Hacker News Reader

Comment by Almaviva | Hacker News Reader

The facts of that study brushed aside: the participants diet was based on potatoes, rutabagas, turnips, bread and macaroni. Notice, not enough protein to maintain lean body mass. This is a bad idea.

Also, over 24 weeks the group lost 25% of their body mass.

Look at pictures of the participants: http://www.bbc.com/news/magazine-25782294 These look like frail bodys that, indeed, can sustain on 1600 calories per day, which explains slowed weight loss.

If you're an individual looking at how to seriously lose fat and recompose your body, don't look at popular media, but look at those with vested interest in effective results. E.g. athletic trainers in sports where weight management is a key point of the sport, like bodybuilding, wrestling, MMA, powerlifting. The science is quite clear, you just have to figure out how to filter out popular articles. (Lyle McDonald's site is a great start.)

Calorie restriction, with adequate protein intake, works. Also, any diet or lifestyle change that works creates a caloric deficit, and will also work if you count this deficit.

View on HN

Actually it's a huge mistake for amateurs to try to follow top athletes' training routine or diet. They have a different starting position, capabilities, and completely different goals. One thing that non-obese people just can't seem to understand when discussing diets is that it's not the same to loose a few pounds before summer and to spend 3-4 years dieting and changing your deeply hard-coded lifestyle in order to loose half of your weight or more. With obese people right mindset and self-discipline plays a huge rule, that's where most people fail. It's extremely hard and demanding to follow the strict behavioral rules for years and it's much bigger problem than just counting calories.

An even bigger problem is that obese people don't understand what will get them thin because conventional wisdom is a poor approach.

Cut way back on fructose, eat way more fiber, fat, and protein. That alone is huge. Want to go faster? Cut down artificial sweeteners and drink water (or something unsweetened). Want to go even faster? Do intense workouts twice a week. You don't have to run, don't have to spend a long time, but you do need to exhaust your major muscle groups. Then your body has no choice but to recharge and heal your muscles, which it will do by mobilizing fat.

An obese person following this can lose 5 pounds per week and not be hungry, although the craving for sugar in the first week or two will be akin to fighting a genuine addiction.

The overwhelming body of evidence suggests that sugar-free sweeteners absolutely don't cause fat gain, and that increasing water consumption has no affect on fat loss. Your body has a well regulated mechanism of telling you when you need water; it's called thirst.

Your advice on cutting back on fructose and eating more fibre fat and protein, without mentioning that you have to also be in a caloric deficit is a huge oversight. If my maintenance caloric intake is 2k cals per day and I change the macronutrient ratio I'm consuming but not the overall calories, I likely won't experience any weight loss except a small amount from thermic effect of feeding related to protein consumption.

You absolutely need to be in a caloric deficit to lose weight, and fructose is satan in disguise that's going to mess up your weight loss goals.

I wasn't implying drinking more water to help weight loss, just to avoid drinking things that have fructose.

The thing is, less fructose, more fat, fiber and protein will put someone in a caloric deficit without them trying. You crave sugar, but once you get over that you aren't hungry.

Remember that it isn't calories in calories out, it is calories absorbed calories out.

A caloric deficit happens naturally which is why it is so effective.

Everything you just said is absurd.

> The thing is, less fructose, more fat, fiber and protein will put someone in a caloric deficit without them trying.

Silly to assume this would be true for all individuals and a broad statement.

> Remember that it isn't calories in calories out, it is calories absorbed calories out.

All digestible material will be 'absorbed'. If your body couldn't digest food fully you would literally shit out chunks of undigested material, unless you have some kind of condition that doesn't happen.

> A caloric deficit happens naturally which is why it is so effective.

I'm not even sure that this means. If caloric deficits happened naturally we would all slowly starve to death.

It's generally not hard to lose significant weight while obese, keeping it off is long term is far harder.

If by following you mean eating exactly the same amounts then yes it would obviously be silly.

But you can follow someones diet by taking the core concepts; higher protein intake, moderate caloric deficit, increased activity, and make fantastic results after you tailor it to your individual needs by figuring out your caloric maintenance (by tracking food and being weight stable over a period of time not by punching your age and height into a calculator)

My wife has been failing to lose weight for several months, she is literally weighing everything she eats and recording calories (~1200/day), plus doing a several hours of quite intense exercise (stairs, etc) per week yet has hit a plateau for well over a month - any advice, things to read? (Note: she "can't" do low carb, which I personally recommend.)

If you've ruled out what is (imo) likely to be the most effective method, I'm not sure what results you expect. As gp suggested, you all should start with McDonald's book _The Ketogenic Diet_. I'm not saying it's gospel, but it's a start and it's one of the diets used by strength sports to control weight. There's lots and lots of arguing over this, but it's hard to dispute that many athletes use the ketogenic or similar diets to lose anywhere from 10 to 30 lbs of fat relatively quickly.

http://www.bodyrecomposition.com/the-ketogenic-diet/

I watched a documentary that talked about the Minnesota experiment and plateaus were also common despite the fact that participants were being fed insufficient calories. They had weird issues with their bodies like edema in their feet. Eventually, they found out that having a large meal occasionally would cause them to break through the plateau for reasons I forget.

Can you answer a) what 'can't' means quoted, b) current body fat (or at least where she is on the graph), and c) whether you have a decent set of scales (which will answer b).

With (a) -- the 'slow carb' thing popularised by Tim Ferris in The Four Hour Body was easy to stick to, had some good science behind it, and most importantly was clearly successful for many people.

With (b) -- there's an effective asymptote which makes it hard to shift the 'last bit' - though it sounds like she's not at that point.

With (c) -- without an accurate measure of body fat & muscle percentages it's basically blowing in the wind as you experiment with changes in your diet. And, lots of exercise - building muscle - will add more mass over the same volume of fat, of course. While carefully weighing food may work for some people, I think if it's not working after several months then you are obliged to accept it doesn't work in this case.

Has she consulted a GP? It's possible there's a metabolic problem (statistically unlikely, but possible).

For "can't", I think it's too emotionally draining for her, which is often followed by physical manifestations of pain. It seems to be a tough diet if you don't have the right mindset. I'll look into the "slow carb" thing though.

She hasn't consulted a GP, I highly doubt it's any sort of a metabolic anomaly, beyond just that which comes from aging.

Okay.

Personally I'd find it hugely more draining to be tracking and worrying about volume / mass of every bit of food I ate.

4HB - go buy / borrow a copy, and read the first fifth or so (that's the bit about diet and weight management - there may be some useful stuff regarding exercise in the latter sections for your wife, by the sounds of it).

Basics are: drink more water, reduce your salt intake, cut out starch (the 'avoid anything white' rule of thumb), eat much more (seriously) food to compensate for lack of starch / carbohydrates - often up to three times the mass of what you'd be eating previously, eat (lots of!) beans - they have some carbohydrate component, but often locked up or less digestible, and they're a cheap, nutritious, environmentally-friendly versatile food, monitor your weight very carefully, don't fret about fat (but watch out for fatty foods that contain lots of salt), have a high protein breakfast early, say with 30-60m of waking, and one day a week eat however much you like of whatever you like at lunch & dinner. That last thing is what makes it a particularly palatable (ha ha) and sustainable diet for many people.

To be candid I've never felt any aspect of it was especially tough - there's the social outings that may complicate things, but that's the same problem for anyone considering what they eat.

Good luck. : )

Disclaimer: I am not a doctor, nor a dietician. I am the type of person who finds it easy to gain weight or lose weight if I put my mind to it. Interestingly, I have helped friends lose weight by doing what I do. Y(W)MMV.

Depending on the size of your wife, I think that 1200 calories per day is too low. In fact, when I have crunched the numbers with nutritional software (http://nut.sourceforge.net/ absolutely worst UI in the history of the universe, but otherwise excellent), it is really, really difficult to balance nutrition on less than about 1600 calories a day. Potentially, you could do it with supplements, but eating a realistic diet that you can maintain is very important for improving your lifestyle (in my opinion).

My advice is to up the calorie intake in order to improve nutrition and correspondingly up exercise levels. You say she has several hours of exercise per week. I assume that means that she is exercising a few times a week. It would be much better to exercise 6 days a week (taking one day off for rest).

Intensity of exercise is important. If the intensity is too high, you will run out of sugar. If your goal is long term energy expenditure, then lower intensity for longer times is much, much better. Unfortunately, I don't have time to find you some links, but do a google search for graphs of percentage of sugar vs fat against exercise time.

It depends on the person (especially how fit you are already), but essentially the body starts out burning sugar and slowly starts using fat in preference. Generally speaking it takes about 30 minutes before you are burning 50:50. So if you do 15 minutes of intense exercise - to the point where you can't continue any more - you will have depleted your sugar resources. This impairs your body's ability to power itself for the rest of the day. Much better is to lower the intensity so that you can do 30-60 minutes of activity. This will spare the sugar in your body, while burning calories (from fat). Also, fat has nearly a 4:1 energy density advantage over sugar so you should find that the exercise is more enjoyable and your performance is much higher. In fact, a good 20 minute warmup to get the blood flowing and the muscles working, followed by a good workout will do wonders for you.

The level of intensity is quite important (and is something that I personally have difficulty with because I always train too hard). For the past 10 years or so, I've been doing cycling. At first I was riding hard for about an hour every day, to the point where I collapse at the end of the ride. My wife wanted to ride with me, so 3 or 4 days a week, I had to go at her pace. We still did an hour a day, but at a really slow pace. After a month or two, I could not believe the difference in my performance. It just sky rocketted. There are many scholarly papers on the topic which you can search for, but the old advice of doing base miles seems to work extremely well (at least for me). The idea is to maintain a level of exertion where you are slightly out of breath (have to breathe through your mouth), but that you can have a conversation easily. As far as I can tell, it literally doesn't matter what exercise you do, as long as you keep to that rule.

Obviously, 6 hours of exercise a week is a lot and it is hard to organise your life around it. However, 6 days a week is much, much easier than 3 or 4 days a week because it forces you to not be flexible with it. You must plan for it and make sacrifices. In my experience (you might be different), trying to add exercise (or anything else) to your life while avoiding impact to your life just means that you will be inconsistent. Take the hit up front and make it a priority. After that things just get easier. The other way around just stays difficult for ever.

Another important thing is to pick something that you enjoy. I used to run and if I took too much time off, I would always find that the first 2 weeks of getting back to it were hellish. After that, I would fall in love with it again, so sometimes you just need to persevere even if you don't think you are enjoying it. However, with cycling, it doesn't matter how long I've been away, I love it from the first down stroke of the pedal. If you don't enjoy what you are doing, keep searching for something that you do enjoy. It's going to be a big part of your life.

The number of calories you burn depends greatly on the sport you do, but I think a good rule of thumb is that you will be burning about 5-600 calories per hour. My wife just handed me one of those 1/3 sized cans of Pringles chips. There are 61 grams of chips in the can comprising 316 calories. I can easily eat this can of chips without even remembering I did so (wiping out half of my hour of exercise). If you always look at labels and think 100 calories is 10 minutes of exercise, it hits home. In fact, go to a Seven Eleven and look at the labels on things. Can you even buy a snack that has less than 100 calories?

As for food composition, I'm afraid to say that I think people are over-optimising on the wrong thing. Whether or not low carb is effective, I don't know, but none of the people who have followed my advice has ever failed to lose whatever weight they wanted (see disclaimer below!). If you must obsess with what you are eating, I would err on the side of reducing fat. Again, the calorie density thing means that if I'm eating lower fat, I get to eat more volume. For exercise, I firmly believe in sparing sugar, and I can't imagine any low carb diet would perform well for endurance sports.

One last piece of advice: don't try to lose weight too fast. Absolute max in my opinion is about 1 kg per week (about 2 pounds). Honestly, I would dial that back to 500 grams per week because it just seems healthier from my experience. If you do this for only 1 year, you will lose between 25-50 kg. That is a crazy amount of weight (and you will already have a lot of loose skin that won't rebound in that amount of time!). If you think, "I don't want to wait a year", then my experience is that you will fail anyway. It's not about the goal, it's about the journey. Without experiencing that journey, the goal will disappear. Find a way to enjoy it -- it's the only way.

One more disclaimer: if you need to lose more than 20-50kg, don't follow my advice. Seek a professional and get qualified advice. Random people on the internet are not qualified to help you (myself included).

Many thanks for the detailed post, I will try to pass this on to her, although she tends to not be terribly open minded about discussing diet, so it's a bit difficult but will do my best.

The whole thing about diet and exercise is it's a tough subject, because it's not completely understood, and the same thing doesn't work for everyone. Also, fitting in a 1 hour workout 6 days a week (plus typically a commute to & from gym, showering) on top of work, commuting, and family, is not easy.

Most of what you said seems logical, but this part seems a bit iffy to me: "Much better is to lower the intensity so that you can do 30-60 minutes of activity. This will spare the sugar in your body, while burning calories (from fat)." I mean, it's not a crazy idea, but it doesn't seem particularly logical to me either. Maybe it's scientifically well documented though, I have no idea. That's why personally I prefer going the low carb route - it's a very simple theory that makes complete sense to me, and the results for most (if not all) people that follow it (and don't cheat like my wife did, then claiming that it "doesn't work" for her) are pretty spectacular. However, the ability to eat that strict diet varies largely per person - it was great for me because I tend to like that kind of food, but for others it is psychologically difficult to maintain and depression and self-pity become very big problems.

I think your advice that 1200 calories is too low is very interesting, because she has been very strict at that level + exercise, so it seems apparent that her body has gone into some sort of an ultra-efficiency mode. (She's tried cheat days but with no effect....maybe there's a particular food she's eating that's a problem.) I hit the same wall on keto where I just couldn't lose anymore despite caloric restriction, but luckily I had already hit my goal weight by then.

Lots to think about, thanks for the advice!

Body adapts quite well to most changes. Probably the exercises have become easier to do for her. You can try mixing it up or try https://en.wikipedia.org/wiki/High-intensity_interval_traini...

HIIT goes against the advise above (low intensity, longer duration to burn fat) but it does work for some

High intensity is suggested here also:

https://www.youtube.com/watch?v=QHHzie6XRGk

So confusing, what's right!!??

There are some definite possible advantages to HIIT. If you are careful to monitor your heart rate to keep a good level overall, then I think it has good potential. I used to run track when I was young (400 and 1500 meters) and we always trained this way.

Honestly, if you are training every day and being relatively careful with your diet, then you will pretty easily get down to a weight that the average North American would call "skinny". The main problems I've seen with people are not understanding what they are eating (Google tells me a single blueberry muffin is 377 calories -- that's practically a meal in itself!!!) or people who are fooling themselves about their exercise (unless you are a competitive athlete, the 5-600 calories per hour is about right -- if you are lifting weights, you can divide that by a fair amount).

Diet and exercise is actually very well understood, and the same thing will 'work' for everybody.

There just happens to be a lot of bullshit floating around.

For example your claim about the size of your wife's deficit... unless you tracked eveyr calorie she ate and she remained weight stable for weeks for you to get an average intake: you have no idea what her maintenance intake is and thus no idea how big of a deficit she is in. Caloric requirement calculators are bullshit, there's too much individual variation.

As for losing weight; it's pretty simple. Resistance train a few times a week, to maintain muscle mass, consume around 0.8-1g of protein per lb of LEAN mass, and be in a moderate deficit of a hundred or so calories, and continue to make adjustments my lowering food intake and/or increasing activity to keep the fat loss moving as your caloric maintenance changes to your lower body mass.

just an aside, there is no 'ultra efficiency mode' you comment here:

>I just couldn't lose anymore despite caloric restriction

is completely bogus, unless you're suggesting your body violates the law of conservation of energy

> Diet and exercise is actually very well understood, and the same thing will 'work' for everybody.

> just an aside, there is no 'ultra efficiency mode' you comment here:

Do you genuinely believe that metabolism doesn't vary across individuals, or for an individual over time? Do you think the bodies of all individuals have precisely the same ability to both absorb calories from ingested food, as well as produce motion with the exact same efficiency? Do you believe enzymes present in the digestive system have absolutely no effect whatsoever on the calories in / calories out calculations? Do you think every calorie you put into your body is converted into energy?

1 kg of fat is about 7700 calories. So if you are in deficit by 1100 calories per day, then you should lose about 1 kg of fat. Assuming that you have a base metabolism of 2000 calories per day (average for a male of average size), and say you did an hour of moderate aerobic exercise (like jogging) every day (600 calories per day), the with a diet of 1500 calories, you should find yourself losing about 1kg a week on average.

If you are not losing any weight with the above, then the potential explanations are:

- You are in ultra efficiency mode: In other words, you are burning only 900 calories a day.

- You are not running an hour a day.

- You are not eating 1500 calories a day.

Let's say you are 70 kg. It takes 1 calorie of energy to raise 1 kg of water by 1 degree. You are roughly 15 degrees above ambient temperature. Thus it takes 1050 calories to raise your temperature from ambient to body temperature. It is highly unlikely that your body will be able to maintain body temperature for an entire day on 900 calories.

Thus, the only other explanation are the other two.

Do you genuinely believe that metabolism doesn't vary across individuals, or for an individual over time?

It differs a bit. Therefore, the problem is to find out a particular individual's calorie requirements, which is achieved by carefully tracking calories and weight. I.e. if the weight is stable, we found this person's calorie requirements.

Do you think the bodies of all individuals have precisely the same ability to both absorb calories from ingested food, as well as produce motion with the exact same efficiency?

For weight loss purposes it is not so important. There is a top limit on energy to be absorbed, i.e 9 cal from a gram of fat. If a person only absorbs 8, good for him, but there is no way he will absorb 10.

Do you believe enzymes present in the digestive system have absolutely no effect whatsoever on the calories in / calories out calculations?

Again, there is a hard limit on how many calories can be extracted from a unit of food.

Do you think every calorie you put into your body is converted into energy?

For the purpose of weight loss, not so important. You digest only half of what you put in your body - good news, you can eat more and still lose weight. You digest everything - also no big deal. It's just that you cannot magically eat 1g of fat and suddednly gain 100g bodyweight from it.

You did a fairly decent job of discrediting your "the same thing will 'work' for everybody" statement.

"top limit on energy to be absorbed" is one of those interesting statements that sounds like an answer and proof of something, but actually isn't relevant and is a dodge of the question I actually asked. Of course there's an upper limit to what calories can be absorbed from food, you can't consume that which literally isn't there - the question is, is is the caloric content that is actually extracted the same for all people (which is a subset of the question does the same thing work for everybody).

You did a fairly decent job of discrediting your "the same thing will 'work' for everybody" statement.

My "same thing works for everybody" is, in other words, "every person has a number of calories N, eating under which he will lose weight". I think I stayed pretty consistent. And yes, N may vary over time, but it still exists.

the question is, is is the caloric content that is actually extracted the same for all people

I can only restate that yes, it is different and no, it is not very important if our goal is weight loss.

Suppose I extract 1500 calories from a meal, and you 1800 calories from the same meal. But the "thing that works for everyone" remains: you track your calories and weight, I track mine, maybe my weight is stable at 2000 calories per day, yours at 1700 calories per day. Then we just respectively start lowering our intake until we reach the desired rate of weight loss. Algorithm remains the same, we just plug in our own numbers.

which is a subset of the question does the same thing work for everybody

No, I can't see relevance.

For lack of better example, all homes are different, some may have only rectangular rooms, some have oddly shaped rooms etc. So kind of "everyone is different". And still, anyone can easily calculate the space in square meters, or at least achieve a very close approximation for all practical purposes. So it does "work for everybody".

My argument is that the calories in (eaten) / calories out (exercise) explanation, and the idea it is just that simple and if you're not losing weight you're cheating on your diet or lying about your exercise is wrong.

You seem comfortable with the idea that different individuals have differences in caloric uptake (Suppose I extract 1500 calories from a meal, and you 1800 calories from the same meal), but I don't think others are comfortable with that idea. And if it varies across individuals, why is it impossible to vary with one individual over time, or change drastically in a short period of time? Can the physiology of your body change to (for example) start extracting more calories from food than it normally does? It doesn't seem like that crazy of an idea to me, and if it can do this (as anecdotal evidence suggests), then it makes weight loss strategies much more complicated, and it makes the simple calculations no longer work under all scenarios.

This doesn't seem like a terribly controversial idea to me.

You can't extract more calories from food than their are. Calories are measured by actually incinerating the food and measuring how much heat it gives off. That is literally how much energy there is. So if you eat 2000 calories of food energy, you can not (if you are obeying the laws of thermodynamics) gain more energy than that. You can only absorb less.

Similarly, as I said in a message above, there is a lower limit for how much energy your body must burn in order to maintain body temperature. You will find if you look at the rate at which corpses lose heat to ambient temperature that it is very, very close to what is listed on those base metabolic rate charts. Again, I have to stress this: you can not burn less than that without decreasing your temperature and dying. It is a physical impossibility.

There are obviously variations, of course, but they must (by physical necessity) be on the up side. So you can easily eat 3000 calories and not gain any fat, even though you don't exercise, if you have a thyroid problem, or if you have a digestive problem that causes food to shoot through you before you can process it.

On the other hand, you can not (due to the laws of physics) eat less than the number of calories required to maintain body temperature and not lose weight. This is conservation of energy. And as I said, the minimum amount of energy required to maintain your temperature is very close to those base metabolic rate charts.

Sure you can be off by 100 calories a day. You can't be off by 1000. It just isn't possible. So if you are in deficit for several hundred calories a day and you aren't losing weight it is necessarily because you have measured your exercise or diet incorrectly. As I stated several times, this usually occurs because companies outright lie about how many calories you can burn through exercise (and are often off by 1 or 2 binary orders of magnitude). It is also because people completely overlook high calorie foods, even if they are otherwise very careful.

> Similarly, as I said in a message above, there is a lower limit for how much energy your body must burn in order to maintain body temperature. You will find if you look at the rate at which corpses lose heat to ambient temperature that it is very, very close to what is listed on those base metabolic rate charts.

Do you happen to know a typical range for this? For caloric maintenance level, there is:

* Body temperature maintenance * Operating bodily functions (pumping blood, breathing, etc) * Basic "non-exercise" movements

For all of these, calories consumed (eaten) must take into consideration:

* caloric extraction (basically, net of calories remaining in excrement) * caloric consumption efficiency (of those retained, how efficiently are they converted into heat & kinetic energy)

There are actually two sets of numbers for the first three points: actual literal calories required, and then the set that takes into account the last two points. How different are these numbers? I wonder, assuming this "weight plateau" while still in what is thought to be caloric deficit is actually real, could the general understanding of the last two points not be correct in all situations?

As discussed, it seems some people extract more calories from the same food (for whatever reason), although how true is that? The other alternative is that they have similar bodily behavior as someone with a thyroid problem (calories are uptaken (I think?) but not stored as fat - not sure how this works then, are they excreted?), but if on a strict diet, the body could change causing a plateau.

I don't think I'm doing a very good job of explaining myself.

if you're not losing weight you're cheating on your diet or lying about your exercise

Not necessary lying. But I have read countless stories, where the TLDR; would be "I thought I was eating very little and very healthy but then I bought a kitchen scale and started weighing and logging everything and OMG was I wrong".

I was also sceptical about counting calories and never needed to do that and was at healthy weight. But recently started for some fitness reasons, and here's a personal anecdote for fun:

Greek salad is a very healthy meal, where olive oil, a very healthy oil, is used as a dressing. So I always just put "some" in it. With a scale, turned out that was 40g. That served 2 people, but still: almost 200 cal from just dressing from just one meal. Another thing I noticed was that olives and feta cheese were under 20% of the salad volume, but over 80% calories. So just by varying the amount of these I could bring the serving calorie content anywhere from ~100 cal (substituting olive oil with balsamic vinegar) to ~500 cal.

So I can see how people may honestly say "oh, but I eat nothing but salads and still can't lose".

why is it impossible to vary with one individual over time, or change drastically in a short period of time?

Because there is little to no evidence for that, and I'm talking about metabolic ward quality evidence.

Sure, if you're in calorie deficit, your metabolism will slow somewhat, but not drastically and not in a short period of time. Sure, some medication plays tricks with hormones that regulate hunger, but not so much with metabolism directly. I don't know about conditions where metabolism will drastically slow down in a short period of time. Even under water fasting it takes at least 72 hours of 0 calorie intake to notice a measurable change.

> Because there is little to no evidence for that, and I'm talking about metabolic ward quality evidence.

Do you happen to know (I don't) if "caloric uptake" specifically has been studied closely? Specifically:

* When you consume <x> calories, how many are extracted by the body and how many are excreted? * Can this vary by food type? * Can this vary across persons, and across time for the same person?

From personal experience I have witnessed what seems to be impossible, and my diet was so simplistic (sausage, bacon, spinach, multi-vitamins) that I couldn't have been making a mistake, yet I hit a plateau. The only logical explanation I can think of is a massive short term change in caloric extraction.

Do you happen to know (I don't) if "caloric uptake" specifically has been studied closely?

No - I also don't know. I haven't seen it mentioned, but I also haven't seen reports about the amount of calories absorbed by the body change for no reason at all. So I'm not completely discarding the possibility, but I would like to see some studies and at least an attempt of explaining what might cause it.

The only logical explanation I can think of is a massive short term change in caloric extraction.

I can come up with some more: 1. The water retention, or the so-called "woosh effect"

http://www.bodyrecomposition.com/fat-loss/of-whooshes-and-sq...

What’s going on? Back during my college days, one of my professors threw out the idea that after fat cells had been emptied of stored triglyceride, they would temporarily refill with water (glycerol attracts water, which might be part of the mechanism). So there would be no immediate change in size, body weight or appearance. Then, after some time frame, the water would get dropped, the fat cells would shrink. A weird way of looking at it might be that the fat loss suddenly becomes ‘apparent’.

Now this article is not rich with links to science, so take it with a grain of salt.

2. As you lose weight, your caloric requirements naturally go down. So to remain in deficit, you have, unfortunately, revise your targets down from time to time, otherwise you reach balance and stop losing.

3. Somewhat related is the decrease in NEAT - Non Exercise Activity Thermogenesis. In short, you tend to be less active when you are in caloric deficit, and may not consciously notice it. Sorry for the same source again, it happens that this guy writes a lot on the subject.

http://www.bodyrecomposition.com/fat-loss/the-energy-balance...

For example, say you put yourself through 500 calories of hard activity but, due to fatigue, you sit on the couch more later that night, burning 300 calories less than you expended before training. The supposed 500 calorie deficit you’re creating is really only 200 calories because your SPA/NEAT has adjusted itself. You might expect one pound per week fat loss but the deficit is actually less than half of that

The whole article is a very good summary on the mathematics of weight/fat loss.

> You did a fairly decent job of discrediting your "the same thing will 'work' for everybody" statement.

Did you even read his post? A caloric deficit will 'work' for everybody by definition.

A caloric deficit once achieved will work for everybody, but different people absorb calories differently - so, as was being discussed, the same thing (calories consumed per kg of body mass + exercise) will not work for everybody.

you keep harping on this 'absorbed calories' thing. and it's irrelevant to the discussion and not helping your argument. people have different caloric requirements doesn't mean that a some people magically can't turn body tissue into energy.

Nowhere did I state that metabolism doesn't vary across individuals.

On the contrary I think that individuals have vastly different caloric requirements.

None of this means that a caloric deficit and increased activity won't cause all individuals to lose weight, just that the absolute value will differ between individuals.

> None of this means that a caloric deficit and increased activity won't cause all individuals to lose weight, just that the absolute value will differ between individuals.

Do you accept that the caloric value may vary in one person due to changes in gut flora? Or changes in metabolism?

Maintenance caloric requirements change as your body mass changes (and composition). It's pretty obvious that, for example, your maintenance requirement at 200 lbs will be different from your maintenance requirement at 150 lbs; you have less tissue to sustain.

Any comments on the question asked? (Gut flora & metabolism)

Hopefully my previous answer will help you. Unless you can sustain nuclear reactions in your gut, you can't extract more energy from the food. It is not possible. You can easily extract less, though.

The calculations are simple because that's how they were designed to work. Going the other way (gaining weight) is actually where it is problematic (because not all of the food value is used -- although bodies are remarkably efficient).

The calorie value is an absolute upper bound. But some people have a gut flora that helps them extract more of those calories than the regular population. And some people have a gut flora that helps them not extract some of those calories.

And since gut flora can change over time a person eating 2000 might be maintaining weight one year but gaining weight the next year with no change in food intake.

I agree that people who say "I eat very little and I'm not losing weight" are mistaken.

> And since gut flora can change over time a person eating 2000 might be maintaining weight one year but gaining weight the next year with no change in food intake.

Finally a voice of reason.

Do you happen to know of any decent literature or particular keywords one might google to read up on this?

> Nowhere did I state that metabolism doesn't vary across individuals.

"the same thing will 'work' for everybody."

"just an aside, there is no 'ultra efficiency mode' you comment here: >I just couldn't lose anymore despite caloric restriction is completely bogus, unless you're suggesting your body violates the law of conservation of energy"

If metabolism can vary by individual, why is it impossible for the metabolism for one individual to change over time? Serious question, I honestly don't know.

I just wanted to say that I generally agree with the above (was unsure whether to reply to the parent post or this one). My only real quibble is that I think the protein requirement is too high (even of lean mass). Possibly I'm a special case, but 0.6g per lb of lean mass has been enough for me to gain muscle.

The "ultra efficiency mode" is definitely one of the more unfortunate things to come out of the low carb camp, IMHO. generally speaking, unless you have a disease or physical disorder (like hyper thyroid) you are going to be burning/eliminating about 1400 - 2500 calories a day. It can be quite a bit higher for some diseases or disorders where you can't process food.

Running is a great exercise for counting calories because it expends a pretty predictable 80-110 calories per mile (depending on pace). Other exercises can be extremely variable (to the point where I have seen people overestimate the calories by factors of 3-5). Do not trust exercise machines for caloric output. Every single one I've seen is off by at least 50% (they flatter you so that you demand their machine).

But generally speaking, if you do aerobic exercise continually for 1 hour, you will burn 5-600 calories. If you eat 1600 calories, then you will have a balance of about 1000 calories, which will certainly be in deficit for the average person (if you are really small, then it might not be, but I suspect it will be even then).

So why do people hit plateaus?

- They vastly overestimate the calories burned from exercise.

- They vastly underestimate the calories eaten.

Mostly it is the latter. It is not hard at all to put 100 calories of butter on a slice of bread. It is dramatically easy to put 200 calories of salad dressing on a salad. It is easy to say, "I only had a muffin and a coffee for breakfast" without realizing that said muffin (with butter) and coffee (with cream and sugar) could easily be in the 500 calorie range. My friend used to go to subway for lunch and have a 6" salami sandwich, one of those small bags of chips, and a sweetened iced tea for lunch. He had no idea he was pushing 1000 calories for lunch (the muffin and coffee for breakfast, 6 inch subway sub for lunch and... sorry... maybe you can have half an apple for dinner).

So, it is quite easy to loose weight when you are 220 lbs and burning 2500 calories a day. But then when you get down to 170 lbs and are burning 1900 calories a day, suddenly that miscalculation for how much exercise you are doing, or the 300 extra calories you are eating, but didn't realize makes a massive difference. Similarly, if you have health issues (especially digestion) that cause you to eliminate food rather than digest it when you are heavier, it can make a dramatic difference later if you get healthier and start actually processing this food.

The overestimation of exercise is a bad one because it is often fuelled by industry lies. Go to a gym and someone will tell you that you are burning 1000 calories an hour lifting weights, or that adding a kg of muscle will increase your metabolism by 100 calories a day or some other such nonsense. My brother (who is otherwise a very intelligent person) once thought that he could burn 1600 calories an hour on a bicycle (possibly if he is in the Tour de France, but pushing 150 watts is more than most beginners can handle for an hour and results in 540 calories an hour). Stuff like that makes me fairly angry...

> The "ultra efficiency mode" is definitely one of the more unfortunate things to come out of the low carb camp, IMHO. generally speaking, unless you have a disease or physical disorder (like hyper thyroid) you are going to be burning/eliminating about 1400 - 2500 calories a day. It can be quite a bit higher for some diseases or disorders where you can't process food.

Do you know of any particular studies debunking the theory that resting metabolic rate does not and cannot change in an individual? Honest question, I don't know for certain - I "believe" it can and does, but my belief is based on anecdotal observation and logic.

You're conflating two different ideas. The idea that metabolic rate can't change for an individual (which it obviously can as it's based on that persons body mass, lean mass, age, etc [all of which can change] along with genetics) with the concept that there is a magical starvation mode wherein further reductions in calories won't produce any loss in weight (which is obviously false as people starve to death worldwide all the time).

Actually we are talking about a plateau despite maintaining an apparent deficit from an orally consumed calories perspective. Why does this plateau happen? Please don't be disingenuous and claim I am implying magic and that you can live without food, you know that isn't true.

> Why does this plateau happen?

If you're asking why weight loss slows down in a diet the answer should be pretty obvious. You continue to lower calories to keep yourself in a deficit, at a certain point your calories become very low and people have trouble with compliance.

Either that or the body enters a special high efficiency mode where it becomes a super efficient energy conservation machine all of a sudden?

The simplest solution is probably the correct one.

Bullshit. This is 100% bullshit. If she is on ~1200/day she would be losing weight. That is how physics works. My advice is stop lying or tell your wife to stop lying.

You would think so, but the "weight loss = calories in - calories out" is far too simplistic to describe the real world.

No. It is exactly how to describe it. Energy in vs energy out.

It ignores metabolism, there is evidence that the presence (or lack of) certain enzymes in the digestive system can drastically affect ability to absorb calories, etc.

It is too simplistic to explain reality.

It really is not.

Just for fun, I'll paste my reply to another comment here:

I'll add an extra one for you: in controlled lab tests, would all subjects lose weight precisely as predicted by a formula that considered their diet and physical activity?

in controlled lab tests, would all subjects lose weight precisely as predicted by a formula that considered their diet and physical activity

http://examine.com/faq/what-should-i-eat-for-weight-loss/

This page has links to 20 controlled studies, and the calories in - calories out hold. It is when people are allowed to self report, the problems begin.

Sure, everyone's caloric requirements are different, but everyone will lose weight if in caloric deficit. It is just the question of figuring out what will be deficit for this particular person.

Do you need a subscription to read the full articles? For one thing, I'd like to read how they are measuring "energy in", are they subtracting calories in the subject's excrement?

Some articles are open access. In one case, for example, they used bomb calorimetry:

Bomb calorimetry performed on eight batches ofsimilar formula prepared in the research kitchen of the Rockefeller University Hospital between April 1988 and July 1990 had a coefficient of variation for Id/g of 1 .9%.

http://ajcn.nutrition.org/content/55/2/350.long

Again, I've seen little evidence of excreting unprocessed calories being a common case. And if we're looking at weight loss anyway, excreting some calories would even be an advantage.

It is true that there are many factors that affect how a calorie is digested and stored, it is a complex system.

But it is also true that there is no other source of energy for the body than mass. There is no metabolic process that can produce energy for more than a few seconds without a reaction that consumes mass (the carbon in said mass being breathed out as CO2).

Are you 100% certain your wife is only consuming ~1200/cals a day?

Many people drink a lot of calories per day (could be soda, fruit juice or alcohol) without realizing it, and many people sneak small items and lie about it too.

Aside from that, based on your wife's age, weight and height, what's her recommended stable calorie intake per day? I would recommend only going a few hundred below that to lose weight, as other comments have said, the body can react very strangely if you restrict too much - it thinks it's starving.

> Many people drink a lot of calories per day (could be soda, fruit juice or alcohol) without realizing it, and many people sneak small items and lie about it too.

She's been guilty of cheating in the past, but I'm quite sure she's not this time. Her trainer says target 1400 calories but she's been doing 1200, which seems reasonable to me, but maybe that's too low and kicking the body into self-preservation mode.

> Her trainer says target 1400 calories

That sounds very low. Can you please tell me what this says based on her stats?

http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-he...

(I'm not saying that calculator is a good one or anything, I'm just curious if it says anything near 1400)

I will check. Just ran it for myself and it told me 2000 calories, waaaaay more than I would have expected.

Yeah, it seemed really high for me (2800) too. I've always figured at my current weight I'm closer to 2500 to maintain.

There is no starvation mode that makes the body disobey the laws of conservation of energy. Sorry. Your wife is either not in a deficit due to the calories not being low enough (or not exercising enough) or she's simply eating more and not recording it.

Do you believe it is literally as simple as calories in calories out, for all people equally?

The analogy is to a gas tank in a car.

If you put in 5 gallons per day, but only use 4 gallons per day, there is an extra gallon building up each day, and it will be stored somewhere (fat in the body). Some bodies will be more inclined to store this than others, and store it in different places.

If you put in 3 gallons per day, and burn 4 gallons per day, there is a deficit, and the extra will be burned from stored reserves (stored fat). It must, otherwise the machine would be incapable of traveling the distance that 4 gallons requires, and would not function. When that runs out, you die (i.e. starving to death).

Yes, it factually has to be that simple, for all creatures, there is no possible other way. It is extremely simple science and logic.

Notice I said simple, NOT easy. They are two different things.

Also note that for all people the speed at which your body adjusts to eating less than you burn will be different, as will exactly how your body responds to your eating less than you burn. For example, if you seriously under eat calories, it's widely accepted your body will think it's starving to death, and will conserve energy it normally would not - i.e, you'll be cold, your immune system will be weaker, your digestion will not be optimal, your hair and skin will deteriorate and not be replenished well etc. etc. So even though you're eating less than you were burning last week/month, you might not lose (much/any) weight because your body has quickly adapted and changed the amount of calories required as best as it can by shutting down, or minimizing non-critical functions. You could imagine an intelligent car doing the same thing when it realizes it isn't being fed enough energy for the demands being put on it - it might turn off the air conditioning, lower itself, jack up the tire pressures, fold in rear view mirrors and limit itself to a top speed of 30mpg all in the name of more efficiency.

Source: I got involved with Weight Watchers years back - have personally been involved with literally thousands of people losing tens of thousands of pounds combined. WW is by very definition eat less energy than you burn. (well, the new formula gives a little bonus if you eat lots of fiber and another if you eat very little fat, but it hardly makes a difference)

Me: Do you believe it is literally as simple as calories in calories out, for all people equally?

You: Yes, it factually has to be that simple, for all creatures, there is no possible other way. It is extremely simple science and logic.

And then you proceed to point out several items (that I agree with) showing that calories in / calories out doesn't fully describe the complexity.

In your "If you put in 3 gallons per day, and burn 4 gallons per day" analogy, the devil is encapsulated within "burn", in that the fuel efficiency of the car can vary - therefore while the energy going in is a constant, the energy being burned will vary. And additionally when dealing with humans, ability to absorb energy from fuel in also varies (many calories come out as waste, how many varies by individual.)

> then you proceed to point out several items (that I agree with) showing that calories in / calories out doesn't fully describe the complexity.

That's because for 99.999% of people to lose weight, they don't need to understand / deal with anything more complex than calories in / calories out.

When your grandma wants to use a computer, she doesn't need to understand interrupts and CPU instruction sets anymore than a 3 year old needs to understand HTTP and TCP/IP to surf the web.

It really is this simple. Figure out how many calories you should be eating daily to maintain based on your height, weight, age, sex and activity level. (And let's be perfectly honest here, for anyone that's obese or higher, it's an ungodly amount of calories per day - so many that it would be very difficult for anyone to eat that many calories per day without eating massive amounts of fat (fried food) and sugar (soda). So cut out just soda for most people and that's enough)

Eat 200-300 less than that per day, for 3 months, and do a tiny bit more exercise than you normally do - and by tiny bit for someone that does nothing, that means walk an extra hundred yards to your car daily, nothing more. No running on the treadmill, no caring about carbs vs. fat vs. protein. Hell, if you stay 200-300 under what you require, it doesn't even matter if you still eat fast food like you used to.

After 3 months if you have not lost weight, cut down another 200-300 per day, and continue for another 3 months.

Repeat.

You will lose weight, it can not be any other way, and the "complexities" mentioned above need not be considered, because they over complicate the issue.

thank you. said it better than I would've

I have trouble reconciling this with my personal experiences - I did keto for several months and lost about 25 pound until I hit a plateau that I couldn't get past after trying for over two weeks, eating the same diet as before, and I know with certainty I was WELL below my maintenance caloric intake.

> You will lose weight, it can not be any other way

I wonder if maybe the logical impossibility people are having trouble with is maybe from not differentiating between calories consumed and calories absorbed?

> I hit a plateau that I couldn't get past after trying for over two weeks

2 weeks? 2 weeks?

We're talking about changing your eating and exercise habbits for the rest of your life. Two weeks is such a tiny drop in the bucket it's hard to even measure it, and likely too many things were in flux to have settled down.

Continue for 3 months. You will lose weight.

> I wonder if maybe the logical impossibility people are having trouble with is maybe from not differentiating between calories consumed and calories absorbed?

It makes no difference, because you can't absorb more than you ate. Don't think about how much your body is absorbing, because it's too hard to measure and do anything about. Think and focus on the thing you can impact - how much you eat.

You are worrying about what kind of efficiency your car is getting, when all you need to care about is to stop putting so much damn gas in every day because the tank keeps overflowing.

When the tank is overflowing each and every day, put in less gas!!!!

> We're talking about changing your eating and exercise habbits for the rest of your life. Two weeks is such a tiny drop in the bucket it's hard to even measure it, and likely too many things were in flux to have settled down.

I had already hit my target so didn't mind quitting. The interesting part of the conversation to me is the plateau itself - according to many people, all people and especially individuals are the same, calories in minus exercise equals weight gained (or lost), there is no such thing as flux, every day is exactly the same, literally the only variable is your weight, and that hardly changes at all day to day. Yet, myself and millions of other people do in fact hit a plateau with no noteworthy change in diet or exercise. I'm just having a bit of fun seeing the variety of ways people twist logic and dance around questions related to this phenomenon while still maintaining this hardline calories in calories out stance. :)

> It makes no difference, because you can't absorb more than you ate.

Correct. However, you can absorb less than you eat! Eat 2000 calories, absorb 1500, poop out the rest, gee, I wonder if that might have any effect on weight loss?

> The interesting part of the conversation to me is the plateau itself - according to many people, all people and especially individuals are the same, calories in minus exercise equals weight gained (or lost), there is no such thing as flux, every day is exactly the same, literally the only variable is your weight, and that hardly changes at all day to day.

I've never seen anyone claim that calories in / calories out will have an immediate impact and should be visible on the scales within days. On any given day your body might hold onto lots of water, so you don't lose weight. Later you might get really dehydrated on a hot day, so you appear to have lost weight, etc. etc. Times one million variations for why you won't see "results" "instantly".

Don't for one second think that any of this is measured on the scale of days, or weeks. You are completely deluding yourself if you think it is.

A scale of months hardly makes sense either. Do everything for a minimum of 3 months before you expect to see a difference, on the scales or in the mirror. Everything takes time, and you're in this for the rest of your life, so what's the difference anyway.

> Correct. However, you can absorb less than you eat! Eat 2000 calories, absorb 1500, poop out the rest, gee, I wonder if that might have any effect on weight loss?

It won't, because that's how your body has been functioning for a long time.

If you're trying to lose weight, you just have to feed it less, who cares how much it's extracting, it's completely irrelevant.

Like I said, it doesn't matter if you're in a car that gets 30mpg or one that gets 50mpg, as long as you put less gas in the tank than you are using, sooner or later the tank will run out!

Stop trying to make this harder than it needs to be, or more complicated that it needs to be.

Consume less calories than you burn, and in the long run you will lose weight.

> Like I said, it doesn't matter if you're in a car that gets 30mpg or one that gets 50mpg

But what if the car adjusts its fuel efficiency dynamically? If that's the case, it might be something worth investigating and understanding, no?

> Stop trying to make this harder than it needs to be, or more complicated that it needs to be. Consume less calories than you burn, and in the long run you will lose weight.

Correct, but if certain levels of caloric deficit can cause physiological changes that affect rate of weight loss, altering the difficulty of losing weight, why be opposed to discussing that idea? Why not maximize efficiency of weight loss?

> But what if the car adjusts its fuel efficiency dynamically?

And your body does just that. That's why you continually re-evaluate what your calorie needs are and adjust your intake accordingly. Weight Watchers does this every single week. See how much you weigh, figure out what your "maintenance" calories are, and make sure you eat 200-300 less than that.

Then, yes, your body changes, adapts and becomes more efficient, because you're changing things, and it's getting lighter so be definition it needs less calories. So then check-in again a week later repeat. And repeat. And repeat.

> If certain levels of caloric deficit can cause physiological changes that affect rate of weight loss

I wouldn't go there. I mean, if you want to change the rate of weight loss, just eat absolutely zero calories for 6 months. I grantee you'll lose a massive amount of weight. Is that a good idea? absolutely not. There is an amount that's sensible and works well. It's something like 200-300 less calories than your maintenance requires.

> * Why not maximize efficiency of weight loss*

It's interesting to me you're still viewing this as "weight loss", and something to be maximized and made more efficient, and something with an end date. What hasn't dawned on you yet (and usually takes most weight watchers people a very long time to get) is that, at some point in the future, you will weigh your goal weight. When you get there, your calorie requirements to maintain that are going to be massively lower than they are now. Actually, they're going to be right around what you were eating the week before you got to your goal weight. Guess what? That's now what you're going to eat for the rest of your life.

You can't really maximize the efficiency of the rest of your life. So just start working towards it, today.

> Then, yes, your body changes, adapts and becomes more efficient, because you're changing things, and it's getting lighter so be definition it needs less calories.

This doesn't require any "adjustment" on the body's part, it is a natural outcome of having less mass to maintain. I am speaking of something different, of the possibility of the body sensing starvation and shifting into kind of a high efficiency sustainment mode, perhaps lower metabolism, perhaps more efficient extraction of calories from food. Does this actually happen, I don't know, but I believe from personal experience and reading forums that there is a phenomenon of hitting a weight plateau that is not explained by the simplistic calories in, calories out theory. I don't know why this idea seems so offensive to people.

> I wouldn't go there. I mean, if you want to change the rate of weight loss, just eat absolutely zero calories for 6 months. I grantee you'll lose a massive amount of weight.

Why do conversations on certain topics have to degrade to nonsense if someone doesn't agree with your point of view?

> It's interesting to me you're still viewing this as "weight loss", and something to be maximized and made more efficient

Some people, me for example, can diet for a period, drop <x> pounds, and then I'm good for years with paying very little attention to diet - not everyone has it that easy though. But while I am dieting, I prefer to optimize it so it's over as quickly as possible.

The idea of optimizing things is a fairly common theme on this site, but again, there seems to be something about the topic of dieting that changes the way people think.

> This doesn't require any "adjustment" on the body's part, it is a natural outcome of having less mass to maintain. I am speaking of something different, of the possibility of the body sensing starvation and shifting into kind of a high efficiency sustainment mode, perhaps lower metabolism, perhaps more efficient extraction of calories from food. Does this actually happen, I don't know, but I believe from personal experience and reading forums that there is a phenomenon of hitting a weight plateau that is not explained by the simplistic calories in, calories out theory.

I personally think that what you're describing can happen under certain circumstances, most common when you suddenly under eat calories by a wide margin.. i.e. you've been eating 3000/day for years, then suddenly start eating 1500/day.

So it's important to only go a little below your maintenance requirements.

If you still hit a plateau, just drop a little more, and repeat. You will push through the plateau, eventually.

>Why do conversations on certain topics have to degrade to nonsense if someone doesn't agree with your point of view?

Sorry, that's the Engineer coming out in me - when I'm thinking something through I always immediately think of the minimum and maximum case to better understand what's going on. I didn't mean to offend.

>Some people, me for example, can diet for a period, drop <x> pounds, and then I'm good for years with paying very little attention to diet - not everyone has it that easy though. But while I am dieting, I prefer to optimize it so it's over as quickly as possible.

You're a very lucky person.

>The idea of optimizing things is a fairly common theme on this site, but again, there seems to be something about the topic of dieting that changes the way people think.

I'm all for optimizing, and I personally think the calories in / calories out method is optimizing weight loss. I've never heard/seen a better and simpler way. It's the fundamental starting point of all diets - i.e. eat less energy than you burn.

> Does this actually happen, I don't know, but I believe from personal experience and reading forums that there is a phenomenon of hitting a weight plateau that is not explained by the simplistic calories in, calories out theory.

It doesn't. People are bad at self-reporting their intake. Reading forums isn't a good source of information.

Even if there was some kind of ultra-efficiency mode, it's worth noting that it doesn't mean calories in/calories out is wrong. It doesn't disprove the law of conservation of energy, I don't see why you think these two concept are opposed to one another.

The reality is that there is no special starvation mode or metabolic damage that makes people ultra-efficient food processing machines. The research doesn't support it and a bunch of forum posts of people self-reporting their intake (badly) or outright falsifying information (but everything on the internet is true!) isn't backing up your case.

If a person eats less energy than his body requires to function on a daily basis, where would the extra fat mass come from?

The body will burn it's stored fat to make up the energy deficit. The reason it stored fat in the first place is so that it will have energy to function when food supplies are not good.

Where exactly the body chooses to take fat from first, I don't know or care. Like digging a hole, it doesn't matter where exactly you take dirt from.

When there is no (or very little) stored fat, the body will start eating up it's own muscles to survive, but that's bad.

For weight loss/gain? If you're in a caloric deficit you will lose weight, if you're in a surplus you will gain weight. I'm not sure how much simpler I can state it.

Ah, so you've changed terms rather than answer the question, ok. People seems strangely emotionally attached to sides in this topic.

I haven't changed any terms, you added "for all people equally?" and I'm not sure what you mean by that. It's obvious the caloric requirements vary by individual and thus are not equal between people. But there is no magic starvation mode where you stop losing weight even if you are in a deficit.

I'm emotionally attached to people not using their critical thinking skills and thinking rationally, not about food.

The change of terms was "calories in / calories out" --> "caloric deficit", which ignores the stomach's efficiency in absorbing calories from ingested food (calories in), as well as individual metabolism (burn rate at rest, efficiency of caloric usage). Some people can absorb calories from food more efficiently than others, one theory with some scientific support is it is due to different enzymes in the digestive system.

> which ignores the stomach's efficiency in absorbing calories from ingested food (calories in), as well as individual metabolism (burn rate at rest, efficiency of caloric usage). Some people can absorb calories from food more efficiently than others, one theory with some scientific support is it is due to different enzymes in the digestive system.

But that changes nothing.

If you're a person that is bad at absorbing calories from food, then reducing the amount of calories you eat below what you burn will make you lose weight.

If you're a person that is very efficient at absorbing calories from food, then reducing the amount of calories you eat below what you burn will make you lose weight.

There is no difference. We're talking about a car that gets 30mpg and one that gets 50mpg. It makes no difference to each car, the only thing that matters is if you put in more or less gas than you use per day.

the error would be system and consistent and thus irrelevant. it would just appear that you had a faster than normal metabolism.

this has nothing to do with the fact that a caloric deficit will cause weight loss. you're moving the goalpost and talking about something completely different.

See my comment below. It's widely accepted there is indeed a starvation mode that we (and all mammals) evolved to deal with uncertain food supply.

When faced with severely less calories than it needs, your body can, for example:

^ Run at a colder temperature (ever notice you get cold really easily when you've been hungry for a long time?)

^ Not do such a good job replacing hair and skin cells (notice how hungry people have funny looking skin and "crappy" hair?)

Sorry but the amount of calories the body is capable of conserving by lowering temperature and cell proliferation is not as significant as you think.

Also the fact that there are processes to conserve energy says nothing about the level of caloric restriction necessary to achieve these conservation measures.

It's far from widely accepted.

If the body was able to go into 'starvation mode' and run more and more efficiently, famine wouldn't be such an issue. The fact that you think a western woman with a large caloric deficit is enough to engage some kind of magical 'starvation mode' laughable.

Why is it laughable? I don't at all see the logic here.

It's not a widely held theory in the scientific community.

It's more likely she's underreporting her food intake.

"If the body was able to go into 'starvation mode' and run more and more efficiently, famine wouldn't be such an issue."

If your wife has been in caloric restriction for an extended period of time, she may have metabolic damage. I recently stumbled upon Layne Norton's work - he has a PhD in Nutritional Science and is a bodybuilder/powerlifter, and he makes some compelling arguments (and reviews of the literature) about how the metabolism responds to prolonged caloric restriction.

Here's a good place to start: https://www.youtube.com/watch?v=QHHzie6XRGk

Interesting....again, this all sounds plausible, but is also contradictory with other perfectly plausible theories, some even in this same thread (whether low intensity cardio is good or bad).

Considering the plateau my wife's hit, I think maybe this is an avenue worth exploring though. She'll certainly be open to the idea of consuming more calories!

You know one thing that sucks, I would be not at all surprised if the average personal trainer at a gym hardly has a clue what they're talking about, not to mention the theoretical approach they subscribe to might not even be correct.

Metabolic damage is an overused term that layne has been pushing for a long time and makes a lot of money off of. I encourage you to read alan aragon's research review so you can see real research and how full of shit the whole 'metabolic damage' thing really is.

I've heard that plateauing is normal and that the solution is to increase the caloric deficit. If you're going to lose a lot of weight you'll hit a number of plateaus.

But as others have pointed out, 1200 calories sounds like a massive deficit. For the average, moderately active woman (requiring 2,000kcal per day) that would be a deficit of 800kcal, obviously way too high. I've seen 3.2kcal/lbs or 7kcal/kg of bodyweight recommended as a good deficit, which equates to 420kcal for a 60kg/132lbs person. As somebody else said, are you sure you haven't make a mistake in the calculations? This is very common mistake.

I think https://www.reddit.com/r/Fitness/wiki/faq#wiki_diet_details is a good starting point for more information, and then the whole of /r/fitness for more specific answers.

There are vast differences in caloric requirements between individuals. While I agree starting with an 800 cal deficit is severe; unless the woman had been tracking her food consistently and remaining weight stable you've know way to know if that was the actual amount of deficit she was in or not.

As a competing bodybuilder that has gotten to the extreme lows of body fat multiple times, I can say the best strategy is to just always be in a moderate deficit and diet for long periods. for example, start with a 100 calorie deficit, when you've stopped losing weight (because you have less body mass and thus a lower maintenance intake), cut another 100 calories or so. This way you're never in more than a 100 calorie deficit for the duration of the diet.

It's a mistake to make assumptions about her maintenance intake and assume she's in an 800 calorie deficit. If she was she'd be losing weight very very quickly.

  It's a mistake to make assumptions about her maintenance
  intake and assume she's in an 800 calorie deficit.

Agreed, but I think it was quite clear that I was speaking about a hypothetical person when I said "For the average, moderately active woman (requiring 2,000kcal per day) that would be a deficit of 800kcal" (emphasis added).

  If she was she'd be losing weight very very quickly.

That's why I suggested re-checking their calculations.

There are vast differences in caloric requirements between individuals.

Between a 2m tall man and a 150cm tall lady, yes. Between any two persons of same gender, similar height and mass, not that vast.

One study[1] noted that one standard deviation of variance for resting metabolic rate (how many calories are burnt by living) was 5-8%; meaning 1 standard deviation of the population (68%) was within 6-8% of the average metabolic rate. Extending this, 2 standard deviations of the population (96%) was within 10-16% of the population average.

http://www.ncbi.nlm.nih.gov/pubmed/15534426

People generally want to lose weight to be happier in some way, feel better about themselves and their value on the dating market, etc. not as an end in itself. If you swap negative feelings about your body for constant hunger, you're not improving the situation.

And personally, I'd take the self-esteem issues. You can at least make an attempt to talk and think yourself out of that box. Hunger is a deep, primal thing that can't really be addressed by a therapist or tuned out by reading a good book.

Reply on news.ycombinator.com