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The Carbohydrate Hypothesis of Obesity: a Critical Examination


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There's no big conclusion here but a super fascinating discussion of the actual science behind whether carbohydrates and insulin cause obesity.

I think the real culprit is processed foods.

Not all carbs are bad, but processed carbs are particularly bad.

Carbohydrate consumption per se is not behind the obesity epidemic. However, once overweight or obesity is established, carbohydrate restriction can aid fat loss in some people. The mechanism by which this occurs is not totally clear, but there is no evidence that insulin plays a causal role in this process. Carbohydrate restriction spontaneously reduces calorie intake (as does fat restriction to a lesser extent), suggesting the possibility that it alters body fat homeostasis, but there is no compelling evidence that that happens due to a hormonal influence on fat tissue itself. The brain is the primary homeostatic regulator of fat mass, just as it homeostatically regulates blood pressure, breathing rate, and body temperature. This has been suspected since the early brain lesion studies of the 1940s and even before, and the discovery of leptin in 1994 cemented leptin's role as the main player in body fat homeostasis. In some cases, the setpoint around which the body defends these variables can be changed (e.g., hypertension, fever, and obesity). Research is ongoing to understand how this process works.

This is false:

"Carbohydrate restriction spontaneously reduces calorie intake (as does fat restriction to a lesser extent)..."

Carbohydrate and Proteins both convey approximately 4 calories per gram consumed, Fats convey 9 calories per gram:

Fat restriction would spontaneously reduce caloric intake to a GREATER extent than carbs...

I'm not sure if this was a typo or if the person simply doesn't know what the hell they're talking about... and after reading the post hoc ergo proptor hoc article I'm leaning toward the latter...

Perhaps the author believes that people eat fewer fat grams as a result of them being more caloric?

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