There is at least one person in these comments extolling the virtues of keto viz a viz quick weight loss without exercise.

I don't know what a normal low fat diet is, but the overruling factor in weight loss/gain is the ratio of work (exercise) to energy input (calories).

Physics, years of evidence and common sense down voted on HN where solyent is seen as a good thing.

The physics is that exercise burns so few calories it's not worthwhile from a weight loss point of view.

Where have those physics been documented?

I want to see the same person:

    'immobile
    'sitting most of the time, with short commutes and shopping trips
    'intensely exercising 1 hr a day
    'actively working out throughout the day

while maintaining their current diet and weight.

These aren't independent variables. The point is that a half an hour run only burns around 300-400 calories, a deficit which could more easily be accomplished by diet. Also, it's possible that the run would increase your appetite.

The point isn't that exercise _can't_ work, it's that aiming for dietary changes has a higher average ROI than exercise.

"these"? I don't know what that refers to.

No one has argued that there is a lower than average ROI (you get paid for not eating?) from exercise.

It's not physics, it's biochemistry.

But it's more complicated than that. Genetics cause one's predisposition as to how responsive a person is to cardio; see the University of Bath study and/or Michael Mosley's "The Truth About Exercise".

>but the overruling factor in weight loss/gain is the ratio of work (exercise) to energy input (calories).

I don't think you are off, but the key is not weight loss/gain...the key is healthy weight loss/gain and that has everything to do with what you consume.

Calories_out = Calories_in - Calories_stored.

Caloric source matters, your body does different things with different sources.

Your metabolism will be reduced by reducing calories in. They are not independent variables.

He said eat normal and healthy, not eat low fat; low fat is also a fad diet. And yes, keto is a fad diet with no empirical evidence to support its claims, testimonials are not evidence. There was actually a recent scientific study done and it found keto claims lacking. I've done keto, I'm well aware of what it is, but the weight loss is far more likely to come from eating less than from not eating carbs because it's fucking hard to consume a lot of calories once you cut out carbs so most people on a keto diet are actually on a calorie restricted diet as well which is why they're losing weight.

You want to lose weight, don't eat anything in a box, buy fresh whole food, plenty of veggies and fruits, and meat, cut out sugar, and it'll happen automatically. We're fat because of processed foods that have far too many calories in far too small a bulk that makes overeating so easy you don't even know you're doing it.

That is wrong, the ketogenic diet is prescribed by doctors to patients suffering from seizures and it works. There are long term studies and the NYTimes has been reporting about this since the 90s. http://www.nytimes.com/2010/11/21/magazine/21Epilepsy-t.html

Everyone picks a diet. If you just randomly eat anything thats available to you, in the developed world, you are most likely significantly overweight and at very high risk of diabetes. With rare exceptions, most fad diets will leave you better off than with no guidance whatsoever. Sometimes pointing someone in the wrong direction is better than them walking off a cliff.

Diet science is definitely progressing and getting better. We knew the basics, like what happened when you didn't get enough vitamin C, but the rest of the details are finally getting fleshed out and accepted by mainstream science.

That said, people following the ketogenic diet need to be doing it correctly and under a doctor's supervision. If you half ass it you can end up just eating a shitload of bad fats and miss nutrients while not actually being in ketosis. That will not lead to a good outcome.

Your argument is flawed, doctors prescribe lots of things that aren't good for you because for that person, they're better than the alternative, chemo for example. That something is done by doctors does not make it good.

> but the rest of the details are finally getting fleshed out and accepted by mainstream science.

Uh, no, mainstream science is the only one doing the fleshing out; you're implication that they're behind and only now accepting what diet science already knows is anti-intellectual bunk. If it isn't mainstream science, it isn't science.

"Mainstream" science is regularly hijacked by corporate and other interests. Dietary science is one area that was strongly influenced by producers of refined carbohydrates.

Prescribing it for epilepsy doesn't necessarily make it a healthy diet for your average individual as you are looking for different effect from the diet.

You're also neglecting another benefit of keto for maintaining a low-caloric intake, it encourages you to eat fat. Fat takes a substantially longer amount of time for the stomach to process, meaning you feel satiated for a longer period of time. Whenever I eat carbs I try to supplement them with a good amount of fat to avoid this, yesterday I had a 300cal snack of 5 saltines topped with roughly 3tbsp of peanut butter and felt great for 4 hours, meanwhile this morning I had a single 240cal croissant for breakfast at 8:30 and have been dying for lunch since 10:00AM.

Normal and healthy diets are balanced; most people's diets are excessively heavy in carbs, so no, I didn't neglect that at all. People should eat less carbs and more fat until they're somewhat of a balance, going in either direction by cutting out one or the other is not eating healthy. Keeping your body in long term ketosis is neither healthy nor particularly pleasant. Yea, eating a pure carb snack is going to make you crash, so don't do that, eat something balanced and made of real whole food, not processed crap.

The tricky part is that it isn't clear what "balanced" means. Our bodies can survive on vastly different allocations of the three macronutrients. Carbohydrates are not required at all to my knowledge, while some amino acids and fatty acids are essential and cannot be synthesized from other foodstuffs.

Its possible to get most of your calories from carbohydrates, protein, or fat. The question is what is the right balance for optimum health? How much does this value change across different people (and possibly at different stages of life)? If you have epilepsy then a ketogenic diet might well be best. How about for other people?

What macronutient profile is "balanced"? What do you even base it on? Should it be 33% of each? Should we eat protein and fat in just a little in excess of what we need (to get the essential fatty acids and amino acids) and get the rest from carbohydrates? I don't think we have clear answers to those questions yet. Although, I think we have ruled out some diets as unhealthy (e.g. eating a lot of refined carbohydrates can cause diabetes). Since eating too many refined carbohydrates is bad does that rule them out as a primary calorie source? Probably not, but we need more research.

Personal Note: I've eaten a low carb, high fat, moderate protein diet for about 4 years. All my blood markers (cholesterol, triglycerides, etc) have improved significantly over that time period. Additionally, I used to get incredibly hungry all the time and feel bad if a meal was delayed. Now I can go much longer without eating and still feel well.

You don't have to be able to define balance, to point out unbalanced, and any diet largely cutting out one of the 3 is unbalanced.

> I've eaten a low carb, high fat, moderate protein diet for about 4 years. All my blood markers (cholesterol, triglycerides, etc) have improved significantly over that time period.

That's like saying I've been smoking for 4 years and I don't have cancer so smoking must not have any long term adverse effects; bad logic and insufficient sample size.

> You don't have to be able to define balance, to point out unbalanced

Yes, you actually have to be able to define what range of mixes counts as "balanced" before you can label anything as outside of that range. (And, moreover, if you want to credibly assign significance to that label, you probably also need to be able to provide evidence that your definition of "balanced" corresponds to a range outside of which there are serious negative consequences.)

> Yes, you actually have to be able to define what range of mixes counts as "balanced" before you can label anything as outside of that range.

No, you don't; for example, eliminating one is not balanced now matter what numbers you assign to balance.

It's unbelievable what kind of hive mind exists behind this anecdotal unscientific community.

Absolutely every thread on fat, sugar is filled with huge amounts of anecdotal evidence that is entirely worthless and delusional.

Fat people comment that they've lost weight by planning their diets more carefully (what a luck that it was keto), what a surprise.

I'm aware that being overweight is a huge issue in developed world and that most people easily lose weights on restrictive diets but it's all a fad.

"plenty of veggies and fruits" "cut out sugar"

You can't do both.

checkout studies on fructose/glucose in a glass that is consumed, and the equivalent in fruits.

good thing that the physical reaction isn't equivalent despite the fact that calorical intake of that sugar is the same.

it's a huge shame not to consume fiber, or berries, or other fruits.

fruits were made by plants to prolong the life of the consumer, it's absolutely impossible to overdose on bananas if you aren't deliberately consuming huge amounts and aren't prepared to sit for hours on the bathroom.

Every digestable carb will turn into glucose eventually, all that matters is how fast this happens because you want to minimize time spent at high blood glucose levels.

Sugars generally digest faster than starches but this is not always true. Oranges (as in the whole fruit with its structure and fiber intact) raise blood glucose more slowly than potatoes, even though oranges are mostly sugar and potatoes are mostly starch.

This also means that slowly eaten sugar is healthier than quickly devoured complex carbs (if dental health is ignored). E.g. eating 50g carbs worth of candy steadily over 4 hours will result in stabler blood glucose than devouring 50g carbs worth of rice in 5 mins.

On a keto diet you can still consume a good amount of fiber (in the form of green veggies or supplements) and a serving or two of berries. Most other fruits contain too much sugar though.

To the original point, if you consume fruit you're not really cutting out "sugar". The OP probably means added sugar.

Psyllium fiber is your friend. It even adds a nice texture to eggs and such.

> You can't do both.

Yes you can, because unless you're being obtuse, I'm obviously talking about processed white sugar, not fructose found in real food.

"processed white sugar" is half fructose.

Yes, but it's also not diluted with a ton of fiber like fruit; don't be obtuse.