"A calorie is a calorie" violates the second law of thermodynamics
ncbi.nlm.nih.gov
ncbi.nlm.nih.gov
Calories derived from fat vs protein vs carbohydrates have different inefficiencies in converting them from their theoretical caloric value to their useful work in the body.
Fat is the most efficient with a loss of just @ 2-3%, carbs are at 6-8%, protein 25-30%. [edit Most of] this loss is in the form of heat.
It was not mentioned why this excess heat would not simply be offset by the body avoiding the normal processes it takes to maintain body temperature. Presumably the body generates enough heat as a by-product at room temperature and thus there is nothing the body can back off of to make use of the waste heat described above.
> Some of the available energy is lost as heat and in the internal rearrangement of chemical compounds and other changes in entropy.
So not all of the difference in efficiency is made up in the form of heat. Unfortunately, I don't remember enough biochemistry nor thermodynamics to dive deeper into this, but I think this article is a good starting point for a discussions, which has otherwise just been dismissed with the "a calorie is a calorie" argument.
When people overeat grossly, those 5% won't make much of a difference. On my binge days, I consume upwards of 5000 kcal and it doesn't really matter if it's actually just 4750 kcal - it's still too much.
So yeah, in practice, a calorie is pretty much a calorie.
The study this cites early on suggests that a low-carbohydrate diet with N calories a day is roughly equivalent to a low-fat diet with only 70% of N calories a day. So a 2000 calorie-a-day low-carbohydrate diet is equivalent to a 1400 calorie-a-day low-fat diet. That result is huge. (And makes me regret having had pasta three times this week!)
As other people said, the results of this study are not new. We learned that in basic biochemistry when the metabolic pathways were discussed.
> So a 2000 calorie-a-day low-carbohydrate diet is equivalent to a 1400 calorie-a-day low-fat diet.
It is so not.
Perhaps there is some reason to doubt this study, but saying "It is so not" is hardly a rational rebuttal.
People aren't fat because they are consuming 2500 calories from a Big Mac and Fries rather than 2500 calories from carrots. People are fat because they are consuming 6000 calories and burning off 1300.
The message is simplistic, sure. For a large majority of overweight people though that's all that is required. Somewhere between reducing caloric intake and becoming fit, the message that not all calories are created equal sinks in, if for no other reason that it quickly becomes apparent that you'll starve only eating one meal of McDonald's a day.
Why are people consuming 6000 calories? They are always hungry and eat too much food.
Why are they always hungry? They eat and drink too many carbohydrates. Too many carbohydrates leads to high blood sugar which leads to too much insulin. After the insulin does its job, the blood sugar crashes causing hunger. The cycle repeats, causing problems including insulin resistance, excess fat storage and type 2 diabetes.
What is the solution? Don't consume carbohydrates and avoid the hunger/sugar/insulin cycle.
The only mention of carbohydrate's effect is because it's chosen as a large, easy number to reduce in favor of raising the protein amount, raising the overall inefficiency of the system. They listed, in Atkins-like diets, that shifting from 55% carbs to 8% carbs (with the change going to increased protein intake) results in about 140kcals less useful energy.
That's it. From where in the article are you drawing insulin/diabetes/hunger connections?
As soon as your insulin spikes due to high amount of carbs ingested, your body immediately starts to convert excess carbs into fat.
I've done very low carb diets and easily lost 20 lbs in a month even though I've never weighed over 200lbs. Its pretty difficult though.
After stating that the now-great-great-grandparent had missed the point of the article, they proceeded to talk entirely about things not at all contained in the article. I'm sure there's a better term for it, but the post is pretty blatantly contradictory in that way.
Upvoted y'all :)
What about it? It's not necessary. If you look for it, you can find lots of examples of societies that were quite healthy on diets that weren't "balanced". One popular example is the Inuit, who got 75% of their energy intake from fat (largely seal and whale blubber) because that was what was available to them whereas fruits and grains and vegetables were not.
I do know that I will have to track my weight and count calories for the rest of my life. That’s ok. (As a teenager I already lost a substantial amount of weight with the same method but I gained it all and more back because I stupidly stopped tracking my weight and counting calories. I’m confident that I won’t make the same mistake again.)
But yeah if you want to eat carbs and be healthy you have to basically count calories for the rest of your life.
Counting calories is not that hard. I can do it in my head by now. Tracking my weight (which, I think, is equally important, especially for motivation) is more or less a reward and not a chore by now.
As someone who does not get food cravings and does not have blood sugar regulation issues, it's hard for me to understand, but the only way some folks can manage to eat less is by banning certain foods from their life.
Perhaps it's a diet of coffee/cigarettes (appetite suppressants) that made me go from 200 lbs to 172 in a year but oh well.
I used to eat rice, pasta, potatoes, and bread all the time. I only miss the bread, but I make exceptions when I go to a restaurant and they have a really good bread.
Can hard boil eggs with minimal attention (set the alarm on your cellphone), can make 6 or 12 at a time and those will last you a couple days.
Get some vegetables that require minimal preparation - I used pickled vegetables and like them, but canned would be fine too. Maybe tuna or sardines, try them all and see what you like.
Then you've got rice+beans, and you add on some vegetables to it, and then either hard boiled eggs, tuna, or sardines - fast, cheap, healthy.
Putting it in practical, personal terms -- I was laid up for six weeks for medical reasons this winter, and my bad habits continued for the next six weeks as well. Over that period I gained about 18 pounds, one of the worst periods of weight gain in my life. Simple math (and ignoring the data presented in the article!) tells you I must have been eating about 5250 excess calories a week. Roughly speaking I was probably eating 23,000 calories a week when I should have been having 18,000.
Now suppose I had gained that weight on a low-fat diet. The study cited in the article suggests that if I had been on a low-carb diet instead, I wouldn't have gained any weight at all! That's a pretty significant result. (Of course, in practice I was on a "whatever" diet.)
For those of us living on the edge, trying to shave off 500 calories a day, the knowledge that not all calories are created equal is a Big Deal.
For your example: If you had eaten a low-carb diet, you'd probably need to have eaten 50% more food in terms of quantity in order to meet the caloric intake you were getting on the "whatever" diet.
That's my point. If you simply focused on the caloric intake and kept it at 18,000 a week (which seems high for someone lying in bed, to be honest) and still ate whatever you wanted, you would't have put on 18 pounds.
That said, what really interests me is the mechanisms behind addictions. Why do smokers smoke, knowing full well by now that it will kill them earlier than non-smokers? Why stuff obese people themselves, knowing full well that it will cause serious health issues down the line.
Bottom-line I tend to agree with those who hold that 'a calorie is a calorie' and simply cutting down on food intake is a good enough principle, though perhaps not entirely scientifically correct, for the majority of obese people.
But why don't they do it? What makes it so attractive that they simply ignore the serious long-term disadvantages - and even in some cases deny the existence of said disadvantages even though in reality they must know they are real.
Let's take this one step further: Is the reason/mechanism a smoker smokes the same why I browse reddit and HN all day instead of working on my PhD?
http://news.ycombinator.com/item?id=2254906
The researchers who wrote this paper looked under that rock. (In this case, pop-science application of fundamental physical law. It's hard to get more fundamental than thermodynamics.)
(An example for you entrepreneurs out there, I'd suggest looking under Kerchoff's Law. Yes, it's a great principle to keep in mind when designing security tools like ciphers and cryptographic protocols. However, I contend it's applied in a counter-productive way when people think about real-world systems -- those have boundaries that are way too complicated for the application of Kerchoff's Law. Often, this is just an opportunity for someone to show they understand crypto theory, then throw up their arms and declare nothing can be done. However, the truth is that security often works or doesn't work because of the economics!)
It's much safer and simpler to lose weight and improve overall health by simply not eating crap (which is quite hard to do in a typical western country, I agree) and having regular exercise.
I can only recommend everybody to stop loading huge amounts of carbs, specially sugar. Go for simple unprocessed foods, like fruits, vegetables, meat, fish, and so on.
The paleo lifestyle works just fine for me. I know it is hard to convince other people to do it. Even when they see me eat like I do, and they have seen the change in other people that adopted that practice, most people simply resist the idea. Check out http://www.scientificamerican.com/blog/post.cfm?id=mummy-say...
http://bodezfitness.com/blog/tasso/post.cfm/post/4841/2-pre-...
Why? Protein-rich food tends to weight less, doesn't cause as much bloat. Actually a very high fat diet might cause most loss in the beginning. For example I eat a very high-carb diet,a lot of raw food that is not too calorie dense, it bloats you a lot providing few calories at the same time. If one day I decide to eat only ice cream (keeping ammount of calories the same) then on the next day there will be a sudden big loss. Of course it will be gone once back to eating what I eat before.
So when measuring efficienct of a diet you should exclude anything that happens in the beginning because it's always very very volatile in that stage. Especially when subjects tested ate a very different diet beforehand. You could also go on to talk about sodium intake which affects water retention which translates to changes in weight. That will cause a lot of fluctuation in weight in the beginning too.
I keep a very detailed log of what I eat and my weight with CRON-o-Meter. When I eat and drink same food for an extended period of time (and stay home all the time) my weight loss is almost calorie-perfect, meaning that you could convert the daily calorie deficit to grams and this is how much I would loose on each day. Only once every 4-5 days there would be a slight "bump", but if you look at the 7-day moving average it's virtually a straight line.
I went on vacations once and decided to binge, big time, 6000 calories a day (really!), at the end of the day it was very unplesant, but well the food was worth it, haha. Keep in mind that I weight 110lbs and eat around 1700 on a normal day. The weight of my body has increased probably by around 5-6 kg, 4kg was expected, rest was water retention etc. So the first few days back on a diet were crazy. One the first day a loss of 1.3kg (and that is after a 2 day fast already!). Next day 0.3kg, then 0.2 kg, 0.15kg, one day of no change and then a sudden increase of 0.6 kg, after that it gruadually stareted to approach the expected rate of loss (0.1kg/day).
Many people, when they begin a diet are very much like me going off a binge. Not as dramatic of course, but similiar. In a choice of different food can yield a big loss that won't be there long term. A lot of fad diets exploit that fact and so do high protein diets. People often go on those diets, loose even up to 5-10lbs purely because of eating a food that digests and affects water retention in a different way and maybe some other factors that I don't know of (10 would be a lot, but I guess plausible for a very fat individual). Some get satisfied with that small loss, go back to the old diet and then we hear about the mysterious "yo-yo effect", but in fact nothing strange has happened. Those that last and continiue the diet will often say that the "starvation mode" has kicked in. No, "starvation mode", the "water retention effect" is gone (simplification). Some, after hitting the "starvation mode" will even swtich to more calorie dense food increasing their total intake of calories but reducing the sheer volume of food and claim to have beaten the "starvation mode" with more calories. I even consciously use those tricks to manipulate my weight sometimes (as there it can affect my mood :-) ).
I guess you understand by now. Unfortunately most studies fail to account for that, so whenever I see a study that tries to prove something with a small sample size, conducted over a short time frame I'm very very skeptical. But then again, once your sample size and time frame get bigger controlling those people gets hard, too hard. You have to make sure they eat the exact ammounts of food they are supposed to eat. They sometimes give people directions like eat one cup of this, 2 cups of that, CRAZY! You have to portion the food for them, unless you explain what a "cup" of any given food is and make sure they PERFECTLY understand you will have huge errors even with 100% honest people. Accounting for bias is very tricky with those studies too, not going to work too good. Psychological effects actually get stronger and harder to control the longer the time frame is, so large N and a long time frame doesn't solve the problem either. Physical activity is another thing. Some people burn 200 without noticing. There's very few people that truly have naturally "fast metabolism", yet a big proportion of people that are thin claim to have that. "I eat whatever I want and stay lean", yea you do eat whatever you want but you don't want to eat much. Or they do sports. Or fidget all the time (which some claim could even burn off 500 in extreme cases).
Do a study with each group having at least 30 people, same gender, similiar weight, similiar height, healthy, close to no physical activity, not a fidgeter. Portion food for them, don't let them do it themselves. Measure everything they put in their mouth, water and multivitamin included. Weight each day at the same time, same clothes, make sure they pee beforehand. Do that for 3 months. Discard first 2 weeks of results. Perhaps the last 2 weeks too (people are more likely to cheat at the end). That's a study that I might care about, of course probably forgot about 20 other things I'd do.
I think conducting such a study would only be possible if you gathered a large group of dieting/nutrition enthusiasts like me. Too hard otherwise. I really sometimes wonder how they find people for those larger studies.
Getting my mom to diet was/is a BIG pain even given the fact that she was willing to drop some weight. She was also extremely biased in a lot of things she said even given that she probably knows more about nutrition then the average person as I give her a lot of lectures :-). Now try that with 100 "normal" people that you probably DO NOT control on a daily basis. I know for a fact that unless you drug those people, they are BIG enthusiasts or lock in a cage and monitor the bias will be enormous.
I could go on talking for a very long time. The conclusion is pretty simple. Most studies about weight loss are simply useless. There are many smart people in the field of nutrition I'm sure, unfortunatelly it's very very hard to find these amongst legions of incompetent people. I mostly see 2 kinds of the incompetent. One group is those that are simply stupid/lazy/don't care. They do a study to seem smart, probably because they need it to get some kind of a credential. They study something that 100 people already did, change two things, come up with a conclusion that is not too controversial so there's not too many people questioning (when you're findings are interesting everybody is going to point out even a slight flaw in the study, if you say what people want to hear you might get away with a large, fundamental flaw, because you state "the obivious" anyways). Another group of incompetent people are something I'd call the "ideology-driven", those are scientists that will do anything to prove their thesis. Actually I think those are a little better than the first group of the incompetent. You see, the stupid/lazy ones, they have almost a zero chance of comming up with anything interesting. The ideology driven ones can actually find something interesting.
Ok, well I'm tired writing that long rant on the field of nutrition (but I guess it applies to so many more fields of science). If you was bored enough to read the whole thing please also keep in mind that I admittedly have no education in that field, or any whatsoever, so everything I wrote is basically based on my personal experience and what I read on the Internet. But I do not think I have said anything that is far from the truth.
So as to that particular study, their reasoning might be right, but I wouldn't use that data to substantiate it. They are honest people though as they do explicitly say "one can't predict that the ratios will stay the same over a long term dietbut the calculations show that the possibility of metabolic advantage should not come as a surprise." And I'm afraid that the advantage would wear off. Also note that I'm not saying that I know from my experience that it does, because I have never really went long term on diet that's not high carb, I hate low-carb stuff. I only have tons of experience with short term effects and what I see in most studies are those short term effects that I know a lot about.
Also, I always pay attention to food labels and never noticed any confusion. As far as I can tell the units on Nutrition Facts label are always correct.[1]
Also note: a giant tree doesn't dig out a giant hole where it grows in the ground. The dirt isn't the bulk of the tree's wood.
Regarding the tree, you're absolutely right. If only you were a tree that would be a useful comment. Unfortunatly the metabolic process of a tree (all plants) is different to that of an animal. A plant requires water, carbon dioxide and sunlight. Throght the process of photo-synthesis (which only plants can do) carbon is removed from the atmosphere using sunlight as the primary fuel. So, if you like a plant "breaths" sunlight, "eats" air and defecates oxygen.
Maybe your heartbeat could also work; that's also pretty easy to collect.
It'd be awesome to have a running total of how many calories I'm burning at all time.