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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

#631

Post by mardifoufs »

wildmanx wrote: post #572

Irony. A linked article describing a scientist trying to rigorously find out how weight changes and energy expenditure and diet are connected, revealing the little we do know and the vast sea of what we do not know. The discussion here: full of anecdotes and bro science berating one another "that's not how it works, it works like this", "I personally do this-and-that", "you just have to x-y-z, it's that simple".

Yes, but this is one study out of thousands. It's not because it's a paper by PhDs that you just have to take all their results as the new truth and ignore the rest of the literature. It's way way more "bro science"-like to just look at the latest controversial study/paper/research's results while ignoring everything else. Consensus is important and even more so with such a controversial result.

Also, how is it bad for people to contrast what they see in real life with what the study shows? Michael Phelps and other athletes actually eat more calories, that's a fact. So it makes sense to question why that would be the case if the conclusion we see here was true. Again, a scientific paper isn't the bible-you can actually question it, and you don't have to just accept it as truth.

Re: Scientist busts myths about how humans burn calories

#632

Post by NoboruWataya »

masklinn wrote: post #284
throwaway09223 wrote: post #118

Earlier quoted context omitted.

> if I go all out on a row machine for 30 minutes, I'll burn 300 calories. A stationary bike at a steady 20mph pace is about 500 calories in 30 minutes. That's really significant. An hour will erase about a third of a normal person's diet. When I used to do heavy training (long distance running, weight training) I would eat close to 8k calories a day and I was in fantastic shape. Eating more was necessary to survive,…

> A stationary bike at a steady 20mph pace is about 500 calories in 30 minutes. That's really significant. An hour will erase about a third of a normal person's diet. That assumes a “normal person” will not compensate for the effort with a snack. A “reward” pint of ice cream will re-add more calories than the hour of cycling. A “standard serving” will nearly match your half hour. And that’s an hour at 20mph, which re…

> That assumes a “normal person” will not compensate for the effort with a snack.

You're also assuming the same normal person will not compensate for their healthy lunch with a snack.

Re: Scientist busts myths about how humans burn calories

#633

Post by kerneloftruth »

dahart wrote: post #4

> “You can’t exercise your way out of obesity,” […] “you can’t outrun a bad diet.” While this article is being a bit dramatic and possibly understating the impact of exercise slightly, I feel a little dumb that I didn’t know this earlier. It took me several decades too long to understand the obvious, that exercise is for building strength, and losing weight happens by eating less. I tried for way too many years to ex…

Yes, many people are selectively deaf to the phrase "combined with a sensible diet" when it comes to weight loss, or other health advice. I'd venture that it's subconscious desires to keep the food intake that invoke mental filters to just not hear that part; or, to rationalize that your food intake is ok.

Re: Scientist busts myths about how humans burn calories

#634

Post by samatman »

hdjjhhvvhga wrote: post #360
ajuc wrote: post #192

Earlier quoted context omitted.

Yes counting calories is essential, I had very similar experience (walk 10 km on the weekend ~= burn 600 kcal, then buy a 1000 kcal snack on the way back and wonder why I'm not losing weight), but still the exercise makes a big difference. Last year in march I started counting calories, recording my weight and all exercises I did and walking/biking every day. I lost 30 kg, walked 2100 km, biked 1000 km, and the sum o…

> the sum of calories burned by all exercise was about 160 000 I believe you meant kilocalories

Can you show me a representative sample of places where English speakers refer to [unit of energy] burned by exercise and mean anything else other than kilocalories while saying anything else other than calories?

No, you can't, you're showing hypercorrection and lack of fluency.

Re: Scientist busts myths about how humans burn calories

#635

Post by uberduper »

nradov wrote: post #166
timr wrote: post #137

Earlier quoted context omitted.

I have also done almost exactly this process, and it worked for years to regulate my weight. But then I hit a plateau (a high plateau, not a low one) where I was unable to drop weight no matter how low I cut my calories. I started at a range that I knew had worked in the past, and lowered it over the course of weeks, well past the point where I was miserable. I even tried more complicated things, like varying my inta…

The most likely possibility is that you were simply underestimating your calorie consumption. A lot of people forget to count the creamer in their coffee, the candies from the office break room, the little tastes while cooking dinner. Unless you have a severe metabolic disorder your body will only burn lean muscle mass as a last resort when you have exhausted glycogen stores and can't sustain the energy demand from f…

A catabolic state induced by caloric deficit will absolutely consume lean muscle mass regardless of the availability of fat reserves. Muscle stimulus (via weight training, for example) and sufficient dietary protein can prevent this. But if you're just dieting without specifically controlling this, you will lose muscle along with the fat.

Re: Scientist busts myths about how humans burn calories

#636

Post by jsmith45 »

waterhouse wrote: post #322
_9omd wrote: post #129

Earlier quoted context omitted.

Yeah, that's a very good point. This is kinda getting off into the weeds from the original point, but interesting weeds nonetheless :). This study[0] says that measuring CO2 is not enough, and that indirect calorimetry is the gold standard for measuring energy expenditure (EE). "Calculated EE based on CO2 measurement was not sufficiently accurate to consider the results as an alternative to measured EE by indirect ca…

Let's consider a specific example: Lactose intolerance. The Wiki page for it is pretty good. So, despite the name, lactose intolerance refers to lacking the enzyme lactase, which is used to break down lactose. If you have lactase, then your human cells can use the calories from lactose; if you don't, then the bacteria get the lactose. Wiki says "Symptoms may include abdominal pain, bloating, diarrhea, gas, and nausea…

> Lactose is a specific, well-understood example of some people absorbing nutrients much better than others. I think there are other examples, and I expect there's a lot of variation in absorption efficiency that's less known. When you hear about people who eat lots of food and remain thin, I suspect this is part of the explanation. And whether their bacteria get the calories instead, or whether it passes through untouched, might show up in CO2 measurements but I don't think it would be related to body fat accumulation.

Yeah, the blind assertions I have seen that people basically always absorb pretty much 100% of the calories of the food is weird. We already know that some forms of calories like fiber have very low absorption rate. The Atwater indirect system of calculating calories takes that into account, but is still just an estimation, since it uses average calorie values for protein, carbs, and fat.

And so I've just noted that calories on packaging is just an approximation. An individual food may actually have more above average proteins than below average, etc, which can skew the real calorie count. For example, nuts are known to have less calories than indicated on the label, with whole almonds having 20% fewer. (https://doi.org/10.1093/jn/138.9.1741S) This is also ignoring the fact that many foods, especially those prepared by people are not always super consistent in sizing. A subway sandwich prepared correctly should on average have the calories subway claims, but we all know that some locations will follow the correct procdure more closely than others. Etc.

The other issue with just blindly going with calorie counting (which is really on tracking calories in) is that the differences in the calories one takes in will cause changes in the calories one expends. Eating fairly substancially less than your body is used to will almost certainly cause one to feel bad, and avoid doing as much, meaning fewer calories out, at least partially offsetting the the calorie reduction. But people are generally not measuring the calories expended very closely, if they bother doing it at all.

Re: Scientist busts myths about how humans burn calories

#637

Post by nightski »

fredophile wrote: post #240
nightski wrote: post #181

Earlier quoted context omitted.

How is it ambiguous. You clearly understood I meant calories burned per unit time.

The ambiguity is what unit of time you care about. With HIIT you lose more weight per minute of exercise you do. With a lot of LISS you can lose more weight per week than you could with HIIT.

Understood, but the parent I responded to was talking about efficiency so I thought that was the context.

In my experience I'm not so sure about that either. I can't repeat centuries day after day when I am out of shape and need to lose weight. If one can, it's very unlikely he/she needs to lose weight.

Re: Scientist busts myths about how humans burn calories

#638

Post by makeitdouble »

yoz-y wrote: post #355
thisisonthetest wrote: post #162

Earlier quoted context omitted.

CICO is almost as pernicious and ubiquitous. It really grinds my gears when people try to use “intuition” to understand something super complex with no data at all. People talk about “metabolism” the same way. Say the word “toxins” around me and I will fight you in the streets.

CICO mostly doesn’t work if you count the calories wrong. But if you don’t eat 1000kcal under your actual TDEE, there is little chance you will not lose weight (barring severe health problems). If you metabolize less or more doesn’t really matter as it gives you a hard maximum of what you could potentially ingest (both in the TDEE calculation and the restricted diet)

> there is little chance you will not lose weight (barring severe health problems).

And you will probably either have severe health problems, either have a reduced metabolism to the point you can’t properly function on a day to day basis.

You’ll either give up, the pendulum will swing the other way and rebound your weight, and people will blame you for being too weak.

Or you’ll push through, lose your job and/or continue develop eating disorders, hopefully you’ll realize you can’t go on and give up, or you’ll get medicated, with side effects affecting your appetite and weight ingestion, might still end up rebouncing and get blamed for it.

You’ve got a snow ball’s chance in hell that you can keep your intake very low and be fine with it for the rest of your life, but then you’re probably already healthy and pretty normal weighted, because I don’t think anyone who can just stop eating extra would stay overweight for long with the pressure we apply on obese people as a society.

All of the above is really just par for the course for people who get told “just do CICO”. People for which it actually kinda works don’t usually need to be told anything in the first place.

Re: Scientist busts myths about how humans burn calories

#639

Post by eli_gottlieb »

throwaway09223 wrote: post #118
geoduck14 wrote: post #70

Earlier quoted context omitted.

>A lot of people know this already, so it’s not busting everyone’s myths It is still worth mentioning - because it is so easy to overlook. Some simple math: if I go all out on a row machine for 30 minutes, I'll burn 300 calories. If I eat 2 extra slices of pizza, it is easiely 300 calories If I swap a turkey sandwich with healthy options, I can reduce my linch calories by 300 - and I can save even more during dinner…

> if I go all out on a row machine for 30 minutes, I'll burn 300 calories. A stationary bike at a steady 20mph pace is about 500 calories in 30 minutes. That's really significant. An hour will erase about a third of a normal person's diet. When I used to do heavy training (long distance running, weight training) I would eat close to 8k calories a day and I was in fantastic shape. Eating more was necessary to survive,…

>An hour will erase about a third of a normal person's diet.

Pretty sure most people shouldn't be eating 3000 calories/day.

Re: Scientist busts myths about how humans burn calories

#640

Post by everdrive »

dahart wrote: post #4

> “You can’t exercise your way out of obesity,” […] “you can’t outrun a bad diet.” While this article is being a bit dramatic and possibly understating the impact of exercise slightly, I feel a little dumb that I didn’t know this earlier. It took me several decades too long to understand the obvious, that exercise is for building strength, and losing weight happens by eating less. I tried for way too many years to ex…

I had a friend who wanted to lose weight, and so he’d walk about one mile to a local restaurant, where he’d proceed to eat a 1,200 calorie meal. It’s not as if he didn’t burn calories while walking, but he severely overestimated how many calories he had burned.
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