect of the conversation of thinking not within individual, but between different lifters, how can we think about the differences in potential fatigue cost, for example, between a much, much stronger lifter, say, lifting a set of three to an eight RPE versus a not as strong lifter lifting a set of three to an eight RPE for them?

22:37Dr. Austin Baraki:and how does that impact maybe how we would go about decisions of programming them maybe in terms of training volume or frequency of exposure because there's certainly people who are exceptionally strong and you know they might expose themselves to certain lifts at certain intensities and volumes maybe a little bit less frequently whereas other lifters or even within a person other lifts they might be able to tolerate and expose them to much more often I think, for example, both you and I and some of our trainees have had periods of time where we've just like benched every day. I think that we've done that much more frequently than we have had anybody, ourselves included, like, you know, deadlift daily.

23:20Dr. Austin Baraki:I think that there are certain more psychological situations or pain and rehab oriented situations, but less often. That's not to say that you can't do that. There is there are people who can do that. But I think just as a general principle, you see that way less often. And so there is like the bro science-y kind of anecdote of people experiencing fatigue differently at much higher levels of absolute strength, even if the relative intensity or the RPE are similar. I feel like that's a perpetual conversation that we've probably gone back and forth on over the years and even to some extent experienced ourselves.

23:53Dr. Austin Baraki:Like I know that when I did just absolute one rep maxes when I was much less strong, you know, compared with my head, like the hardest lift that I've ever done in my life, I think, was when I pulled 765 sumo. And I was like, my performance was down for like three weeks after that. I was like, I feel real bad. And it was just an interesting thing to experience. So that was a lot of thoughts. I'm curious how you think about some of those things.

24:18Dr. Jordan Feigenbaum:Yeah, I mean, it's been interesting because I've been making this guided programming sort of algorithm. them. If we were going to be marketing geniuses, we'd just call it AI programming, but it's not. So anyway, when I think about things that likely influence fatigue, not using this definition, but fatigue, that's actually important for programming. I think load, absolute load is certainly an input. Heavier generally being more fatiguing than lighter. And I suspect that's even true as someone becomes more trained, which is interesting because as they become more trained, you'd expect them to be able to tolerate heavier loads.

24:55Dr. Jordan Feigenbaum:But they can also lift heavier loads and generate something more close to their absolute force production potential. I still think net, it's probably more stressful the heavier it is. I think about the proximity to failure, obviously going to failure and closer to failure. It's going to be more fatiguing than staying further away from failure, lower RPs. I think that compound exercises tend to be more fatiguing than isolation exercises, more muscle mass being used, bigger ranges of motion. And I also think freestanding exercise, free weight exercise, things with more balance or skill related components are more fatiguing than machine stuff.

25:32Dr. Jordan Feigenbaum:So like within this guided programming, I'm monitoring all of those things to come up with this training impulse score. Now, these are just made up numbers. And it'll remain to be seen if the cutoffs that I've been able to ascertain over my years of coaching, like translate well generally to people using this program, this thing on the app. But the cool thing about it is I'll have a bunch of numbers to look at. And we're not the only people doing this. There's at least one other person trying to do something like this. And we discuss this a lot as far as like, well, these are the relevant parameters.

26:06Dr. Jordan Feigenbaum:Here's what we're monitoring. And so it does get measured. And then you're trying to take that and say, how does this change our training approach for an individual? And so I'm hoping that clear things will emerge. But to be very straightforward, I don't know that any of this fatigue review stuff from this particular paper changes any of my opinions on this, right? It just gives me like a more reductionist answer to the kid, usually a kid unfortunately, who's asking me, hey, what's more fatiguing, a set of eight at RP10 or a set of 12 at RP10? And I'd be like, well, this set of 12 is a little more fatiguing but not in a way that you should care about.

26:51Dr. Austin Baraki:Sure. And also on average, you know.

26:54Dr. Jordan Feigenbaum:Yeah. Just don't care. So, OK, based on all this information, when trying to reduce fatigue, let's just say that somebody felt like I'm cooked. I'm overdone. I need to reduce fatigue. What do? Generally would advise that person to select rep schemes that are a little bit lower, likely lower than 12 to 15 reps, although most traditional resistance training programs would have lower rep schemes anyway. So this would really apply to people who are doing sets of 20 or more, a lot of blood flow restriction stuff, for example. because the volume per set is so high, it likely does incur more fatigue than the lower reps, even though it's using lighter weights.

27:35Dr. Jordan Feigenbaum:Each set should be taken a little further away from failure. So we've often advised folks to drop the RPE by one or two, stay a little bit further away from failure for a bit. And ultimately, we view that as a change that should reduce fatigue, but not necessarily reduce training stimulus, meaning the effect that it's going to have on somebody in most cases. We'd also advise making sure that rest periods are at least two to three minutes, especially for like isometric type stuff or machine-based stuff. And then for compound exercise, dynamic exercises that involve more of the body, particularly like squats, deadlifts, bench, stuff like that, probably longer, three to four minutes.

28:16Dr. Jordan Feigenbaum:It's as you reduce rest periods, you get sort of fatigue that carries over from set to set and it compounds and can be more difficult to dissipate. And as far as choosing a weight based on the rep scheme that you selected, your proximity to failure and the exercise, that's going to determine the weight. That's kind of how I view load selection rather than like prioritizing load selection first and then wrapping the reps and everything else around it. You could do it another way, but that's just kind of how I think about it.

28:45Dr. Austin Baraki:Yeah. These are some general guidelines for somebody who wants to do a quote unquote deload or a lower stress week or a lower even longer than a week potentially. And I think it reflects a lot of maybe how we've intuitively kind of gravitated a lot of our programming strategies in those periods. I tend to drop reps and pull RPE further from failure or put hard RPE caps or put absolute load caps on people. I might peel off a set if somebody's feeling particularly bad and then just give it time and ensure that the other pieces are in place, like making sure that they're sleeping enough. That's usually the first few steps to get people feeling better if they've dug themselves into a little too deep of a hole.

29:23Dr. Jordan Feigenbaum:Yeah. I don't want to just focus this entire podcast on a single paper or single topic, but I just want to get your take on this because this is one strategy that I have used for folks. It's a little reverse psychology is not the right word, but I think people understand what I'm saying. I'm trying to do the same thing I'd otherwise try to do, but just in a different way. So a five rep max is about 85%, somewhere around there. So 75 % should be, it's not a 10 rep max, but it's lighter. I can program people to do five sets of five at 75%. And then I see the set for whatever reason. And then the bar speed at the end is slow.

30:00And I'm like, it's too heavy for the day.

30:03Dr. Jordan Feigenbaum:Whatever the one rep maxes we're using is not good. But they're like, you said 75 % and you gave me a rep scheme. So it's a more concrete prescription. And even if I was like 75%, five sets of five, each set should be RP7. Just give them another sort of bumper there. They could still miss. So sometimes I'm like 75 % to RP7. No rep prescription. But it's like, look, load 75%, whatever you think that is. and you go until it's RP7, the person who's like very unsure of, you know, I'm not going to send it today, you know, the undershooter or whatever, they might be a little conservative, but they're still well within the constraints of like, this is going to work.

30:47Dr. Jordan Feigenbaum:And the person who overshoots often are more prone to that. Well, now we've given them like a barrier where they may be more conservative. I don't know. I kind of like that approach just to be like, I think if anything, you're going to undershoot just a little bit.

31:00Dr. Austin Baraki:Yeah, I think that that's a reasonable option for a strategy. As you get to know your athlete, as you get to know your lifter, who you're working with, you can kind of match the strategy towards their psychology and how they approach the bar. I mean, the chronic overshooter, who is, you know, is somebody who you need to approach much differently than the chronic undershooter. They both also, in addition to different programming strategies need like, you know, conversation around this very issue over time. And then you bake it together maybe with some programming strategies that show them maybe how to do it in more the way that you're trying to prescribe.

31:36There are also people who, you know, the much

31:40Dr. Austin Baraki:more powerful lifters who tend to move the bar really, really, really fast or not at all. And then the people who even their first rep looks like a grinder, but then they proceed to hit another four or five more and that's just stuff you need to get to know about the person to get a sense i've had definitely lifters of both varieties and need to you know not only think about them differently maybe some degree of differences in programming but also it's like when i'm watching your videos like um i i come to very different conclusions based on the based on the person um which is interesting sometimes yeah yeah just the yeah people there are people

32:14Dr. Jordan Feigenbaum:from all at all all different ends of the spectrum uh last thing here there's this odd notion that's been going around and maybe this is probably really why i chose this paper i buried the lead it's like lower rep sets are better than higher rep sets because of reduced fatigue and and i'm not really talking about in respect to like maximal strength development because that's certainly true not because of fatigue though just because of the said principle like sure if you're trying to get an improvement one rep max and you're doing sets of 10 you're missing the boat here so we need some lower rep sets but the people say this for hypertrophy they're like oh you have to do sets It's a six or eight because you go above that.

32:49Dr. Jordan Feigenbaum:More fatigue. More fatigue because of more reps. Come on. You just said that in this review paper. So what? If it were true that training with higher reps caused more fatigue such that a person's training tolerance was compromised, meaning they couldn't do it as much volume, right? Or they were overcooked and effectively they were giving all of their recovery resources towards just keeping up with the training and not being able to generate any muscular hypertrophy. You would see that in the research. You would see that reliably sets of six reps, seven reps, eight reps, nine reps, whatever would do better than sets of 12 reps, 15 reps, 20 reps.

33:30Dr. Jordan Feigenbaum:But you don't. And it's not like there's one paper on this, two papers. There's dozens of papers on this. And like criticisms of exercise science aside, if your hypothesis is X and there's no support of X, you got to call it a hypothesis until papers showing the opposite come out and then you're like, I need to revise my hypothesis.

33:50Dr. Austin Baraki:Yeah. Or especially if your hypothesis has been directly tested and did not pan out the way that you thought. Yes.

33:56Dr. Jordan Feigenbaum:People are like, yeah, so I should only do sets of eight on like biceps curls and lateral raises. I'm like, well, you can. But the idea that that's better than sets of 10, I'm like, look, I got a bridge to sell you then. Yeah, right. All right. I'm done. We spent 30 minutes on it. I'm so sorry. Look, if you— You did this. I did this. And I'm fatigued, honestly. Like, I might have to reduce my training today because I'm so fatigued.

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40:41All right.

40:42Dr. Jordan Feigenbaum:So we're back here on the Barbell Medicine Research Review from September 2025 with Dr. Austin Baraki. Austin, we're about to talk about boobs. You ready?

40:51Dr. Austin Baraki:Okay.

40:52Dr. Jordan Feigenbaum:Solid transition. Yeah. Breastfeeding injury link. Our concerns warranted. That's the name of the paper. It's by Jones et al. An international group of researchers, mostly out of Canada. Shout out to Canada because their pregnancy exercise guidelines, I thought were pretty good and they keep putting out research in the space. So 10 out of 10, we'd recommend checking those out. They're linked in the description below. This was published in the British Journal of Sports Medicine, August 2025. Brief aside, I don't want to bother you. It's my general rule of thumb. Don't bother, Baraki. I paid$65 for this article.

41:22Dr. Austin Baraki:Well, you also did that yourself as well. I could have probably pulled it for you with my institutional access.

41:27Dr. Jordan Feigenbaum:That's true, but I wanted to complain about it publicly.

41:29Dr. Austin Baraki:Oh, okay. Well, carry on then. If we agree that women in the peripartum section are a very important population, that they're generally underserved with respect to research and exercise science, and it would be beneficial to promote exercise and safety of exercise

41:46Dr. Jordan Feigenbaum:during this, then why is this paywalled? Yeah.

41:50Dr. Austin Baraki:Well, because journals don't care about that. That's true. Yeah. Elsevier is not concerned with any of that.

41:57Dr. Jordan Feigenbaum:No, Asana is not concerned. Yeah, it's like everyone complains about big pharma and big, you know, well, whatever. How about big journal?

42:06Dr. Austin Baraki:Yeah, underrated villain.

42:08Dr. Jordan Feigenbaum:Underrated villain. Yeah. All right. Maybe for another podcast. All right. So a little background here. Exercise and pregnancy is generally good. No surprise there. However, it is underutilized and underprescribed. So the current epidemiology with respect to how many women who are pregnant actually do exercise, Those statistics are pretty similar to the GenPOP. So if you ask people, about half of folks will say that they're exercising where only a quarter are actually following the current guidelines. But that's for aerobic training only and then you combine resistance training and there gets much, much less.

42:41Dr. Jordan Feigenbaum:Interestingly, when you look at data on healthcare professionals and how often they actually counsel their pregnant patients on exercise compared to their non-pregnant patients, they do it less. which they have, there's so many, so much more healthcare interaction interfacing. Like you see so many more healthcare professionals, you would think if anything, it'd be higher just based on numbers, but it's like, are healthcare professionals scared? Do you think like, what's the deal here?

43:06Dr. Austin Baraki:Yeah, it's a complicated. And I know that we're going to be bringing the other Dr. Baraki on the podcast soon to talk about some things. And we can probably revisit this and get her thoughts as somebody who has experienced not only doing this work and providing physical activity counseling, She's one of the good ones in this arm of things. But it is not a fundamentally incorporated element in their clinical training. And so I think that there are a lot of things where when there is not that explicit incorporation into training and repeated training on a particular topic, then it either doesn't get addressed at all or people's uh prior layperson views as a physician like whatever you might have otherwise assumed as a layperson regardless of your medical training it almost just ends up filtering through into your professional identity yeah so so to give a more because that was a maybe a little bit of a nebulous description but we've talked about this with like back pain for example you know a lot of clinicians doctors included are not great at counseling patients around back pain and they tend to spout off a lot of nonsense uh that can't be good for you or this that the other thing whatever which are not based on good evidence or you know best practices for managing back pain but rather are just like their doctors are also just people and so whatever beliefs they already had about backs just carry through except now they are being presented with the professional authority of the title uh along with it right so i think when it comes to exercise prescription, there's a few things.

44:42Dr. Austin Baraki:There's the fact that there is limited to no explicit, repeated incorporation of it in their training. There is the element of it kind of getting coming through their layperson beliefs coming through. And then there's also lastly would be the aspect of who sees all the bad things that happen. Yeah, fair. That's what would be the obstetricians, all the complications, the miscarriages, the hemorrhages, things like that. And so I've talked about this recently elsewhere, too, when we talked about the New York Times back pain kind of thing and several others where there is also your own selection bias as a clinician of not necessarily seeing all the people who are doing fantastically well with things but seeing more of the bad things.

45:22Dr. Austin Baraki:And so then that also informs your layperson views, which still come through. So I have a lot of thoughts on this, obviously, but that's kind of my best cohesive explanation for why this kind of statistic emerges.

45:31Dr. Jordan Feigenbaum:Yeah, it was just interesting to me that, again, you would think if you're seeing healthcare professionals more, you're going to potentially run into somebody who's pro-exercise more frequently. But apparently that's not in proportion to just this avoidance of discussing exercise and exercise counseling. And oh, by the way, if you happen to be a pregnant woman with obesity, well, your rates of exercise counseling are even lower, which – Backwards, yeah.

45:57Dr. Austin Baraki:I mean, I guess.

45:59Dr. Jordan Feigenbaum:Yeah. But again, I think it's complicated. To your point, there's a lot of stuff here. So yeah, it's good for mom. We know that regular exercise, regardless of if you're pregnant or not, it improves strength, muscle mass, physical functioning. In pregnant women in particular, it does tend to decrease the amount of weight gain, which for most in modern society, that tends to be better, but not all. Reduces the rate of complications. We talk about gestational diabetes. That's getting diabetes while the person is pregnant, gestational hypertension, preeclampsia, improved mood, reduced risk of depression, lower incidence of cesarean delivery, et cetera, et cetera, et cetera.

46:36Dr. Jordan Feigenbaum:It's also good for baby. Pretty much every measure of like health for the newborn infant tends to improve, higher IQ, lower incidence of low birth weight, heart condition, risk reduction, all sorts of stuff. There's this mechanism that I thought was super interesting, that physical activity and the vibrations related to it improve fetal brain development. That's a mechanism that's been thrown out there. But anyway.

46:57Dr. Austin Baraki:Yeah, there's a big mix of things that are associative, correlative data there and some that are more likely to be causative. And we can leave that for another conversation. Yeah. 100%.

47:06Dr. Jordan Feigenbaum:But unfortunately, despite all these known benefits, physical activity levels are generally lower during and immediately after pregnancy. So there's that. That's like that's baseline. And there's been additional concerns over increased risk of musculoskeletal injury during breastfeeding after delivery, mostly due to low energy availability-related concerns. So like we've talked about REDS, relative energy deficiency in sport. So this is a concern maybe with somebody who's previously a competitive athlete and then they want to return rapidly to their pre-pregnancy weight. This has not been shown in any data set, but there's like this theoretical concern.

47:44Dr. Jordan Feigenbaum:There's also this theoretical concern that the change in the physiological milieu – shout out to Walter Cannon and Claude Bernard – that the hormone situation post-delivery, postpartum, may favor bone resorption. And so there could be a bony injury, an increased risk there. That's been shown – not shown but said in the literature a number of times. Although, again, when you look for data on this, it just isn't really there. So these concerns are present in like professional societies. and then you also have less physical activity happening in the gen pop. So the purpose of this study was like, let's just see.

48:21Dr. Jordan Feigenbaum:What is the musculoskeletal injury risk in the postpartum period? Is breastfeeding a unique risk factor? So this study recruited 590 individuals who had delivered a child in the last two years. The average age was 33 at the time of delivery. They were all greater than one year postpartum and they have exercised during that time. All of the data is captured here via questionnaires. So they got demographic data. They got reproductive history data, breastfeeding practices, physical activity levels, injury and pain. Now questionnaires – we could do a whole separate podcast on how questionnaires can be torn apart.

48:59Dr. Jordan Feigenbaum:But like it's a convenient sample I assume. Yeah. Just like a –

49:03Dr. Austin Baraki:Almost like a pragmatic observational study. Yep.

49:06Dr. Jordan Feigenbaum:So they defined injury in this study on a questionnaire based as tissue damage or other derangement of normal physical function due to participation in sports. I tried to find the actual questionnaire just to see like what question because like if that was a question on a survey, I'm like, are tissue damage derangement? I don't know if that has – is super well understood. But they asked about injury. They asked then if someone did have an injury, the location, the type, and the treatment. And this was reviewed by one of the authors who's an exercise physiologist. So some level of quality control with respect to injury.

49:41Dr. Jordan Feigenbaum:And then pain was defined as unpleasant sensory and emotional experience associated with or resembling actual or potential tissue damage.

49:51Dr. Austin Baraki:Yeah, that's the traditional IASP definition of pain. So that's fine. And they said that pain alone was not indicative of a musculoskeletal injury, which I saw that. I was like, go and redeem yourself, right?

50:04Dr. Jordan Feigenbaum:Right. Okay. So that's the study design. As far as the results, one in five women reported a musculoskeletal injury postpartum. 60 % of those who were injured were exclusively breastfeeding. That was the same rate for those who were not injured and were also active. Most common location was in the lower limb. And that was true before pregnancy and also after pregnancy, although the percentages changed. So before pregnancy, when people reported an injury, about 65 % of the time, two-thirds of the time, it was in the lower extremity, so the thigh, the knee, the ankle, the foot. And that was about 40 % after delivery.

50:44Dr. Jordan Feigenbaum:About 20 % of injuries before delivery were in the groin, hip, pelvis, low back. That jumped up to about 26 % after delivery. And then prior to pregnancy, pre-pregnancy, it was 10 percent happened in the upper limb, whereas 20 percent after delivery. So some changes there, but that's the injury location story. This was really interesting, the amount of exercise that these people were doing. So one of the big risk factors for having an injury after delivery was a decrease in exercise volume. So a drop in 50 percent or more in exercise volume during the first or second trimester nearly doubled the risk of injury.

51:26Dr. Jordan Feigenbaum:It's 89 % increase in injury risk. Now, to be clear, this selection, this sample was very, very active. They were doing 2 ,100 met minutes per week of exercise. Self-report, so like whatever. But just to put that in perspective, the current physical activity guidelines recommends 500 to 1 ,000 met minutes per week of conditioning efforts. These people were doubling that. You know?

51:53Dr. Austin Baraki:Big if true.

51:54Dr. Jordan Feigenbaum:Big if true. Yeah. So I think just the people that they recruited or the way that exercise volume was ascertained maybe inflated that number. But generally speaking, people exercised much less postpartum than before pregnancy. And if they dropped exercise volume by more than 50%, that seemed to be a significant risk factor for developing a musculoskeletal injury after delivery. No surprise there. We can hem and haw about mechanisms here when we discuss the take-home message. The other big risk factor here was disordered eating. Disordered eating increased risk nearly tripled the risk of injury after delivery.

52:34Dr. Jordan Feigenbaum:So 276 percent increased risk. That's the headline. No surprise that disordered eating because we know that low energy availability and reds when present even outside of this population does tend to increase risk of injury. Perhaps the second most interesting thing, to me, the most interesting thing being how much exercise these people were doing allegedly. Sleep didn't really play a role here. That sleep quality did not seem to be a significant risk factor for developing an injury, although it was good in both the injured and uninjured. Good for them. So I think both individuals or both groups were sleeping pretty well.

53:11Dr. Jordan Feigenbaum:So maybe that's the key here. So my take home for this, I'll get your thoughts on this. breastfeeding in the postpartum period is not a significant risk factor for injury in women, whereas low energy availability, REDS, and nutritional concerns probably are a significant risk factor for developing musculoskeletal injury, a new musculoskeletal injury. And so it may be useful to use if you're in practice, if you're a dietician, if you're a healthcare professional and you have concerns about this or just want to monitor it, there is questionnaire. It's called the LEAF questionnaire, low energy availability in females.

53:47Dr. Jordan Feigenbaum:I've linked that in the show notes below. So if you just want to kind of check the box to make sure it makes you feel better about recommending exercise to your postpartum women, there you go. My other take home from this is that more women need to exercise and need to maintain that exercise throughout pregnancy to the best of their ability and in the postpartum state. I do think that it is a complicated time. There are a lot of demands that are new, time restrictions, feeling comfortable going to the gym, for example, maybe doing the same exercises, using the same equipment or whatever, especially as the body has changed.

54:24Dr. Jordan Feigenbaum:But I do see this fall off in physical activity during pregnancy and then afterwards, potentially for both mom and dad, being problematic, not only from an injury risk standpoint, but also just like long-term health trajectory, health of the child, things of that nature. So I don't know. What do you think about all this?

54:44Dr. Austin Baraki:Yeah, my thoughts, it's interesting. It does seem like a pretty highly selected sample, as you mentioned, if they really were that active. And so there's always going to be questions about how generalizable is this to the average kind of member of the population going through this. But that's one interesting observation. The other couple things I thought of was one risk factor you mentioned was a drop of 50 % or more in exercise volume during the first or second trimester, nearly doubling the risk of injury. That's an interesting kind of correlate. The challenge there is, as usual with these types of papers, is that drop directly leading to the subsequent risk of injury, which does have some plausibility, right?

55:28Dr. Austin Baraki:So say you are somebody who is very habitually physically active, and then you drop your volume 50 % or more, and then you get after delivery, and you feel like maybe you're in the clear and you want to get back to what you were doing before and you ramp it up too much too soon? Sure, that's one plausible way. Or is it that something else came up during their pregnancy, either health-wise, musculoskeletal-wise, whatever the case is, that caused them to drop that exercise volume during their pregnancy? So the causation goes in a little bit of a different direction. And then the last thought is related to the disordered eating.

56:01Dr. Austin Baraki:So totally agree, disordered eating, well-known to associate, especially when that disordered eating is the low energy availability variety, increasing risk of things like stress fractures and various other types of things. But also we know that disordered eating correlates in other ways with negative health outcomes, including mental health outcomes. And then that also correlates with pain issues, pain intensity, disability from pain, things like that. So there's a lot of just complex interacting variables going on here. And so I don't envision that we'll ever see, for example, a trial that randomizes pregnant women to drop their volume by 50 % or not, and then see how injured they get afterwards.

56:41Dr. Austin Baraki:That's like a preposterous kind of study to even propose here. But maybe rather than more of a cross-sectional design, as it seems that this was more of an ongoing prospective cohort type design might be another interesting design to look at this kind of thing. So I agree with that aspect and several of your other thoughts that, you know, my hope is that we can continue to not only destigmatize this or allay some of those common fears and concerns, but folks who are actually practicing in this space, leading in this space, like my spouse, who we'll talk to again soon about this, can train their current crop of residents that she is now educating every day to, you know, better counsel their patients, not only to do it, but to do it accurately, as I have already started to observe her doing at our new institution, you know, giving explicit feedback to her trainees on, did you counsel them on physical activity?

57:37Dr. Austin Baraki:What did you say? And then correcting a lot of things that might have been inaccurate, just because, again, a lot of people bring in their just lay beliefs in with an MD behind their name, and that can be problematic.

57:46Dr. Jordan Feigenbaum:Yeah. Yeah. You would want clinicians to not only broach the topic, period, like bring it up.

57:52Dr. Austin Baraki:Yeah.

57:53Dr. Jordan Feigenbaum:You'd want them to do it in a way that is accurate. So look, there are no free biological lunches, but we think on balance, the benefits far outweigh the risks here. And for you in particular, like here's what we're thinking. And then also be able to do some effective behavior change counseling. So whatever sort of obstacles or barriers that somebody may have, be able to allay those in some fashion.

58:20Dr. Austin Baraki:Which also requires the physician themselves to be somebody who exercises to be able to speak on this. It makes it a lot easier to counsel people on options for it, modifications, working through barriers if you have been through that. If you have no concept of this, how are you going to do that? And so that's another gap that needs to be shored up. If you allow me to put my RFK junior hat on for a second,

58:43Dr. Jordan Feigenbaum:Oh, okay. Here we go. So just speaking about that, it would be a solution that is indirectly related to something but sounds good. I actually think this would be maybe more effective, but we'd have to see. Exercise training in medical school. You could have an entire class, longitudinal class, that's about the exercise guidelines, behavior change counseling, et cetera. That would be one arm of my study here or like – and the other arm would be like, no, it's just PE class. But PE class is actually like you need to exercise and we're going to teach you how to do it. I suspect that the people actually doing it would be not only more enthusiastic about making their recommendations but also be able to discuss this a little bit more passionately and personally with their patients if they were actually exposed compared to just reading about it.

59:35Dr. Jordan Feigenbaum:I don't know. What do you think about that? that's a plausible hypothesis yeah

59:39Dr. Austin Baraki:to be tested

59:40Dr. Jordan Feigenbaum:I'll call RFK up we'll all right last last point on this I actually do think there needs to be more research on this population so like most study designs particularly an exercise sign ah they can't be pregnant or they can't be like recently pregnant and it's like why yeah totally it'd be interesting just a subgroup analysis just to have something some data on there

1:00:12Dr. Jordan Feigenbaum:Last study here on our September 2025 research review. This paper is called Ultra-Processed or Minimally Processed Diets Following Healthy Dietary Guidelines on Weight and Cardiometabolic Health, a Randomized Crossover Trial. This is by Dickin and a research group mostly out of London. It's published in Nature, August 2025. So, okay, a little background here. Obesity obviously is an epidemic. We know that obesity rates have tripled over the last 50 years. We think this is mostly related to the environment, not only the food environment, where there are highly palatable, highly desirable, high-calorie foods that are not that satiating literally everywhere.

1:00:55Dr. Jordan Feigenbaum:And by the way, they're cheap. Those are everywhere. So that's the food environment. And the physical activity environment has also changed. There's less occupational activity. There's less recreational activity. In general, these two things combine to produce a very predictable outcome with our very stable genetics that have not been sort of adapted to our modern environment. So that's the story. That's the background here. With respect to food processing, there's this notion that ultra-processed foods are generally more deleterious, more harmful to health trajectory, specifically through weight trajectory.

1:01:33Dr. Jordan Feigenbaum:So how people gain weight over their lifetime, body composition, and related sort of parameters of health, so blood pressure, blood sugar, et cetera, et cetera. The most commonly used food classification system relative to processing is called the NOVA food classification system. This was published in 2019. This is just a name. It's not an acronym. It doesn't stand for anything. And it is funny in the research. You'll see it capitalized in some papers, just NOVA, all capitalized. and other times it's not – the N is capitalized. I'm like –

1:02:04Dr. Austin Baraki:Do they know that it's a name and not an acronym? I don't know.

1:02:08Dr. Jordan Feigenbaum:Yeah, do they know? So when it comes to minimally processed foods, this is also known as NOVA Food Classification System Group 1. These are unprocessed or minimally processed foods, fruit, vegetables, eggs, meat, milk, water, etc., things like that. And then ultra-processed foods are Group 4. These are ones that use many ingredients like food additives, ingredients rarely used in home food preparation. food ingredients that are mostly pertinent to industrialized processing techniques to improve palatability, preservation. So this includes stuff like sweetened cereals, pastries, pre-prepared meat, pasta, pizza dishes, chips, et cetera.

1:02:45Dr. Jordan Feigenbaum:Also things like whey, also things like Greek yogurt, some variations thereof. So not all ultra-processed food is the same. Perhaps the most common ingredients that we would be on the lookout here would be added salt, added sugar, and added fats. These are common ingredients in ultra-processed foods, generally increasing the palatability, the mouthfeel, the desirability of these foods. We'll come back to that. So that's minimally processed versus ultra-processed based on the NOVA food classification system. Now, the thought here is that if we were to transition most people's dietary patterns, most eating patterns to a minimally processed or unprocessed – to consist mostly of minimally processed or unprocessed foods, well, then they would eat less calories.

1:03:27Dr. Jordan Feigenbaum:because the thought here is that minimally processed foods are more satiating, more filling, that the macronutrient intake would be more similar to the current dietary guidelines. The micronutrient status would also be more similar to the current RDA. And so all of these things combine to just have people eat less food and be healthier. Now, two previous studies on this have been done directly comparing ultra-processed foods versus minimally processed foods. They were both done in a metabolic ward. Basically, they're keeping humans under lock and key like lab rats. The first one was by Dr. Kevin Hall in 2021.

1:04:03Dr. Jordan Feigenbaum:It was a two-week-long study where people first ate either – they ate one of the two diets and they flipped over to the other one. They either ate ultra-processed food diet or a minimally processed food diet. They could eat as much as they wanted and then it just looked at like what happened over two weeks. On average, people ate 500 more calories when they were exposed to the ultra-processed food diet. And within the two weeks on that particular diet, the average weight gain was like one kilo. The second study on this was done in 2024. Same thing, metabolic ward study where people could eat as much as they wanted, either an ultra processed food diet or a minimally processed food diet, depending on which arm they were randomized to.

1:04:40Dr. Jordan Feigenbaum:On average, they ate 800 calories more per day on the ultra processed food diet, leading to a 1.1 kilo weight gain within one week of exposure to this particular dietary pattern. So all of this is suggesting like there's something unique about these ultra-processed food diets that are leading to weight gain. So this study set out to compare ultra-processed food diets compared to minimally processed food diets over a longer period of time, eight weeks in this case, to see what the differences are in weight, body composition, appetite, and more. So this study took 43 adults. The average age was 43, mostly women with the average BMI of 32, but these were weight-stable individuals.

1:05:19Dr. Jordan Feigenbaum:None of them had type 2 diabetes. None of them used insulin, no eating disorders, no inflammatory bowel disease, no dietary restrictions. And at baseline, the average habitual ultra-processed food intake for the group was 70 % of their daily calories. Wow. That is high. A little bit higher than in the States where we're about 50 % to 60%. Yeah. Obviously, that varies depending on the individual because I don't eat hardly any. Yeah.

1:05:43Dr. Austin Baraki:Yeah.

1:05:44Dr. Jordan Feigenbaum:Same. But yeah, so I thought that was relatively interesting to see what they were at baseline, but we're going to come back to that because I think that is important. All the food was provided for these individuals for eight weeks. I assumed every week they went and picked up all of their food, and they were provided with up to 4 ,000 calories a day of food. And they were instructed to consume as much or as little of the provided diets as they wanted to. And so they were randomized to either start with the ultra-processed food diet or minimally processed food diet, follow it for eight weeks. Then they had four weeks of doing their own thing, and then they switched to the other arm.

1:06:15Dr. Jordan Feigenbaum:The outcomes that they were looking at were weight gain, weight trajectory, body composition, body composition, which was analyzed by bioelectrical impedance, BMI, blood pressure, A1C, liver-associated enzymes, a lipid panel, various surveys for cravings. So there's a power of food scale and a control of eating questionnaire to kind of try to figure out, like, do people have these cravings, desires for specific foods, and appetite. questionnaires. As far as the results go, well, the adherence to both diets was pretty good, about 90 % both the times, which is pretty good. The energy intake on average was 327 calories less per day with the minimally processed food diet compared to the ultra processed food diet.

1:07:03Dr. Jordan Feigenbaum:As far as weight change goes, the minimally processed food diet, that arm in eight weeks, lost about two and a half kilos on average, whereas the ultra processed food arm, they lost about 1.5 kilos on average. Now, this is 2.7 % of starting body weight loss for the minimally processed food diet and 1.7 % body weight loss for the ultra processed food diet. This is not clinically significant weight loss, just to point that out. So we'll probably come back to this, but just that take home is like, look, just switching somebody over to a minimally processed food diet may not, and in fact, in this case, does not seem to produce minimally clinically significant weight loss, at least within eight weeks.

1:07:43Dr. Austin Baraki:Yes, the time for is important here. For sure.

1:07:45Dr. Jordan Feigenbaum:For sure. It's not quick in that case. As far as body composition goes, the minimally processed food diet, they lost about two kilos of fat mass and the ultra processed food diet lost about one kilo of fat mass. BMI was – they went down in both groups about one point in the minimally processed food diet, about half a point in the ultra-processed food diet, owing it mostly to the amount of weight loss. As far as blood pressure goes, this is like the only significant change of like a health metric. It went down about double in the minimally processed food diet compared to the ultra-processed food diet.

1:08:23Dr. Jordan Feigenbaum:So 4.7 millimeters of mercury on average reduction for systolic blood pressure. That's the top number. and 3.3 millimeters of mercury diastolic blood pressure. That's the bottom number for the minimally processed food diet, whereas about half as much for the ultra-processed food diet. And it was significant only in the minimally processed food diet. Pretty decent changes, especially with the modest weight loss. But other aspects of health, other measures of health, like the A1C, the liver-associated enzymes, the lipids, were not significantly different between the two groups. And the appetite and satiety ratings were also not that different, which is not something you would predict, but ultimately not terribly surprising with this modest amount of weight loss.

1:09:03Dr. Jordan Feigenbaum:Sure. Yeah.

1:09:04Dr. Austin Baraki:Yeah, I think it's an important hypothesis to look into, especially with the current discourse, you know, in recent, in the past year to a couple years, shifting harder and harder in this direction of ultra processed foods being like the number one public health villain out there. And, you know, we're not necessarily proponents of everybody should be cranking up their intake of these foods. but I think that accuracy matters when it comes to our claims. And also what the implications would be from a management standpoint, as we keep coming back to like, okay, so what are we going to do with the information that we have?

1:09:38Dr. Austin Baraki:And does it make sense to put all of our clinical effort, for example, when working with somebody with obesity, just hammering them over and over and over again, nonstop about their use of ultra processed foods. Is that justified based on the evidence of benefit or harm from, you know, different, these different dietary approaches. You know, I think that you and I both agree when we're working with somebody or talking about this topic that these types of food items do come up and they tend to come up pretty early in the conversation as potential targets for intervention. but it is part of the broader conversation, part of the broader intervention, which includes other dietary aspects, which includes options for kind of intensifying our intervention to include things like medications or surgery.

1:10:21Dr. Austin Baraki:If we're trying to really help the person reduce their risk of morbidity, disease, and death, then we are kind of open to any tool with good supporting evidence behind it. And rather than saying, it's just gotta be the food and excluding other potentially beneficial interventions, which is actually what some people are suggesting. Yeah.

1:10:42Dr. Jordan Feigenbaum:Yeah. I mean, I think the most fair shake on this particular study is that when there is similar food availability in the environment, a food environment that consists predominantly of minimally processed foods, it's going to produce a better weight trajectory than one that is rife with ultra-processed foods, which is not groundbreaking. The problem is our modern food environment is not that way. And so one of, to your point, one of the early things I work on from like a food related standpoint with people is trying to modify their micro food environments to the extent that's within their control.

1:11:17Dr. Jordan Feigenbaum:So that's stuff at home, in the office, et cetera. Obviously their commute to work is something they cannot control. Their immediate environment outside of their home. So like restaurants that are around where they live, grocery store access, et cetera, not really within their control and so kind of fighting this uphill battle in many cases. So with respect to that, if that's our baseline understanding that when given similar food availability in the environment, minimally processed foods tend to produce better health trajectories than ultra-processed foods, why is that? And there's really three kind of layers to this.

1:11:54Dr. Jordan Feigenbaum:One is from a nutrient perspective. So on average, ultra-processed foods have a higher energy or calorie density per unit mass than minimally processed foods. There's about double the amount of calories per gram, for example, in ultra-processed foods. Oh, and by the way, they have lower nutrient density, whether it's vitamins and other sort of minerals and such. Ultra-processed foods also tend to be higher in saturated fat, added sugar, added sodium. These are ingredients that when used in particular combinations that food scientists are very, very aware of. They are very potent stimulators of appetite.

1:12:27Dr. Jordan Feigenbaum:So people tend to overeat and they're not very filling, satiating. So people tend to eat more calories. And also when people eat these foods, they tend to displace or otherwise take the place of foods that would be higher in fiber, higher in protein, higher in other micronutrients. And so generally speaking, when we look at people including a particular type of food, we're like, well, what does this replace or displace, for example. And in this case, when you replace foods that are high in fiber, foods that are high in dietary protein, low in fat, whatever, with ultra-processed food, people tend to eat more calories.

1:12:59Dr. Jordan Feigenbaum:How many more calories? Well, in the short studies, the one-week, two-week-long metabolic ward studies, it looked like 500, 800 calories in that short term. And in this particular study, it was 400 calories. And so it's going to balance out a little bit over time. It's not going to be this piece people reading on average 800 calories more per day for a year. Well, and it's going to, you know, people just don't gain weight in perpetuity like that. So it's going to balance out. But yeah, people tend to eat more calories. So that's like one layer of this onion. The second layer goes back to this food environment.

1:13:30Dr. Jordan Feigenbaum:Again, ultra processed foods are everywhere. And not just that they're everywhere, but they're cheap. They are desirable based on marketing and taste. And oh, by the way, they have large portions, generally speaking, high in calories. People have discussed this concept of food deserts when it comes to the food environment where there's just a lack of access to healthy food. So you don't have a lot of grocery stores with fresh fruits, for example. You have a lot of fast food establishments in your local environments. These are called food deserts. And so the thought was, well, you just build a salad store somewhere in there.

1:14:07Dr. Austin Baraki:And people will just flock to it.

1:14:10Dr. Jordan Feigenbaum:That transitions to another term called food swamps. And it's like, look, you have some access, but it is overwhelmingly outpaced and outmatched by these sort of less healthy options. And so you can't just build a salad store in one of these food deserts and hope that people are going to eat that more often. And so, yeah, the food environment tends to be mostly oversaturated with these ultra-processed foods. And it tends to be disproportionate – disproportionately kind of seen with respect to socioeconomic status. The lower socioeconomic status locations tend to have more of the ultra-processed foods than higher socioeconomic status sort of locations.

1:14:53Dr. Jordan Feigenbaum:And so it's disproportionate in that aspect. And then the last component here with respect to ultra-processed foods has to do with this cultural and society-wide tendency of eating more foods that are prepared outside of the home. So most recent data on here shows that American adults eat about 3.9 meals that have been prepared outside of the home per week and 1.8 meals from a fast food restaurant per week. Wow. And yeah, there's subgroup analysis on this, particularly in those with obesity and overweight, tends to be even worse in those populations. Food prepared outside of the home tends to be much less health-promoting for reasons that you can probably guess.

1:15:35Dr. Jordan Feigenbaum:They're higher in fat, higher in calories, less satiating, lower amounts of micronutrients, lower in protein, all sorts of stuff like that. And yeah, when you look at data on is there a dose-dependent relationship between how many meals are eaten outside the home and BMI and body fat and weight trajectory? Yes, all of those things exist. The more meals that people consume that are prepared outside of the home, the higher their BMI gets on average, the higher their weight gets on average, and the higher their body fat gets on average. Now whether this is like a cultural trend to eat more foods outside of the home, breaking bread with friends for example, whether it's a food environment-driven change like, oh, we just have more access now.

1:16:14Dr. Jordan Feigenbaum:I can't speak to that. That's a whole other podcast topic, but generally speaking, more foods that are eaten, that are prepared outside of the home tend to be worse for health. Not particularly surprising, but it's like you have these three things. The more ultra-processed foods and the environment. Food environment, generally speaking, it makes it harder to eat very healthy foods. And oh, by the way, more people are eating outside the home on top of that. It's like the three horsemen of the apocalypse here.

1:16:41Dr. Austin Baraki:That's how we ended up here, among still other reasons and why it's such a difficult one to fix and why I think that solutions or proposed solutions that sound straightforward and simple are unlikely to be quite as effective as we would like. And so, you know, I have listened to a lot of folks talking about this, and I've certainly tried to listen and understand the mentality that the current kind of crop of folks in our administration are taking and their thought process. And just like, you know, we are where we are right now, and these are the folks who are kind of guiding policy and trying to understand how they think about things and observing this thought process of what they call like what they describe as incrementalism.

1:17:25Dr. Austin Baraki:For example, there's the aspect, for example, around like, let's ban food dyes. And a lot of dieticians and other folks who have expertise in the nutrition space are like, well, banning food dyes is not going to meaningfully move the needle with respect to population health, which is a position that overall, I think you and I are inclined to mostly agree with. you could envision second order third order like downstream effects where it's like if this is removed and the food looks less appealing and then a child for example is less likely to eat it and then assuming they substitute it with something that is more health promoting and then that is persistent over time and the food industry doesn't like counter-engineer other other things then at the end of that you know like potential causal chain maybe health outcomes are improved um and And so it's like that feels like a much more kind of, I don't know, convoluted way to get to the outcome that you want compared with more directly and aggressively targeting the bigger levers that we are more confident have a bigger impact on this outcome.

1:18:30Dr. Austin Baraki:And so it's, yeah, it's just a complicated time to be involved in the space that I think everyone on all sides of this issue are interested in healthier populations. I think the routes that we would take to get there, the variables that we would aim to manipulate are likely to be pretty different. And so I think that this study is one among a growing body of research that helps us to recognize that, yeah, there's probably some benefit. We will continue to recommend reducing people's habitual intake of these foods. But I don't think that this is likely to be a solution in isolation. the other thing is like well what other interventions besides discouraging people from eating these things are should be entertained you know you could just continue wagging your finger at people or you could argue for more aggressive regulation of the food industry you could incentivize reformulation by industry towards more healthful things of which they might say oh well banning food dyes is part of that uh you know reformulation idea and it's like okay well If that's your first increment, what's the next increment?

1:19:41Dr. Austin Baraki:What's coming next? Lay the plan out. Yeah, show me the roadmap for how we're going to achieve that. So yeah, it's just insanely complex. That's why it's been such a difficult nut to crack over all these decades. Some countries, I've seen some recent data that some countries have actually modified their population trajectory of obesity downward. I think Spain is one of them, and I forget the other one off the top of my head. So it seems like it is possible. We just operate in a very different socio-political, economic, regulatory framework here with a lot more interests or different interests at play.

1:20:19Dr. Austin Baraki:So that was a lot of thoughts. But yeah, this is an interesting one, but just, gosh, it's so hard.

1:20:23Dr. Jordan Feigenbaum:Yeah, I think we – yeah, we agree that – and most public health agencies would agree with us that, yep, we should be taking in less ultra-processed foods generally speaking. No argument there. That's not particularly controversial. What is maybe more controversial is I don't know and I don't think that advising people to eat less ultra-processed foods or processed foods generally speaking is a great actionable tip. One, people – this whole processing like categorization system is made up, right, and creates some confusion. For example, a lot of foods that could be health-promoting are processed or an ultra-processed, not as many as would be potentially harmful I guess you would say.

1:21:07Dr. Jordan Feigenbaum:But like making decisions about what foods to buy, prepare, eat, particularly inside the home. I don't know that like having a traffic light system on like ultra-processed versus minimally processed is going to be meaningful. That's speculative. You could do something like that just to see. I just don't think so because even amongst professionals, there's discussion about like, can we really say that this is ultra processed and bad versus this is minimally processed and good? And ultimately in the study even, they lost weight on ultra processed food-based diets. It's – so it is possible and to something you said often, it's like the more food that you eat that is not particularly satiating, that does have some of these elements of what we would call like a hedonic response to food.

1:21:51Dr. Jordan Feigenbaum:So – and these foods tend to have more added sugar, more added sodium, salt, more added fats. It's going to require more conscious decision-making to the extent that's possible about regulating your food intake whereas a minimally processed or unprocessed food diet, if that was the majority of your dietary intake, you're going to kind of default your way into a health-promoting dietary pattern sometimes.

1:22:12Dr. Austin Baraki:Yeah. But the people who are genetically set up in a favorable way for that environment are going to be more likely to self-regulate in an adaptive fashion. They're still going to be outliers. But yeah, it sets you up for the potential of success a greater proportion of the time.

1:22:28Dr. Jordan Feigenbaum:Yeah. If I had to pick more research to happen on ultra-processed foods going forward, I'd probably take the Kevin Hall approach where you're trying to identify specific mechanisms of ultra-processed foods that are uniquely, quote, fattening or harmful, right, such that those would be targets for potential policy interventions like food science regulations and stuff like that. Because if you could identify all these things that make ultra-processed foods more likely to be overconsumed, right, and you could fix them, quote, unquote, then you wouldn't, you know, you could continue to have ultra-processed foods that by and large are cheaper, by and large, you know, would be accessible for folks, but they would just be health promoting at this time instead of harm.

1:23:11Dr. Jordan Feigenbaum:So my wrapping all this up in like a quick little soundbite sort of thing is I think that if we had to make some changes and what we take from this paper is we need to change the food environment and change the way that people respond to the food environment. So coming at it from both ends and that gives me, it leads me to the three Ms. Again, something I've always said. Always said forever and ever. First M is marketing. There needs to be, I think, either some regulation or some policy related to marketing of ultra-processed foods to not only the public but particularly kids. There are textbooks in elementary schools that have like branded advertisements for very cereal brands and like cookies and sweets and stuff like that because they paid for the books.

1:23:57Dr. Jordan Feigenbaum:And so they're in there and it's like I don't know that I feel great about that or cartoon characters for kids on these foods. They probably should not be eating. So marketing is one. Why are these foods so desirable, for example? The second M is monitoring what's going on in food science, what's going on with average portion size, what's going on with eating practices outside the home because those would change various policy approaches. if people are eating all of these foods, all these meals outside of the home, then we should make sure that the proportions aren't crazy. We should make sure – I mean if you're coming at this from a policy approach, although some people would say, I don't want government in my restaurants.

1:24:35Dr. Jordan Feigenbaum:Sure. Okay, fair enough. That's the second M, some sort of monitoring because we're kind of flying blind here, like what's really happening. And then the third part here is meds because that's one thing – one distinct way you can get people to change the way that they respond to this modern food environment. If you make people get more full, more satiated, sooner they're going to eat less calories. And despite the food environment being obesogenic, they're going to be able to achieve a healthier body composition and body weight, largely speaking, with these medications like GLP-1 receptor agonists and some of the meds in the future.

1:25:13Dr. Jordan Feigenbaum:And so I think that we would advise a two-pronged approach. Let's fix the environment and let's make sure that people are responding to the environment in a better way and use all the tools that we have available to do so.

1:25:28Dr. Austin Baraki:Yeah, I think that that would be a more likely strategy to get us to where – or at least to bend that trajectory and get us headed in the direction we would prefer to see from a population health standpoint than anything that we're really doing actively right now. Yeah.

1:25:43Dr. Jordan Feigenbaum:Red dye 40 removal, not going to move the needle. Beef tallow being promoted is like a healthier option, not going to move the needle. And further, none of these things really address the food environment because those things weren't causal of the food environment being what it is right now. And so it's like I'm in favor of change, to be clear. I just think that these changes should be based on existing evidence or at least plausibility. And then we got to see, you know, it's just complicated. And most things are. Most things are. All right. Well, that is a wrap here on the Barbell Medicine podcast, the September 2025 research review.

1:26:23Dr. Jordan Feigenbaum:Special shout out to Dr. Austin Baraki for joining us on the podcast. Before you guys go anywhere, please leave us a five star rating and a review. It really helps drive traffic to our podcast so we can keep bringing you all the latest nuance and health and fitness. From everyone here at Barbell Medicine, I'm Dr. Jordan Weigenbaum. We'll catch you next week and every week right here on the Barbell Medicine Podcast.