If Gary Taubes's carbohydrate/insulin hypothesis of obesity is correct, everyone would lose more weight on low-carbohydrate diets than on high-carbohydrate diets. This isn't the case, therefore Gary Taubes's hypothesis is not correct.
Although insulin is involved, it has nothing to do with "Hormonal clogs" or "Insulin fairies".
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| The Aragon Insulin Fairy |
The Energy Balance Equation
Change in Body Stores = Energy in - Energy out, where...
Energy in = Energy entering mouth - Energy exiting anus, and...
Energy out = BMR/RMR + TEF + TEA + SPA/NEAT
See The Energy Balance Equation to find out what the above terms mean.
People with Insulin Resistance (IR), Impaired Glucose Tolerance (IGT) & Type 2 Diabetes (T2DM) have excessive insulin secretion in response to meals (postprandial hyperinsulinaemia). See Hyperinsulinaemia and Insulin Resistance - An Engineer's Perspective.
People with Insulin Resistance (IR), Impaired Glucose Tolerance (IGT) & Type 2 Diabetes (T2DM) also have impaired/no 1st phase insulin response to a sudden rise in blood glucose level. This introduces a time-lag into the negative feed-back (NFB) loop that regulates blood glucose level. If the input rise-time is less than the time-lag in a NFB loop, the output of the NFB loop overshoots. This is standard NFB loop behaviour. See Control of overshoot for more information.
1. On a high-refined-carbohydrate or high-GL diet, blood glucose level rises rapidly, with a rise-time that's less than the time-lag in the blood glucose regulation NFB loop. Insulin secretion from the pancreas overshoots in a positive direction. The resulting postprandial hyperinsulinaemia results in down-regulation of insulin receptors in the brain, which reduces insulin action in the brain. When the insulin level eventually falls to normal a few hours later, the brain interprets a normal insulin level as hypoinsulinaemia. Hypoinsulinaemia results in ravenous hunger, as insulin is a short-term satiety/satiation hormone in the brain (leptin is a long-term satiety/satiation hormone in the brain). Ravenous hunger results in over-eating. Energy in increases. Postprandial hyperinsulinaemia also results in postprandial sleepiness. Energy out decreases. ∴ Body stores increase. There are also accusations of gluttony & sloth!
2. On a low-carbohydrate or low-GL diet, there are small fluctuations in blood glucose & insulin levels. There is no ravenous hunger. There is much less/no over-eating. Energy in decreases. There is no massive postprandial hyperinsulinaemia. There is much less/no postprandial sleepiness. Energy out increases. ∴ Body stores decrease.
In addition, there is a loss of water weight due to a loss of liver & muscle glycogen. This can be ~2kg in one day (it varies from person to person). Kidneys can increase their output of urine for hormonal reasons. This can increase water weight loss to ~5kg. See Why counting Calories and weighing yourself regularly can be a waste of time.
There are also other hormones involved. For a Facebook discussion with James Krieger that led to the updating of this post, see https://www.facebook.com/james.krieger1/posts/10153228943648587
In Metabolic Ward studies, food intake is tightly controlled, so postprandial hunger doesn't result in over-eating. Energy expenditure is also controlled, so postprandial sleepiness doesn't significantly affect energy expenditure. This is why varying Fat:Carb ratios (with Protein held constant) makes no significant difference to weight in a Metabolic Ward. See Energy intake required to maintain body weight is not affected by wide variation in diet composition.
Inter-personal variations in postprandial hyperinsulinaemia, postprandial sleepiness & energy out explain the inter-personal variations in weight gain seen under hypercaloric conditions. See Bray et al shows that a calorie *is* a calorie (where weight change is concerned).
Insulin Resistance can be fixed. See Insulin Resistance: Solutions to problems.
Type 2 Diabetes can also be fixed. See Reversing type 2 diabetes, the lecture explaining T2D progression, and how to treat it.
Aim to fix the problem. If it's impossible to fix the problem, a low-carbohydrate diet as an adjunct to medication is fine.
