Response: How Critical MAS would tackle serious weight loss

Many roads lead to Rome. And by Rome I mean normal weight.

Ok, hear me out: Arrival but with a potato

If you’re not familiar, Critical MAS is a blogger from Seattle. He frequently posts interesting content on health topics including diet, working out with a focus on longevity and flexibility, and more. I enjoy his writing and his perspective, although I don’t always agree. (For example, I think he’s pretty wrong on keto.)

Inspired by the comments on a recent blog post of his, Critical MAS has published a post titled How I Would Tackle Serious Weight Loss.

As “Serious Weight Loss” is the middle name of this blog here at ExFatloss, I thought I’d go through his ideas and comment. I do agree with quite a bit here, and, interestingly, Critical MAS has been doing what Brad Marshall from Fire in a Bottle would call an “emergence diet” for years - low in PUFAs and protein, mostly starch. Critical MAS calls this a Modern Peasant Diet, but more on it later. He’s also a big proponent of the Potato Diet.

I encourage you to read the whole article as it’s well written and has some pretty good insights from MAS’ own weight loss journey from 222lbs down to 180lbs, a weight he has now maintained for 4 years.

Defining Serious Weight Loss

MAS begins by separating his weight loss journey into 2 phases. The border isn’t exactly clear or objectively defined by any sort of marker or theory, he just picked 200lbs to “switch gears,” which cuts his total weight loss roughly in half.

• 222 → 200lbs: “Serious” weight loss. MAS is 6’2 1/2 and had decided 200lbs would be a good goal weight.

• 200 → 180lbs: “Red Zone” weight loss, named after the final 20 yards in football, where a team’s strategy often has to change since the defending team can now focus all their efforts on this small area.

I like this split. Just following different people and their weight loss over the years, it does seem pretty obvious that very overweight or obese people require different tactics than relatively normal or lean people who want to get leaner.

For reference, at 6’2 1/2 MAS would have started at a BMI of just over 28 (222lbs), switched gears at just over BMI 25 (200lbs), which is the line for “normal weight/overweight,” and finally stabilized at just under BMI 23 (180lbs).

If you asked me to pick a random Schelling point for switching gears, reaching “normal weight” might’ve just been it, hah. For even more reference, 200lbs was also the point I easily reached previously after losing about 100lbs. I ended up switching gears, but in all the wrong ways ;-)

How serious is serious weight loss?

Without trying to sound like a dick here, I think a total loss of 40lbs is very respectable, but not exactly an extreme case. I long considered fluctuations of 30lbs pretty normal.

With a high of BMI 28, MAS was never quite obese, if upper-middle overweight. I’m down 60lbs in the last 12 months and I’m almost exactly 10lbs above his starting weight - while being an inch shorter.

That said, even for his 40lbs MAS discovered that there was a useful split, and that there are appropriate strategies for either phase.

The “serious” phase

MAS recommends using a low-fat, whole-foods diet. He focuses on using foods that taste just “OK” and not overly delicious. The food should be boring, and high in fiber. This is presumably to make use of the “food reward” theory of obesity, which says that we overeat foods that are “too delicious” (or technically, too palatable, which I believe is slightly different).

He does recommend eating to satiety at every meal, which I whole-heartedly agree with.

For this phase, he also recommends the potato diet and his Modern Peasant Diet. Let’s take a look at this real quick, as the name intrigues!

Modern Peasant Diet

The moniker comes from the idea that if we imagine a peasant eating food, we’re not imagining cakes, ultra-processed foods, or other modern, industrial cuisine. We probably imagine something simple, probably somewhat boring and repetitive, rustic, yet nutritious. Peasants did, after all, perform a lot of hard physical labor.

(It’s interesting that if we imagine a modern American farmer’s diet, we’re probably thinking the opposite. The food choices in rural America these days tend to be abysmal unless home-cooked.)

MAS cites Stephan Guyenet, author of The Hungry Brain, and a big proponent of the Food Reward theory of Obesity, as inspiration for this diet.

Staples on the MPD are potatoes, beans, oats, something called “farro” (apparently unmilled wheat grain?), eggs, pork, and chicken.

MAS doesn’t eat “like a peasant” every day, or at least wasn’t at the time he coined the diet. He says 60-70% of the time is enough.

Thoughts on the Food Reward theory of Obesity

I’m torn on it, honestly. I haven’t entirely ruled it out, but I vaguely disagree with it because it only matches my own experience very selectively. And it doesn’t seem to match the experience of some of the people I know at all.

For example, I just reached my lowest weight in over 6 years eating chocolate truffle, with chocolate being the substance Stephan Guyenet describes as maybe the most addictive of all rewarding foods, comparing it to a drug.

On the other hand, I ended up HATING the chocolate truffle after day 4.

On a slightly different part of the spectrum of food reward, my daily meal on ex150 consists of 150g of beef, 60g of vegetables, and 80g of tomato or alfredo sauce. This meal, to me, is the most rewarding meal I can imagine. I burn the beef nearly to the ground, I cook the tomato sauce way down on low. I don’t even add salt, pepper, or other spices, just whatever is in the pasta sauce. And it’s just amazing, even after eating it nearly every day for over a year straight.

But I don’t eat that meal ad libitum - the portion is very small, and predetermined.

Later, I eat heavy cream to satiety - maybe heavy cream on its own, or just with instant coffee powder as I typically eat it, is “peasant approved?” In terms of food reward, it certainly isn’t a stunner. I really like heavy cream, but it’s not as amazing as ground beef with tomato sauce, or as the first bite of chocolate truffle after you haven’t had it in a while.

On the other hand, heavy cream also doesn’t get as boring/nearly sickening as chocolate truffle does, although chocolate truffle is just heavy cream with chocolate emulsified in.

So it could be that you want your ad-libitum foods to have a sort of “Goldilocks Food Reward” quality to them. Something you could eat daily, or near-daily, indefinitely. But not so rewarding/delightful that you’d continue eating simply for the pleasure of it, as I almost certainly would if I had infinite amounts of ground beef with tomato sauce.

Or is “palatability” a red herring, and it’s really the composition of a food that makes it suitable or not? Can we separate palatability from composition?

The technical definition of palatability

Let’s briefly talk about palatability. It often gets conflated with “delicious” or “tastes good.” But I don’t think anybody would argue that a Twinkie tastes better than an authentic Italian gelato. Or that McDonald’s meals taste better than home-cooked food by grandma.

In fact, while modern American junk food is considered peak hyper-palatable, very few people around the world think of it as haute cuisine. Even Americans would likely admit that a home-made sandwich tastes better than most fast food.

What palatability technically seems to mean is simply that it makes you eat more. This also has interplay with satiety: a food that makes you eat more could be said to be less satiating.

As my recent experiment with sour cream demonstrates, I don’t think that these are necessarily the same thing. A food can be satiating, or not very satiating, but it can also stimulate hyperphagia, which in a sense is negative satiety. You’d think that a food’s satiety couldn’t be negative, but you’d be wrong.

I believe a lot of modern “ultra-processed foods” make you acutely hyperphagic. This is usually blamed on those evil food scientists or evil corporations, designing the texture and flavor of doritos so you can’t eat just one.

But I also suspect there’s a biochemical aspect to it, because I don’t suppose any evil food scientists twirled their mustaches in a smoke-filled room to invent sour cream.

Sour cream is pretty much the exact same thing as heavy cream, except fermented a bit. The macros are a bit different and it tastes, well, sour. But the consistency and texture is very similar to that of whipped heavy cream, my staple and most-satiating food ever.

Similarly, the most “ultra-processed” food in my hyper-palatable ground beef meal is Rao’s pasta sauce, which uses very healthy, whole ingredients and was available, in terms of technology, for probably the last 300 years (or whenever tomatoes got brought to Italy).

So I’ll give the Food Reward theory a skeptical “maybe” for now.

Goal of the Modern Peasant Diet: disassociate “calories” from flavor

The stated goal of the MPD is to retrain your brain, so you don’t conflate eating with entertainment. This is supposed to drop appetite as you will basically only eat for fuel, instead of for the “hit” that eating palatable food would provide.

Of course, the entire idea behind this is that obesity is caused by eating too many “calories,” which I’m not a huge fan of.

Several other aspect to reduce the “food entertainment” MAS mentions are eating slower, and cooking most or all of your food at home.

I personally don’t think these do much if you’re already metabolically unwell - I certainly ate slow when I tried the potato diet, but I still couldn’t get in much more than 600kcal (~2lbs) per day, spread out over an entire day, yet I got bloated and felt like shit. And I gained 100lbs cooking 95-99% of my own food at home from fresh ingredients.

Eating a plate of veggies over a whole grain
or potatoes fills me up with very few calories.
- Critical MAS

I get the impression that Critical MAS, despite having lost 40lbs, never had whatever it is I have, and what I suspect many or most seriously obese people have: there is absolutely no satiety from fiber/water/volume. I’m talking nilch, nada, zip.

Case in point: my recent “salad day” on which I gained 15lbs in about as many hours eating practically calorie-free salad. Of course it was all water weight and bloaty fiber.

But the point is: there was absolutely no satiety. I stopped due to pain, not because I was “satiated” in any way.

Hence a lot of these “normal people tricks” like “eat slowly” and “eat fiber” likely won’t have much impact on somebody with severe metabolic issues.

Protein restriction

During the “Serious Phase,” MAS recommends restricting protein. He thinks that it is not necessary to eat a lot of protein if still very overweight, and that eating low protein could help minimize issues with loose skin.

I agree completely, although I don’t have any proof for the loose skin issue - but, so far, I don’t have any at 60lbs down, and I didn’t last time after losing 100lbs.

Exercise: not right away

MAS recommends not exercising in the first, “serious” phase. I agree with this, especially if we’re talking “fat burning” cardio that is often recommended for weight loss. But even strength training will increase your appetite.

I waited an entire year myself before I added in strength training, and I think it was the right choice. Maybe 8 or 10 months would’ve been fine, but I think it’s much more productive to “get lean to exercise” than to “exercise to get lean” if you’re starting out seriously overweight or obese.

MAS also recommends sauna, which I haven’t tried much.

Intermittent Fasting

MAS acknowledges that overdoing fasting can make you feel like crap and be difficult, but also that there isn’t much muscle to be lost for very overweight people. Lean people might have to worry about losing muscle when fasting too much.

He recommends to start with a daily eating window that you slowly get down from 12 to 8 hours. Then, start incorporating 1-2 day fasts.

Intriguingly, he also recommends donating blood - something my doctor has been prodding me to get into.

The “red zone” phase

The main difference in the “final approach” of weight loss seems to be to increase protein. As one becomes leaner, and possibly more active with exercise, this becomes more of an issue.

MAS himself began adding protein around 200lbs and, for a while, he did what he calls Potatoes & Protein - pretty much what it sounds like.

It sounds like he nailed the landing on switching gears from lower to higher protein. I’m interested in this gear change myself, as I hope to eventually be lean enough and able to eat more protein again.

Honestly, 200lbs is probably not an unreasonable target for me either, given that I’m nearly the same height as MAS. But we’ll see. I can always run an experiment.

Critical MAS and Modern PUFA Theory

What’s fascinating is that Critial MAS used to be a big believer in PUFA theory as far back as 2013.

The strategy he chose was to go on a low-fat diet, something that Brad Marshall and many on the r/saturatedfat subreddit are coming around to as well these days - combined with protein restriction, too!

So in a sense, MAS was ahead of his time here.

In some of his older posts he describes draining the fat from cooked chicken and even beef, and avoiding nuts & seeds entirely.

Avoiding seed oils appears to be working well for me.
I’m warm and my appetite is in check.
In a world that is getting fatter every year,
I’m the leanest I’ve ever been and the process feels effortless.
- Critical MAS

He seems to have partly abandoned that idea now, and it doesn’t even make a cameo in his post on Serious Weight Loss.

It’s slightly weird to be because in that post MAS still says that seed oils likely lower your body temperature/metabolism, even calling himself a believer in this idea. He also seems to find the Hyperlipid idea of reduced satiety from seed oils (ROS theory) persuasive.

And he still avoids seed oils himself, and talked about escaping PUFA hibernation as recently as 2021 in this excellent post.

Decide what is best for you. Experiment.
The important thing is to reduce PUFA.
- Critical MAS

Sure seems weird then that seed oils don’t show up at all in the Serious Weight Loss post. Given how militant MAS himself used to be about avoiding PUFAs, and that he still believes in half of the theory, you’d think it would get a mention.

Maybe what’s happened is that he has incorporated PUFA avoidance into his life for so long, and so thoroughly, he just doesn’t notice it anymore?

After 8 years of keto, I don’t even think of keto anymore. Most non-keto foods have long stopped being foods to me. You just get used to your ways, I suppose.

He leaves us at the end of the Serious Weight Loss post with this:

I bored myself thin with nutrient-dense high-volume fiber-rich foods.
I was never hungry and my appetite fell to support my ideal weight.
- Critical MAS

I don’t think that “boring peasant food” was completely without fault in his weight loss. But for one of the most militant PUFA avoiders I’ve ever heard of, it sure seems weird to not even mention once.

Comments by Critical MAS

After I sent a draft of this post to MAS to verify I wasn’t misunderstanding anything, he confirmed that he doesn’t even think about avoiding PUFAs any more, it’s just a habit now. It’s who he has become.

He also explained that while excluding PUFAs allowed him to ramp up and maintain his metabolism (as measured e.g. by body temperature), but he didn’t start losing weight until he started the Modern Peasant Diet.

There are many cases like this on r/saturatedfat, including Brad himself. Excluding PUFAs makes for a very enjoyable and sustainable maintenance diet, but many people seem to need to do more than just that to actively lose weight.

For example, some need to restrict protein, which is something MAS did on the Modern Peasant Diet during his “serious” phase. Others seem to require to “stay out of the metabolic swamp,” in other words, choose either a low-carb or a low-fat diet. MAS did this as well by going very low-fat.

Conclusion

Critical MAS’ story and blog are fascinating - it’s like reading somebody who went down nearly the same path I did, but 10 years prior. Somehow, when I got into Paleo in the early 2010s, I totally missed the PUFA point. I didn’t cook with seed oils, so I was fine, right? For some reason I mainly focused on the grain/gluten angle back then.

I followed the directions of Paleo gurus to eat lots of nuts & seeds, fatty pork and chicken, even nut butters. In posts from 2013 on his blog, MAS does the math on some of these Paleo types and demonstrates that some of the “Paleo” recipes actually contain 8-12% PUFA, way too high.

MAS’ success can certainly be interpreted through the Modern PUFA Theory lens, I think, and he even did the now-fashionable protein restriction. But because nutrition and biology are complicated, we of course can’t prove what caused him to reach his goal weight.

I wonder how much linoleic acid is in his red blood cell phospholipids. I’d bet it’s <11%.