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This series of blog posts is a fascinating read into conjectured factors behind the obesity epidemic. I wish the author had continued their rigor in reasoning
by Pyramus 5y ago
This series of blog posts is a fascinating read into conjectured factors behind the obesity epidemic.
I wish the author had continued their rigor in reasoning throughout the two blog posts. Step by step the author is lured into proving a single factor explains the rise in obesity. That maybe a futile attempt from the outset.
To make an example, the author notes, correctly and to the point,
> "Calories are involved in the math but it’s not as simple as “weight gain = calories in – calories out”."
but then moves on to claim that "X provides evidence against CICO" when in fact the article cites numerous examples where an increase/decrease in calories results in a (short-term) increase/decrease in body weight. So what the author really meant was "X provides evidence against CICO as the single factor".
I'm not an expert in nutrition science but it seems very unlikely that a single factor (sugar! trans-fats! exercise! genetics!) will explain a real-world, highly non-linear phenomenon. I personally find the paragraphs where the interactions of factors are discussed the weakest and least convincing.
That is not to say the article is excellent and hammers home two very important points: Firstly the idea of the lipostat and as a result a short and a long-term time scale ('system') for body weight gain/loss. Secondly that factors relevant on one time scale may not be relevant to the other time scale. And of course that there is still a lot we simply don't understand (yet).
- sdenton4 5y agoThe short term overeating studies produce what we might call highly nonlinear results, which also undermines CICO (which is a linear equation). It's pretty obvious the body has other ways to dump exceeds calories than turning them into fat stores. Those studies, and the obvious tendency of diets to fail in the long term, are strong support for some kind of lipostat system, to my mind. Others have mentioned gut biomes... My uneducated guess is plastics or some other chemical that was introduced into industrial use in the 20th century. The cross species effect (lab and zoo animals getting father on the same controlled diets) is also a really big clue that were dealing with a molecule. And, as with lead poisoning from gasoline, perhaps a hard to pinpoint one due to prevalence.
- msteffen 5y agoMy interpretation was: "what is responsible for the inflection point that occurred in 1980?" Perhaps it's still not a single factor (which, I agree, would make a lot of sense) but IIUC that does raise the question of why there seems to be a single inflection point.
- ajuc 5y agoDunno the relationship seems pretty straightforward to me: https://live.staticflickr.com/65535/51308115221_02f244737d_o.png https://live.staticflickr.com/65535/51308115221_02f244737d_o... There is certainly some diminishing returns effect but it seems much less important than kcal in-kcal out.