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Scientist busts myths about how humans burn calories

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Re: Scientist busts myths about how humans burn calories

#521

Post by irthomasthomas »

jghn wrote: post #520
irthomasthomas wrote: post #508

Earlier quoted context omitted.

Not really. E.g. look at my second example, cold potatoes vs hot potatoes. Same calories, same exact ingredients, but hot potatoes are significantly worse than cold potatoes. I dont have the link to hand, but there is a GL database maintained by Harvard, I think, that demonstrates this. I will look it up later for you.

It’s still calories in vs calories out. What changed is that our understanding of what determines calories in and calories out has become more nuanced. For instance, your examples

My examples demonstrate that calories in / calories out is false. I don't quite get your point? A calorie is a measure of the useful energy released from burning stuff in a furnace. It was invented to compare the efficiency of different fuels for steam engines. It has no relevance to humans, who don't use a furnace and steam power, but a complex chain of cascading chemical reactions.

Re: Scientist busts myths about how humans burn calories

#522

Post by marcus_holmes »

mantas wrote: post #458
1_player wrote: post #382

Earlier quoted context omitted.

> What's so controversial about it? Your body burns incredibly more energy just "being there" than you burn moving about. Exercise certainly increases your calorific expenditure, but it's much easier to ingest less fuel than to run 5 more miles because you had a portion of fries. There are benefits in exercise, apart from the obvious ones the raising of the baseline metabolic expenditure, because muscles are expensiv…

> Your body burns incredibly more energy just "being there" than you burn moving about. Bullshit. My body goes through 1600-ish kcal on an idle day. If I go out on a 4h steady bicycle ride (= 100km), I go through 2000 kcal on ride alone. That’s much more than my body burns just being there.

Did you read the article? because this specific thing is what the science that the article covers explains.

tl;dr: your body burns roughly the same amount of calories regardless of exercise. However, it allocates those calories differently: if you don't spend them on exercise then it will spend them on stress (and presumably other stuff).

Which totally makes sense as to why my depression & anxiety fade if I run or work hard.

Re: Scientist busts myths about how humans burn calories

#523

Post by csee »

Xcelerate wrote: post #487

The article seems to miss what is (at least to me) the most interesting follow-up question: if exercise doesn’t cause a person to burn significantly more Calories throughout the day to induce weight loss, then what does? I’m somewhat hard-pressed to believe the answer is diet alone. Anecdotally, when I was running 100 miles per week in college for cross country, I ate three or four giant meals per day and maintained…

The article proposes stress and inflammation.

Re: Scientist busts myths about how humans burn calories

#524

Post by jvvw »

wyldfire wrote: post #159
makeitdouble wrote: post #151

Earlier quoted context omitted.

> losing weight happens by eating less To note, when they refer to "diet" it's probably not about "eating less" or popular "on a diet" interpretation. Good and bad diets also aren't as simple as the "CICO" myth

It seems to me that CICO is less of a myth and more of an "incomplete model." Having a model is an improvement over no model at all, even if it's oversimplified IMO. For very overweight people it probably doesn't matter quite as much. If you had an accurate & sophisticated model for how the foods one eats contribute to their fitness / health / appearance, it probably would be too unwieldy to apply. A daily sum of cal…

Just been reading Why We Eat (Too Much) by Andrew Jenkinson and he is basically saying this - that CICO is true but there is also this feedback system with the 'Calories Out' part so that our body adjusts to physical activity levels (as described in the article) and also to what the 'Calories In' part it is. So while restricting calories in works short-term your body adjusts and also decreases the 'Calories Out'. His argument is that the problem for most people overweight is leptin resistance interfering with the body's feedback mechanisms and basically you need to fix that rather than try and changes either the 'Calories In' or 'Calories Out' directly.

Re: Scientist busts myths about how humans burn calories

#525

Post by bluecalm »

I would like to see some answers on this one. First, why are we adjusting for lean body mass? I mean if you're 120kg with 50kg of extra fat you will obviously burn more calories by carrying that around. Someone who doesn't have additional 50kg of fat will need to exercise to burn the same amount of calories. It's well known in fitness circles for years now. It would be surprising if lean sedentary people burnt as many calories as active ones.

The limit of 4650kcal per day doesn't sound right. A lot of endurance athletes, even amateurs, burn more than that. How much you can digest is limited (common wisdom is 60-90g of carbs per hour when exercising which is 240-360 calories). Still there are also glycogen stores for additional 1500-2000 kcal as well as your fat stores which are heavily in use during long lasting endurance effort. I assume the limit is meant for long term which would make more sense.

The fact about ultra marathoners who burnt 6200 kcal at the beginning of the race but only 4900 at the end is interesting. Assuming they weigh say 60kg then it takes around 2500kcal to run a marathon. There is a lot of other stuff going on if they burnt 6200 per day. It would be interesting to see if there aren't other information that explains the difference (like hills for example).

Re: Scientist busts myths about how humans burn calories

#526

Post by projektfu »

Xcelerate wrote: post #487

The article seems to miss what is (at least to me) the most interesting follow-up question: if exercise doesn’t cause a person to burn significantly more Calories throughout the day to induce weight loss, then what does? I’m somewhat hard-pressed to believe the answer is diet alone. Anecdotally, when I was running 100 miles per week in college for cross country, I ate three or four giant meals per day and maintained…

Fat stores are considered, metabolically, as stored energy as they expand and diminish based on the metabolizable energy of the diet, which may be different from the measured total energy.

But you’re definitely right! There’s a great Mr. Wizard-style TEDx video about it: https://youtu.be/vuIlsN32WaE

Re: Scientist busts myths about how humans burn calories

#527

Post by vanderZwan »

vanderZwan wrote: post #412
TulliusCicero wrote: post #391

Earlier quoted context omitted.

> My take away was fitness should be a lifestyle There's only one way this actually happens for a majority of the population: exercise being built into daily habits, in a way that's so natural that it almost seems unavoidable. The Netherlands seems to have the right of it: their urban design strongly supports walking and biking, and indeed, their rates of 'active transportation' are very high. As a bonus, walk and bi…

"Traditionally" the people of Osaka, Sicily and various Greek islands are actually best at maintaining such healthy lifestyles, from what I recall from studies on longevity. Good diets, lots of mild exercise from long walks (on hilly terrain) and strong socal ties. I say traditionally because of course these studies can only really look at the lifestyles of past generations. With that in mind the flat landscape of th…

*Okinawa, not Osaka. Serves me right for trying to recall these things from memory before my morning coffee.

Anyway, search for "blue zones" to learn more, aging healthily is an ongoing topic of research

Re: Scientist busts myths about how humans burn calories

#528

Post by dmitrij »

It's nice when science confirms personal experience.

Early 2020 I started to change my life. Exercise, healthier food, weight control. My conclusions: I got stronger, had less back pain and less fat, felt calmer. Weight went down significantly.

After restaurants opened, I started again eating more fat and drinking more wine while continuing exercising and eating healthy at home. Strength and calm stayed, weight got up.

My conclusion: exercise is good in any aspect, but weight control also needs control of calories intake.

Re: Scientist busts myths about how humans burn calories

#529

Post by 14 »

ehnto wrote: post #315
14 wrote: post #218

I came up with a diet to lose weight. I was approaching 200lbs and wanted to get it under control so made a simple diet that helped me lose 50lbs. I call it the half and half. You take your meal and plate it. Then take a second plate and split everything exactly down the middle. Eat your first plate and then you wait half an hour. If after half hour you want to eat again you can go back to your second plate. What end…

You might have heard of it by now but I suspect you're exploiting the mechanism that delays the feeling of satiation for roughly 20 minutes after eating. Many people can eat a seemingly unlimited amount of food so long as they do it quickly. I think your method is cool because it tricks both the hungry and the logical part of your brain into thinking it can totally have all the food so long as it waits, but by the ti…

Thank you. A lot of people just shrug it off when I say I have a diet. They look at me and say but you are skinny like you ever needed to diet. Well I really was 50lbs heavier at one point and that is a lot. I think you nailed on the explanation as to why it happens as well. When you know you can go back for more it’s not some painful I need to starve feeling you can reason with yourself and say okay I had my first plate it’s not going to be bad to wait half an hour where as if you had to wait say several hours you may be tempted to have just a bit more because of hunger pains. Also not being restricted to certain foods makes it easier as well because who really wants to make a big change to the foods they already eat. Well thank you for commenting.

Re: Scientist busts myths about how humans burn calories

#530

Post by mannykannot »

TheSpiceIsLife wrote: post #41
mannykannot wrote: post #29

Earlier quoted context omitted.

This is purely anecdotal, with a sample size of one even if it is right, but it seems to me, personally, that exercise suppresses my appetite to some extent. I can't say that this is even real, but if it is, my best guess as to why this might be is that the exercise subtly stimulates/irritates my gut such that I am de-motivated to eat, either by feeling full or subliminally 'sick to my stomach'. After running a marat…

some would argue that running a marathon isn't exercise and shouldn't be considered as such. Whether any one in particular subscribed to that school of though or not, marathon running is an outlier event, and isn't what most people would consider as part of a regular, healthy, exercise regime that one might do many times a week.

To be clear: I only mentioned that marathon because it was a particularly clear case of the effect exercise seems to have on my appetite, and I am not recommending it as an exercise regimen.

And while it is not for most people (and definitely not me), there are people I know who thrive on running marathons and the training for it, while otherwise living perfectly normal lives. There is a hypothesis that cursorial / persistence / endurance hunting was a a stage in our ancestors' evolution, and that we have inherited some of the traits of that lifestyle.

https://en.wikipedia.org/wiki/Endurance_running_hypothesis

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