It is well known that if you gain muscle then lose it, it is easier to regain it than the first time (IIRC, the cells store extra nucleii?). This could be a similar effect but with fat cells.

I believe that is the latest theory regarding the mechanism, yes.

https://pmc.ncbi.nlm.nih.gov/articles/PMC3892465/

As well as the "cell memory", the total number of fat cells you have in your body is set during adolescence, then it remains constant for the rest of your adult life. (https://www.nature.com/articles/ncpgasthep1189).

During adolescence, if you gain weight, you create new fat cells. During adulthood, the fat cells themselves just get larger. Arguably the best thing you can do is avoid obesity during childhood and adolescence at all costs.

Interested parties may want to read the original article https://doi.org/10.1038/nature06902 in place of the highlight https://doi.org/10.1038/ncpgasthep1189.

> During adulthood, the fat cells themselves just get larger.

While true, it's also important to note that the lifetime of a fat cell is around ten years. Maintaining a decent diet for around ten years (no mean feat!) should be sufficient to leave you bereft of the actual adipose cells.

I also wonder how this intersects with transgender stuff — there's a reason why HRT is referred to as "second puberty", as it resets and changes a lot of underlying biological mechanisms and produces a lot of interesting epigenetic effects (While it does boil down to "replacing the sex hormone", both estrogen and testosterone have major effects on the body's immune system, etc. — actually this is one of the reasons I suspect that there's such a high comorbidity of autoimmune diseases within transgender people pre-HRT — their immune system is all out of wack! Mine calmed down a lot after starting and a year in I no longer get seasonal allergies). There's a huge lack of data in this regard though because transgender bodies are generally not felt to be worth studying outside of "health risks", even though there's a huge amount of information we could glean about how everyone's* body functions from it. Personally, I wonder whether second-puberty "resets" what the body decides is the baseline for fat storage.

* — and for anyone in doubt, we have around 90 years of HRT now that shows it's essentially completely safe (outside of the mid-80s when the estrogen being given was synthetic and non-bio-identical, and outside of the health risks of various things for trans women changing to be roughly equivalent of cis women's health risks).

metabolism is orthogonal . It's possible to have a fast metabolism and still be obese if you're eating at a surplus. But it's also possible people with faster metabolisms may be more successful at weight loss if already obese. So a 300-lbs person who eats 10,000 calories/day to be weight stable will find it easier to lose weight compared to to a 300 lbs person who is stable at 4,000 cal/day. This can also explain how some people lose tons of weight on GLP-1 drugs, whereas others lose less. The guy eating 10,000 calories/day will lose much more weight more rapidly owning to having a much bigger metabolic furnace, as soon as he restricts eating and his body is no longer getting 10,000 calories/day. Unfortunately, there are no studies that investigate the link, if any, with metabolism and dieting success.

10k calories a day is what a black bear eats preparing for hibernation. And it is what Michael Phelps would eat daily when training in the pool for hours on end.

Obese people can remain obese eating 1000 calories a day. I recall one episode of My 600lb Life and the show's featured person that day was at 900 or 1200 calories a day and still didn't lose weight. Might have still been gaining.

It is a dynamic system. People tend to only consider the CI in CI/CO.

>Obese people can remain obese eating 1000 calories a day. I recall one episode of My 600lb Life and the show's featured person that day was at 900 or 1200 calories a day and still didn't lose weight. Might have still been gaining.

How is that possible? There is a lower bound on calories needed (on average across say six months) to maintain life. Adding to that the calories needed to maintain the weight, I don't see how an obese person could stay alive with "CO" significantly lower than 1200 kcal.

And yet it happens. A doctor in my family told the story of a patient they were treating in hospital who medically needed to lose weight, and who they found unable to get any reduction until they dropped below _200_ calories a day.

Metabolism is _significantly_ more complex than CI/CO, from experience.

What is more likely:

- a physics-breaking thermodynamic anomaly

- a food addicted person is lying about their consumption

200 kcal a day.. yeah sure. A human body needs more than that just to breathe and pump blood. Even comatose a skinny person needs 5 times as much.

Overweight people have a significantly higher metabolic base rate. Just breathing can easily be 1000kcal a day if your lungs have to move 30 kilos of upper body fat 10 times a minute. They also have more muscle mass compared to the average person their size, even when not physically active, which increases MBR as well.

Weight loss and gain is a solved problem, but self control and human behavior is not.

Perpetuating myths of impossible weight loss is not beneficial for our society and moves us further away from solving the underlying issues.

It's insane how arrogant people can be about this. You have not accounted for all of the variables and that is blatantly obvious. The phenomenon is well known and there are multi-variable equations for it, many different models. One popular model is that NEET can decrease below the caloric deficit, meaning you still gain weight by becoming subconsciously lazier despite everything feeling equally difficult subjectively. There are several other more advanced models adding other variables, some depending on insulin sensitivity, for example. Anyway, no physics is broken, laymen are just naive to the complexity abd adaptability of biology.

200kcal/day is less than 10W. Since all energy the body uses is released as heat this puts the maximum sustainable heat radiation with such a diet at 10W.

That's about the level of a typical household LED, which at most feels slightly warm to the touch.

At that energy level you could not sustain weight while maintaining body temperature let alone having a healthy metabolism. That's just a plain fact.

You will lose weight long before you reach 200kcal/day.

That's a good argument against what I said for this particular case. I didn't realize 200kcal was so little. Imagine my comment was written in reply to a higher number though because that criticism is definitely valid for a large number of posts people make in general. ;)

But it is basic physics, which is in fact being violated. It's really very normal to require exceptional proof for this. Like literally any scientific study, not just an anecdote claiming magic.

Basic physics says CI/CO applies to a closed system. Show me a closed system human and then it will be applicable.

E=MC^2 is basic physics too. So eat a pea and have enough calories for the rest of your life and then some?

You are implying that humans receive energy from another source, which is an extraordinary claim that you should motivate somehow.

Nutritional science is pseudo science at best. I had rather continue to believe in thermodynamics lmao

It is the amazing the hoops people will jump through and the lies they will tell themselves and others rather than facing the obvious truth that they are consuming too many calories.

If you treat humans as biological machines, signaling system (hormones, endocrine system) is very important. When signaling system is messed up, your CI/CO model with self-control doesn't work at all. Signals need to be fixed.

So? That doesn't disprove the premise of CI/CO. CI/CO is the notion that humans exist in the physical world and thus obey the laws of thermodynamics.

CI + self-control or will --> CO (that's the hypothesis sold by many)

CI + hormones --> CO (that's an alternative hypothesis)

> Weight loss and gain is a solved problem, but self control and human behavior is not.

Semaglutide and tirzepatide address the self control and human behavior problems. They stop you from wanting to eat more.

I can believe this as a human who fasts. I just don't eat every other day. I've fasted for multiple days. You would amazed at how much the scale doesn't move. I can lose zero weight after 36 hours of nothing but water entering me. The body is less CICO and more a system trying to maintain homeostasis as much as possible and pulling ever lever it can.

Yes, eventually eating every other day I did lose weight, but we're talking a steady glide of 1-2lbs a week nothing as severe as people would expect a severely overweight person who only ate half the week to lose.

You cant cheat thermodynamics, so something does not add up. Most likely the calorie estimates if they were self reported.

To illustrate a single 37.5g snickers is slightly below 200kcal. I probably get that number of calories just from the milk in my coffee in an average day.

Whole milk (3.25% fat) is ~60kcals per 100grams. Are you really drinking 300+grams of whole milk in your coffee per day?

For how long? Irregularities can persist for a small amount of time, no doubt; but for how long does one maintain weight and life on 300 calories a day?

Come on, this is ridiculous.

CI/CO is a thing.

https://en.m.wikipedia.org/wiki/Thermodynamics

Agreeing and I found it interesting to learn more about caloric availability to the body.

I.e. calories on the label vs what the body can actually access.

Like drinking smoothies (high availability) vs raw fruit (lower availability)

Dr. Greger (Nutrition focused) discusses some of this on calorie density and some referenced studies here if interested:

https://nutritionfacts.org/blog/how-to-lose-weight-eating-mo...

I don't believe that people can gain weight while eating almost nothing, but I believe that their internal distribution of energy may be out of whack.

Proponents of naive thermodynamics model tend to assume that only "excessive" energy is stored into bodily fat, once all the other tissues have had their fair share.

That is not really true in insulin resistant people, whose storage may be excessive and leave the rest of the body unsatisfied and hungry, which drives them to eat more than a healthy person would.

To us, this looks like deliberate overeating, to them, it is a result of constant hunger caused by the fact that some part of the energy consumed is being immediately locked away in fat tissues by dysregulated metabolic processes.

Notably, it isn't easy to "correct" this situation by just eating less, because that will leave those people feeling really starved. Insulin sensitivity must be restored first, then the fat stores will give up their excess willingly and that person won't suffer.

1000 calories is already an unbelievable claim, absolutely no one is going to believe 200. That’s just absurd

> "How is that possible?"

Eat 1200 Calories per day, drink 5Kg of water, water retention, body mass and scale weight goes up with increasing water weight?

It happens because we act like calories are calories when it's clearly not true.

Calorie counts in nutrition data are generated by something like burning the food in a bomb calorimeter. Which is most definitely not what our bodies do. We have all kinds of different biochemical ways of metabolizing different types of foods.

So someone eating 1000 calories of day could be eating very healthy or they could be ingesting a whole bunch of garbage full of sweeteners. It doesn't seem like anyone really understands how it works but all those sweeteners are more likely to make you gain weight.

Why is it that people claim the laws of thermodynamics do not apply to humans?

Because our metabolisation mechanisms are extremely complex and many things, like genetics, decide how we metabolise food; we are not petrol engines.

Obviously the laws of thermodynamics apply, but the most naive application of the laws of thermodynamics doesn't.

A human body isn't a bomb calorimeter and it doesn't perfectly combust everything you eat.

No one is claiming that the laws of thermodynamics do not apply to humans.

I'm sure an obese person claiming to eat 1000kcal per day can still gain weight but that is largely due to selfreported calorie estimates being a bad measure. Put that person in a chamber where calorie intake is controlled and I'd bet the effect disappears.

Ate only 1000kcal in food. Added in 1400kcal in sugary drinks and 2000kcal in small bites of this and that (that don't need to be counted, because it's just one spoonful of peanut butter!)

The small bites have doomed me in the past until I charted and realized the impact.

Yeah, I don't know if it was that episode or from somewhere else, but there was a similar thing where they followed the person around for a day and it turned out they didn't count anything ate as a snack between meals. They were accurately counting their meals, but including the snacks went somewhere above 3000 a day.

Secret eaters, a British show.

As somebody who went through successful weight cuts at least 3 times I must notice that not losing weight on 200 calories a day is... a very unrealistic situation. Even a 1000 calories is starving.

(I do weightlifting, and controlling one's weight is basics of everything in the gym)

This is completely and obviously untrue.

Please share your bro science video. I need it :)

If you want the serious science about low carb/keto, I recommend the “Low Carb Down Under” channel on Youtube.

A lot of people blame failure to lose fat on a "slow metabolism" but this is usually incorrect. Have you had an actual resting metabolic rate (RMR) test to quantity your baseline total daily energy expenditure?

Fat adaptation is a real thing. Endurance athletes focused on longer events will target some of their training around that energy system. This is more complex than can really be explained in an online comment but basically you want to do long training sessions below your lactate threshold in a glycogen depleted state.

They didn't mean it was literally a slow metabolism. They meant that what the article is about is often refered to as a "slow metabolism". It's a misnomer since that is not the mechanism but there is definitely a phenomenon at play, which is what the article is about, the actual phenomenon rather than the bro science.

There is also a conflation of a slowing metabolism and low energy availability, which can reduce the amount of energy expended during the day (because you feel tired and do less). It can be quite subtle but when I've done some extended periods in a calorie deficit I start to notice subtle things, like a propensity to sit a bit longer, or to reduce my overall body movements. My resting metabolism is the same (I've had it measured a few times) but my body looks for ways to expend less energy.

Anecdotally (but an experience shared at by at least some other long distance runners), when I get quite far into a calorie deficit via exercise, my brain will start suggesting shortcuts - urges to cut the corner on a trail, take a shorter path back etc. Its quite interesting!

Considering the amount of effort it traditionally took to get food it's a shame that our brains would want us to be less active when it could otherwise start suggesting that we be even more active to find/hunt food.

The suggestions generally still work towards my goal; this is a different phenomena to "holy shit the consciousness is trying to kill us again" panic switch. Maybe its some low level optimisation to reduce energy expenditure, so we can last longer, and find even more food!

More than that, your body downregulates unconscious activity (known as NEAT). This reduces fidgeting and even influences how likely you are to get up, say if you're thirsty or have to pee. In a caloric deficit, you're more likely to just "decide" to not get up to get that drink.

I think you missed the point that he said "slow metabolism" is just a colloquial term for something else.

them and the rest of society

Insulin sensitivity is a real thing. The less sensitive to insulin you are, the more of it is produced to process a given amount of glucose. And the more insulin (anabolic) is produced, the less glucagon (catabolic) is.

In other words, low insulin sensitivity means your body remains in the feeding (fat building) state more, as opposed to fasting (fat burning).

Insulin sensitivity decreases with age, and with excessive intake of particularly simple carbs. It can be improved through fasting, certain dietary supplements, and low carb diet.

All of this is, to the best of my knowledge, not disputed or 'bro science'.

If there really was a gene that allowed you to survive on substantially less food than your peers, pretty much all humans would have said gene. The history of humanity is rife with famine, and that gene would be a game-changer for survival

It's all about tradeoffs. In this case, I wonder if there's an "efficient metabolism" gene that makes your body put a higher percentage of incoming nutrients into long-term storage (mostly in fat tissue). Carriers of this gene would be more likely to survive a famine, but less likely to outrun a predator or defend against an attack by another leaner human, who's genes allocate incoming nutrients to be utilized more effectively in the short-term.

Look into Polynesian peoples. They survived long sea voyages, and are known to be generally large people in modern day. Like the guy at my high school whose nickname was "Big Tonga"

Samoan have a high degree of a particular variant of gene CREBRF that's highly associated with high BMI (see https://doi.org/10.1038/ng.3620). Pop-Sci says it's an adaptation to the life in an island (might also be a founder effect?)

...don't we? According to [0], the amount of food (by energy intake) people get is very diverse worldwide. People can survive famine situations for a long time, and people' problems with obesity is linked to exactly those survival genes.

Granted, some animals are much better at it, crocodiles and bears and stuff can go without food for months.

[0] https://en.wikipedia.org/wiki/List_of_countries_by_food_ener...

I think it’s quite the opposite because it would not be a gene that allows you to survive on less food - it would be a gene that favors replacing glycogen stores over lipid stores. That kind of mechanism would be pretty negative to survival until the modern era of sedentary civilization.

The physical mechanism is mitochondrial uncoupling proteins (UCP). They regulate how much energy is wasted as heat when converting ADP to ATP, determining how efficient one’s metabolism is. When you lose weight, your UCP proteins start wasting less and less energy when producing ATP, which is one of the things that makes dieting so hard.

Actually affecting that pathway is largely beyond us at the moment (that’s the bro science) but the mechanism is relatively well understood.

Is this similar to what 2, 4 dinitrophenol affects?

Yes, sort of. DNP doesn’t affect uncoupling proteins directly but it moves protons across the mitochondrial membrane, causing more of the energy to be lost as heat as the uncoupling proteins waste more energy to restore the proton gradient.

There are a bunch of such “protonophores” that move protons across membranes and they are universally toxic if they make it to the mitochondria. I don’t known of any compound that actually mediates the UCPs themselves.

>but I wonder how much of that is bro science and how much of it is grounded in reality

It's probably bro science or contributing a small amount to any effort. The biggest problem is the food industry serving shit in large portions, which can be hard for populations to psychologically resist (see: America). Most things in the grocery store are shit too.

I don't think you can effectively teach people to resist it though, you'd have to get rid of the shit being there so it's not even an option.

That's how my brother lost weight finally. He just never bought any of the stuff - so it wasn't even in his house. But he lives alone right now so if you live in a group setting you might be, in weak moments, snacking on bad things that other people brought in. It's kind of also why I don't think companies should provide candy machines etc.

For me, sugar was the reason I couldn't lose weight. I got a CGM (continuous glucose monitor) and got my blood sugar under control, and with very little effort I lost a lot of weight.

I use 90% cacao Lindt to control my sweet tooth. 1/2 the bar has 4g of sugar, and I consume it over hours. It also has the side effect of reducing my hunger. If you eat much of 90% chocolate, it makes you feel nausea. The trick is to put a small chip in your mouth and let it melt. It's quite delicious and I've not had any sweets in 80+ days.

This also speaks to another point, when trying to lose weight: you must find new things to enjoy.

This is actually great advice for any bad habit you're trying to break. In general, just thinking "Stop doing this thing" (or "do less of this thing"), doesn't really work. It's usually more effective to find something else that you do enjoy (and is better for you), and try to do more of that thing and have it "crowd out" your bad habit.

When it comes to eating, there is a nutritionist with a pretty sizable online following (Kylie Sakaida), and I love one of her mantras of "add, don't subtract". That is, don't think of abstaining from foods you like that might be unhealthy, but instead try to add more healthy things to that food to make it a balanced meal. For example, she gives the example of wanting a frozen waffle for breakfast. Instead of thinking "No, I can't have this frozen waffle", she instead makes a spread using Greek yogurt to add protein, then adds fresh fruit and nuts for more nutrients, fiber and healthy fats, so what started as an 'empty carbs' meal is turned into a pretty balanced, filling breakfast.

So true. I've done this very often:

- See some goodies my wife bought (for herself or me).

- Thinks about having my 90% Lindt later/next day.

- Walks away.

I was realizing that spicy food can be that.

I’d be interested to hear more here - what CGM did you buy? What was your process for monitoring?

The Stelo. 2 for $99. Oddly, it shipped from Amazon but Amazon doesn't sell them.

The app is subpar on iOS, but if you give Apple's Health app permission, you can get more data in there. Graphs that have absolute numbers. I think they reason their app doesn't give absolute values (for historical values, they give the current value only), is because it's not a calibrated device. It can't be used to control an insulin pump, for that reason.

Does that imply you are paying $99 / month?

No, this was a one-time thing for me, to work out how food impacts my blood sugar. I've used 1 of the 2 I bought, and I plan to use the other in 3-4 months, to see how I react then, after 6+ months with low sugar intake.

I just completed two weeks with Lingo by Abbott. It was decent. I wish it had better integration of the data with Apple Health, but I liked the Lingo score as a way of "gamifying" it and the UX overall was decently done.

This worked for me for a while but I learned to love dark chocolate toooooo much.

I can now eat a 100g bar of 100% chocolate in a single sitting if I feel like it… And that’s 55g of fat, so more or less the fat I should be eating in a whole day.

Wow!! I feel queasy if I eat more than 1/2 a bar of the 90%. It also completely takes the edge off my hunger, which is great for me.

I think I started getting addicted to the caffeine

Interesting. I do go days without it and don't have headaches, as I would expect from caffeine withdrawal, so I guess I don't eat enough. What happens when you stop for a day or two?

I just really craved it!

In the end I just accepted I wanted to have caffeine and started drinking coffee instead.

That’s made it easier to have a few squares here and there and enjoy them properly. Which is good because chocolate good enough to eat at 100% is not cheap! Eating a whole bar a day was an expensive habbit.

I thought a CGM would help me lose weight but it turned out my body is a hero at managing sugar spikes. A pint of ice cream? Back to baseline in under an hour. Big meal, no big spike, etc.

So it turns out you can still gain weight even if you don’t spike your blood sugar. At least for me.

If you don't spike your blood sugar and you eat fewer calories that you need, I don't know how you wouldn't lose weight.

For me, a small piece of pie after dinner impacted my BS for 6-12 hours, according to the sensor. That was shocking.

I was high calorie, low spike.

I had just assumed before the cgm that my blood sugar regulation would be terrible with how easily I put in fat. But it was extremely well run.

Isn't 90% Lindt the worst (of their chocolates) for Cadmium and other heavy metals though?

All I could find is this: https://www.snopes.com/news/2024/12/31/lindt-chocolate-heavy...

I am worried about it. Ugh.

Here's one (besides CR & asyousow tests) from 2022 from the ConsumerLab

https://www.ahealthylife.nl/wp-content/uploads/2023/01/DarkC...

I'm a chocolate fan myself and it was something I used to buy often, but just as I started getting into the hard stuff (80% or higher) I learned about all the problems with heavy metals in dark chocolate and specifically in Lindt, and then later learned about the use of child slaves which is an industry wide issue and not exclusive to Lindt/Russell Stover/Ghirardelli/Lindor although Lindt and Hershey are reportedly worse than other brands.

You can find brands that claim to be more ethical in terms of sourcing their cocoa, but the smaller brands that do are also less likely to have been tested for heavy metals.

While it's unclear how harmful the heavy metals would be to me specifically at the amounts I was eating, the whole thing kind of put me off chocolate in general and dark chocolate in particular. I rarely have it anymore.

> It always did feel like it was easier to gain weight than lose it, especially fat weight and not muscle weight for me.

It is the exact, polar opposite for me. I cannot gain even if I eat junk all day.

I used to think the same. I would guess that you do not have a big breakfast. Without getting a real meal in for breakfast, hitting a huge calorie surplus is difficult. If you counted your calories and tried to get a 1000 calorie meal for breakfast, hit 3000 calories a day, you’d probably gain 10% in a few weeks. Weight training is good too… you don’t want to just gain fat.

1000 calorie breakfast = bagel with cream cheese, 3 eggs, banana, some berries, protein shake. It’s a whole lot more than a bowl of cereal.

Or go get some fast food. Plenty of them in the US can easily top out at around your daily requirement.

In college, I used to treat myself with a Hardee's sourdough Frisco burger because, for some reason, it was really damn good to me. Then I saw the calorie count: https://www.hardees.com/menu/charbroiled-burgers/hardees-fri...

Add on some fries, regular soda if that's your thing, and you are pretty much at the daily recommendation.

I tried eating all that, not just for breakfast, but 3-4 times a day, give or take, sans berries and banana.

I had a friend who was trying to bulk up make that claim (he was 6', 140 lbs), and then when I finally convinced him to write down everything he ate in a day, it was like 1800 calories.

I should do that, too, TBH.

drink milkshakes

I drink a protein shake 2 times at least, and eat lunch (chicken & rice & broccoli casserole, so forth) 2-3 times a day. I do not eat small portions either.

That only looks like about 2000 calories a day, which is the recommended caloric intake for the average sedentary adult man.

If you're trying to bulk, you need to be looking at 2500 or more calories a day, plus additional for any calories burned by exercise. (With a surplus of 1000/calories a day you'll be gaining more fat than muscle unless you're still in puberty. Sometimes that may be what you want.)

It just seems like I have to spend most of my day eating. :/

I think part of this can be solved by "hacks" the primary one being throwing olive oil on random stuff you eat. Another one is "drinking your calories". Basically all the things people tell you to do to lose weight, do the opposite

I get what you mean, sounds reasonable. :D

It's hard for me to gain weight. But in my 30s, for a few months I was eating 3000 calories plus. My breakfast smoothie was about 800 calories - 2-3 scoops protein, a banana, almond butter. I gained about 5 pounds after 3 months. It was just too hard to eat that much while also eating healthy.

I agree. To gain, I have to take an SSRI antidepressant to make me hungry, and then eat >4 packs of ramen (fake soup) among other things. Quite unhealthy.

Jason Fung is probably the world's leading research expert on obesity. If you want videos to watch on it, it starts and ends with this guy. He has done a ton of lectures and blogposts going back over a decade, and also has the stereotypical clickbaity YouTube videos.

https://www.youtube.com/watch?v=YpllomiDMX0

He has surely dedicated a significant portion of his life to his own pet theories on obesity, but to consider him a well-regarded expert is very misleading.

He has quite a few claims that are just...ridiculous, and his pop science books have some serious flaws (as reported by actual experts).

While I don't doubt you, it would be helpful if you cited these experts, so people can learn.

Fat adaptation is not bro science, it is what happens when you do not consume enough carbohydrates to meet your TDEE so your mitochondria “learn” to become really efficient at burning fatty acids. It’s the whole premise behind keto/low carb. When used to our modern high-carb diets, the adaptation takes some time for genes to activate, since we eat a lot and never have long enough fasting periods to be able to quickly switch between glucose and fatty acid metabolism.

I have had a slow metabolism since I was a teenager. I don't think I've ever experienced a day in my life where I haven't thought about my weight, body composition, or felt guilty about eating food. And I'm not even that big. I've just never had the physique I wanted, and I always attributed it to having a slow metabolism.

I'm turning 40 in May, so since the start of February, I've finally pulled up my bootstraps and started taking my health seriously. I was likely 225 lbs at 5'10". Easily 32+% body fat.

The first thing I did was a deep extended fast, drinking only water, electrolytes, supplements, bone broth, and black coffee. I was able to shed a good amount of weight, fast. However, the longest I could fast for was 6 days; No matter what I tried, I could not figure out how to get good sleep. I tried once more for 4 days, and saw no improvement, so I stopped trying to fast. Mentally I could handle it, but without quality sleep, there was no way I could continue. This was mid-March, and I was at 204.5 lbs.

Also in mid-March, I did a VO2 max test, while fasted for 72 hours. It was very apparent that my metabolism was fat adapted. My VO2 max was very low at 33.8 ml/kg, which was to be expected. My RMR was found to be 1998 kcal/day, and my fat max HR was 161 bpm. Crossover to 100% carbs was at 179 bpm.

Since then, I've done a 180, and started eating about 1800-2000 kcal per day. My first goal is to ensure I eat 170-200g of protein per day, through as much whole food as possible, using whey or protein when needed. The rest of my diet is very clean, with no real restrictions on fats, and keeping carbs as low as possible. It's a fairly ketogenic diet, but I don't get worked up if my net carbs go to 50+g. Foods are usually Greek yogurt, flax, pumpkin seeds, nuts, eggs, berries, fish, poultry, and green vegetables/salads. If I ever add fat to anything, it's extra virgin olive oil first, then maybe butter/cream (i.e. in coffee). I take a number of supplements like Omega-3 fish oils, multivitamins, magnesium, and make my own electrolyte drink. Creatine as well.

I find that by the time I've done all of this, I have a very difficult time eating, and even trying to fit anything else in. I am never hungry, nor do I feel cravings for other foods. We just came back from Miami, and I had some ice cream with the kids, and some baked goods. I enjoyed them, but I was very excited to be back to my normal foods.

Since then, I've been running 3-4 times a week, focusing on Zone 2 training. I do 4 days a week of weightlifting, focusing on the big compound lifts. I have a 10K race on May 11, and a sprint distance triathlon on July 27 that I'm training for.

For this entire month, I have stayed at a constant 207.5 lbs +/- 0.5 lbs. I have been tracking other measurements like circumferences and body fat (using calibers and BIA scale), and it's apparent that I have gained strength, regained muscle mass, and improved my overall fitness. Running is still at a slow pace, but actually enjoyable now. My wearables estimate that my VO2 max is 37 ml/kg; they did show 33 ml/kg last month when I had the test, so they seem to be correlated.

I think the hardest part of the last month has been the sheer amount of work I've put in, only to watch the scale stay steady. I track my intake rigorously, weighing everything I can and using MyFitnessPal to track it all. How are people able to eat anything else? I couldn't add rice or grains to my diet even if I wanted to, I would easily hit 2500+ kcal per day.

People eat that much? Or rather, burn that much? I burn 2000 kcal per rest day, and maybe 2800-3200 kcal on workout days.

I will stick with this, since it is working to improve my health and fitness. It would just be nice to see the scale move without having to fast for multiple days. Cursed slow metabolism.

How's your light environment/sunlight exposure? What's your waking body temperature (under arm for 10 minutes)? Have you had a thyroid panel done? (TSH, Free T3, Free T4, Reverse T3)

I’m in Toronto, so sun exposure is only improving now. We did Mexico in March, and Miami last week, and both were _amazing_ for mood and health.

I’ve never measured body temperature. I’ll check tomorrow.

Blood work in February came back fine for everything, including thyroid, except lipids and slightly elevated alanine aminotransferase.

Nice. Mexico and Miami are great for the sun. Catch at least 20m at sunrise and sunset (sunrise is most important). Also midday sun for as much as you can tolerate without burning and your schedule allows. As much skin exposed as possible and never with sunglasses.

Your waking body temperature should be around >= 97.8 and raise to 98.6 or higher by midday. Low waking body temperature can be indicative of low thyroid function even with normal labs.

TSH range is too high, you want it under 2. T4 is converted to either T3 or rT3. You want the majority going to T3. So if you have low normal T3 and high normal rT3, your thyroid is not working well. Low T4 means less to convert to T3.

You aren't cursed with a slow metabolism, you have just been having too many calories. If you are truly never hungry but still not losing weight, then why not reduce your calories by 200-300 a day?

I’ve thought the same, but then my food intake would truly be just plain chicken breast, fish, protein shakes, and green veggies. Which is basically what it is now, but I’d have to cut out the Greek yogurt, berries, and handful of nuts, and maybe the eggs. Remember, I weigh everything.

I can find the calories to cut, it just makes it difficult to sustain for longer than 2 weeks due to the mental load. Plus, I would bet my lifts in the gym would suffer after a while too.

Frankly, it’s probably easier to just go for an extra 20 minutes run.

Muscles are heavier than fat which makes weight an unreliable indicator for progress.

In terms of where carbs fit in, you're eating 200g of protein a day, which at a guess is 2x to 4x your lean body mass in kg. I'm not saying that it's wrong, it's probably very effective, but the average diet probably swaps that (historically very expensive) protein out for (historically very cheap) bread and rice.

Which we now know is suboptimal. Humans need more protein than we’ve been eating on the SAD. This is especially true as you age and you start losing muscle mass.

I aim for 1g per lbs of weight. There’s so many numbers out there for what’s the right amount, based on lean mass vs total mass, so I figure my number is close enough.