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by cpymchn 3160 days ago
"keto pseudoscience" is loaded phrasing for a mechanism that has been understood and uncontroversial for 200 years.

If you are unfamiliar... the core insight is that obesity is an endocrine disorder; your hormones — not your caloric intake nor the amount you exercise — is the primary reason you gain or lose fat.

Here is a short explanation as to why this is:

* [enzymes] whether you store fat or not is determined by enzymes — specifically hormone sensitive lipase (HSL) and lipoprotein lipase (LPL)

* [hormones] production and inhibition of those enzymes is controlled by your hormones — including insulin, adrenaline, cortisol, estrogen and others.

* [diet] the easiest way to control your insulin levels is to keep your blood sugar low; the easiest way to control blood sugar is to eliminate carbs from your diet.

As I mentioned above... this can be simplified as...

No carbs —> suppressed insulin —> maximum HSL production.

'limiting the caloric intake' -- as you suggest -- is a blind alley when discussing this mechanism. It is a necessary but not a sufficient condition to lose weight. Your body won't draw on your fat reserves if it doesn't have to. i.e. it will happily extract the energy it needs from your gut all day long, provided your gut is full. That means you are partially correct; if LPL is low and if you are in a deficit then the body will draw down on your reserves and you will lose weight. But the opposite isn't true. If LPL is high, irrespective of your deficit or your willpower, then you won't lose weight. Conversely 'eating too much' isn't a diabetes risk... provided your hormones are in order.

If you have any sources that contradict the endocrine hypothesis, I would be keen to see them.

1 comments

> "keto pseudoscience" is loaded phrasing for a mechanism that has been understood and uncontroversial for 200 years.

Certainly not 200 years, and also certainly not "understood and uncontroversial". Atkins/keto goes against the conventional science of dieting from the 20th and 21st century because it doesn't follow the caloric intake affecting weight loss premise (though it can have that effect, like almost every diets can). It goes against the convention that saturated fats are unhealthy, and should be severely limited. Finally, we should remember that transfats were only in recent decades found unhealthy, mostly due to research in 00s by M. Katan. Your Atkins diet during its hype in 70s didn't exclude transfats.

> not your caloric intake nor the amount you exercise

I didn't claim the amount one exercises significantly matters in weight loss. In fact, I wrote throughout the thread that muscles increase weight.

However, having more slightly more muscles than the default 9 to 5 job (lack of muscles) helps with doing tasks like grabbing your bicycle to do a grocery, assembling an Ikea wardrobe, carry your toddler around, that type of activity. Being fit allows endurance. Both are arguably useful motivators.

The Atkins hype is recent (and the keto hype is more recent), not 200 years old. Its also not established by our governments (the equivalents of NHS, Voedingscentrum, etc).

Voedingscentrum has this to say in summary: "Het Atkins-dieet levert gewichtsverlies op, omdat de voeding in totaal minder calorieën bevat. Uiteindelijk gaat het erom de gezondheidswinst die dit oplevert vast te houden met een gezond, gevarieerd en volwaardig eetpatroon.

Diabetes-patiënten en mensen met een gestoorde nierfunctie kunnen dit dieet beter alleen volgen in overleg met hun arts en onder begeleiding van een diëtist." [1]

Which boils down to: "The Atkins diet achieves weight loss because the diet contains a total of less calories. Ultimately, it is about retaining the health gain that results in a healthy, varied and full-bodied eating pattern.

Diabetes patients and people with impaired renal function are better off only following this diet in consultation with their physician and under the guidance of a dietitian."

Compared with various other diets they're not even that negative about Atkins. Many alternatives are worse established.

If you got any sources where government organizations like the ones I mentioned recommended 200 years ago the Atkins or keto diet I'd love to read about that. Or perhaps sources where they actively recommend it to this day, including the theory behind it. Any government health service sources supporting it, also welcome. The burden of proof lies at you.

And of course there are tons upon tons of articles which suggest Atkins/keto don't work, complete with test subjects losing weight at start, finding diet not practical, and a yo-yo effect. Here's a quote from one of the many [2]: "[...] These observations led Sacks et al. to conclude that behavioral factors rather than macronutrient composition are the main influences on weight loss [...]" Recommend reading entire article.

[1] http://www.voedingscentrum.nl/encyclopedie/verzadigd-vet.asp...

[2] http://www.nejm.org/doi/full/10.1056/NEJMe0810291

Small point first… eating the same amount but exercising more equals a caloric deficit in the same way that exercising the same amount but eating less does. I am not following your point about muscles specifically but I think we can let that go provided you agree that being in a caloric deficit needn’t mean you eat fewer calories. That is all I was trying to say regarding exercise.

Second point… confusion is not the same as controversy. Even though people might be confused how the mechanisms and pathways work doesn’t mean they are controversial. Hormones dictate weight gain and weight loss. See pregnancy or puberty or menopause. (You even mentioned Thyroidism.) It’s not controversial. Calling it pseudoscience seems over the top. See the green house effect (first argued in 1824) for an analog.

Third point… my claims pertain to the biology not to the marketing behind certain diets. I don’t believe that the atkins diet is ketogenic… nor do I think the Voedingscentrum is correct in saying the diet has a ‘varied and full-bodied eating pattern’, but I also don’t care. As you say… it is hype. But if your counter-examples have no explanatory power, then they are just as worthless. More on this below. In the very least don’t equate the hormone hypothesis with an endorsement for Atkins.

Fourth point… I concede that my rhetoric is not iron clad. Since science is a process and certainty is always a question… it is hard to ever win an argument about this stuff… as Katan points out doing double-blind studies is near impossible so that makes claims in nutrition science doubly fraught. Having admitted that… I stand by my statement that the hormone hypothesis is not controversial. Yes the lipid hypothesis had sway in American culture in the mid 20th century but evidence to back it up was never produced. If any controversy existed, I would say it lay with the lipid hypothesis not with the endocrine one.

As to the bonfides for sugar induced obesity I would point to Jean Anthelme Brilliat-Savarin (writing in 1825), Alfred Moore (writing in 1860), John Harvey (writing in 1861) , and William Banting (1863). Their accounts were accepted by medical schools in the US and the UK, with varied levels of understanding, through to the 20th century… where Thomas Cleave and John Yudkin were their antecedents. Does that make my 200 year claim iron clad? Not really but I think it is good enough for arguments sake.

Last point… you haven’t made a case for an alternative to the hormone hypothesis. The links you included don’t do it. Your examples don’t do it. The Katan article doesn’t say that low carb doesn’t work… let alone provide an alternative mechanism for losing weight. As I wrote above… caloric reduction is a associated with instances of losing weight… but it doesnt CAUSE you to lose weight. Hormones do.