[boneheadmed]

As a practicing Endocrinologist I will go out on a limb and say excess carbohydrates are the problem leading to obesity. Sugar (or sucrose) is a particular problem as it will stimulate insulin release from the pancreas. Insulin promotes storage of glucose and I am convinced, the growth of fat cells. I have seen patients lose a tremendous amount of weight (34 lbs over 7 months) and lower blood glucose and their amount of diabetes medication simply through cutting out sugar and flour. They also reduced their overall carbohydrate intake. I presented the data at our annual Endocrinology conference recently. https://endo.confex.com/endo/2013endo/webprogram/Paper9044.h...

[magnusson]

As a practicing internet commenter I will go out on a limb and say that's nonsense. Sugar tends to promote overeating because it makes foods highly palatable and rewarding to eat, but it doesn't cause fat gain independently of an energy surplus. See Surwit et al, Metabolic and behavioral effects of a high-sucrose diet during weight loss. http://www.ncbi.nlm.nih.gov/pubmed/9094871

Obese women consuming a hypocaloric diet with 71% of their daily energy as carbohydrate and 43% of it as sucrose had no trouble losing fat. "Results showed that a high sucrose content in a hypoenergetic, low-fat diet did not adversely affect weight loss, metabolism, plasma lipids, or emotional affect."

Moreover, all carbohydrates, as well as protein, stimulate insulin release, and insulin is not in itself problematic: http://weightology.net/weightologyweekly/?page_id=319

Reducing carbohydrate intake can be an effective weight loss method, but that doesn't mean that carbohydrates intake is uniquely responsible for obesity to begin with. http://wholehealthsource.blogspot.com/2011/08/carbohydrate-h...

All of the world's longest-lived populations consume carbohydrate as their primary macronutrient.

[mixmastamyk]

No one serious is saying it is uniquely responsible. Just that the more sugar and starch eaten, the less time the body can stay in fat-burning mode, which is well known. Perhaps the obese-hypercaloric would have lost more with less sugar.

All the other variables and laws of physics still apply.

[encoderer]

The latest research I've read (I'll edit with a link once I get back to my desk) and my own personal experience suggests that: A calorie is a calorie is a calorie.

All the fad diets that cut out a certain type of food all really just work because of calorie restriction. Look at the "cookie diet" for an example.

For me, I'm 6'2, I went from 210 to 175 over 10 months (while adding significant muscle mass, suggesting fat loss of 40+ lbs). I did this by changing my diet: I eat nothing for breakfast. One cup of coffee with cream. For lunch, I eat only fruit. Seasonal. Always an apple, sometimes two, berries and grapes, that sort of thing. Sure they're good for you in a non-processed-foods sense but they also are very high in sugar.

I eat a very large dinner.

I always, always eat dessert. Always.

I work out 3 mornings a week, those days I eat half my "lunch" right after my work-out.

Obviously I'm sharing an anecdote but I mention it just because it echo's the research I mentioned and as a testimonial that it works for me. I eat an absurd amount of sugars and carbs but my total calories are restricted and I'm in fantastic shape.

[mixmastamyk]

True about calories at the lowest level. You can eat sugar and workout and feel hungry a lot of the time and stay trim, certainly not impossible... riding the blood-sugar roller-coaster every day, so to speak.

I eat some junk on the weekends myself, that's how I get perspective on drastic changes in my energy levels.

Or, instead you can switch into fat-burning mode and have a constant blood sugar and not feel hungry nor have to skip meals. Lots of good stuff too, eggs, spinach, olive oil, flax, etc. Doc says my bloodtest numbers some of the best he's seen.

Fad diets are suspect, but this isn't one of them. When was the last time in the wild you saw a chimpanzee or early human eating a loaf of bread, pasta, or cookies? Never, because they are man-made creations. The fad diet is the empty-carb diet pushed by the modern world, the results of which are obvious.

Humans have evolved over millions of years eating veggies, fruit, nuts, meat, etc.

I'm forming an idea, that there is nothing wrong with these two approaches. Rather there is a choice. Perhaps some of us prefer trading off in favor of tasty sweets, while some of us prefer stable blood sugar. You can live much longer than our poor ancestors with either approach. So, let's not bash the A- students on the other side because they're not perfect.

[aaxe]

> Just that the more sugar and starch eaten, the less time the body can stay in fat-burning mode

This is 100% bullshit.

[mixmastamyk]

Eagerly awaiting further erudite explanation...

[jacques_chester]

Firstly, the body is not a finite state machine. All the mechanisms of metabolism and there are a lot of them are, basically, active all the time. A great deal of complicated chemistry is underway, simultaneously, day and night. Including reactions whose effects cancel out, meaning that it is the balance of reactions that determines the system configuration.

(Yes! It's multivariate integral calculus, back from your youth to haunt you!)

Anyway, the second problem is that blood sugar in healthy individuals is very well regulated anyway. The blood sugar pathologies you see in obese individuals are usually pathologies of obesity, not the other way around.

The third problem is that carbohydrates, even simple ones, don't have a monopoly on short-term blood sugar effects. Insulin is usually identified as the primary regulator of blood sugar, but insulin is affected very strongly by protein as well as by carbohydrates. This is because insulin actually has a whole bunch of functions, only one of which is blood sugar regulation.

Biology is really complicated. It's the worst spaghetti code ever. It works, but there's no modularity, no information hiding, no clean APIs, everything is a global variable and there's not even the most basic concurrency controls. It's very hard to reason about.

But because it is so robust, it is easy to do thing A, get result B and attribute the results to factually incorrect theory Z9-gamma-pink-battleship.

[mixmastamyk]

You have an odd way of looking at things. ;) I happen to find the whole thing pretty amazing, the universe is beginning to understand itself.

Not to mention elegant in the way the human body runs perfectly on early-human food.

I'm not obese, and when eating sugar/starch I end up sleepy at times and starving a few hours later. Everyone knows it... moms have been telling us for decades if not centuries, not to give sugar to children.

Proteins/fats must be converted, meaning their glycemic index will be much lower. As such, a day or two after I substituted green-veggies & nuts for grains the difference was palpable.

I have not been stuffed or starving for over a month, lost my spare tire, and am loving it. Fits perfectly with everything I learned in chem, bio, and nutrition at uni. long before this became a movement. I don't think of this as FSM, rather differential equations such as these: http://17calculus.com/calc08-app-ccfluids.php

There are benefits to keeping blood sugar levels stable whether people want to believe it or not.

[magnusson]

Fat-burning stops when you consume fat, not just when you consume carbs.

Effects of an oral and intravenous fat load on adipose tissue and forearm lipid metabolism. http://www.ncbi.nlm.nih.gov/pubmed/9950782

"Six subjects were fasted overnight and were then given 40 g of triacylglycerol either orally or as an intravenous infusion over 4 h. Intracellular lipolysis (hormone-sensitive lipase action; HSL) was suppressed after both oral and intravenous fat loads (P < 0.001). Insulin, a major regulator of HSL activity, showed little change after either oral or intravenous fat load, suggesting that suppression of HSL action occurred independently of insulin."

[eightpersimmons]

This doesn't address what I think was one of the most interesting points in the article - weight gain is present even in lab animals with strictly monitored diets.

The implication being, of course, that this isn't the whole story, and we are doing ourselves a disservice by chalking up everything to diet.

(I don't mean to say you are wrong about this fact by any means - I'm not any kind of expert, and you sound very convincing.)

[mixmastamyk]

I was thinking about that myself and came up with the idea that perhaps their diet is changing.

I wouldn't be surprised if laboratory food was centralized around corporations just like human food. Meaning, I bet cheaper ingredients (more wheat/corn) have made their way into it over time. I can't imagine such peripheral industries not being affected.

[nwhitehead]

This is an interesting hypothesis. It wouldn't even have to be changing percentages of ingredients, it could simply be the result of increased agricultural efficiency and yields. 100 calories worth of corn feed is quite likely to be subtly different in composition today than decades ago.

[mixmastamyk]

Yes, pesticides and packaging are thought to be possible factors too.

[boneheadmed]

I think that what you're saying is most likely what is happening.

[boneheadmed]

I did read that point and find it perplexing. I would like to see hard data about that. For instance is the general diet for laboratory rats now the same as it was 50 years ago?

But also, if you have a look at my abstract, it does point to another potential cause of obesity and type 2 diabetes in humans (but naturally not the lab animals) - food addiction. The patients in this study were also successful (presumably) because they were actively involved in a 12 step program for food addiction.

On a personal note, I lost 30 lbs over 6 months by pretty much eliminating sucrose from my diet and also consuming a lower amount of carbohydrates (120 - 180 grams per day).

[glenra]

> I did read that point and find it perplexing.

The "fat virus" theory would perfectly explain it. If some of our co-evolved viruses and bacteria have been making us more prone to accumulate fat and it's contagious, the lab animals caught it too. So their metabolism slows down to allow them to accumulate weight on the same diet that used to be merely sufficient for sustenance.

On a personal note: I also lost 30 pounds over 6 months once. I did it by simply counting calories (hacker's diet). And I kept the weight off for about a year. But then I gained it all back and then some within the next few years. Most people can lose weight on most diets in the short term; the real trick is losing a significant amount of weight and keeping it off in the long term. Although some people manage to do it, it's not many. How to reliably lose weight and keep it off is still basically an unsolved problem.

[svdad]

No, it isn't. Unless you're saying you gained weight again while still eating the same diet, you solved the problem, you just failed at implementing the solution.

[glenra]

A diet people consistently can't keep to doesn't constitute a solution to the problem.

It's also worth noting that people who have gained a bunch of weight and lost it have a slower metabolism than people who stayed at the same weight. The Hacker's Diet - being based on calories in/calories out - did not account for this factor. The claim it made was that you could lose weight by keeping a calorie deficit for a while, then once you've lost enough weight you could stop the deficit, go back to basically eating at the level you did before and still stay at the new weight. Which doesn't work.

Dieting seems to work because your body takes a long while to adapt to new conditions. Eventually you get hungrier and less active; progress tends to stop and reverse whether or not you keep "trying".

Temporarily losing weight is "a solved problem". But losing weight without reducing metabolism and thereby making yourself more likely to gain weight in the future, is not.

[DanBC]

> But losing weight without reducing metabolism and thereby making yourself more likely to gain weight in the future, is not.

No, it is. Getting people to do it and stick to it is unsolved.

Lifestyle change, to reduce calories and restructure meals to include correct balance of proteins, carbohydrates and fats, and to raise awareness of when food is eaten and how many calories are being eaten, is tricky. But if people do it it works.

[colomon]

You know, if your algorithm worked on the first few test cases you threw at it but after that you kept on finding holes in it, you wouldn't say it had solved the problem, would you?

12 years ago, I lost 55 pounds in six months. All I had to do was carefully monitor everything I ate and burn 1000+ calories exercising six days a week.

Thing is, that was a solution that worked very well for me when I was self-employed 30-year-old single man. It has not worked at all for me as a 42-year-old married man with a child. I don't have the time for 90 minutes of exercise every day. There is always loads of food around I shouldn't be eating. I have vastly more stress in my life than I had then. And my body very definitely reacts differently to food than it used to.

What I'm trying to say is, I found a great hack for losing weight quickly back in the day. I did not find a solution to keep my weight down in the long term.

[enraged_camel]

>>You know, if your algorithm worked on the first few test cases you threw at it but after that you kept on finding holes in it, you wouldn't say it had solved the problem, would you?

The parent said he lost 30 pounds over 6 months. This is not a "test case." He implemented the solution effectively. What he ended up doing however was to change the input variables (literally) by increasing the amount he was eating. Therefore the solution he implemented failed, and he gained the weight right back.

[dublinben]

The long term solution to keeping your weight down is to eat at your maintenance level. If you do not eat more than your your Total Daily Energy Expenditure (TDEE), you simply will not gain weight. If you eat less than your TDEE, you will lose weight. This might not be easy, but it's pretty simple.

[DanBC]

> How to reliably lose weight and keep it off is still basically an unsolved problem.

No, it really isn't.

"Eat less calories than you burn". It's that simple. Even if we include various viruses and bacteria that help us lose weight or help us gain weight, and we include various disorders that help us lose weight or gain weight, the answer is still "Eat less calories".

Unless of course you're saying that getting people to change behaviour, for ever, is tricky. In which case I agree with you.

[jurassic]

If anyone is interested in trying this diet, there's a good support community at reddit.com/r/keto

[TeMPOraL]

I've lost 12 kg over 2 months of keto, so I endorse this :). Since then I returned to eating what I used to eat, but with less bread and pretty much 0 sugar (I got used to artificial sweetener and diet coke) and so far (4 months) I'm able to maintain my weight (with +/- 1kg variation).

One thing I noticed while on keto is that it reduced my appetite a bit.