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by throwaway_tech 2299 days ago
>excess protein is not converted to fat via GNG, but is used for protein synthesis, and increases lean body mass.

>In conclusion, after a high-protein diet, GNG was increased... https://www.cambridge.org/core/journals/british-journal-of-n...

2 comments

Just reading the abstract makes it pretty obvious.

> "A total of twenty-two healthy subjects (ten men and twelve women: age 23 (sem 1) years, BMI 22·1 (sem 0·5) kg/m2) received an isoenergetic high-protein (30/0/70 % of energy from protein/carbohydrate/fat) or normal-protein diet (12/55/33 % of energy from protein/carbohydrate/fat) for 1·5 d in a randomised cross-over design"

It wasn't the increase in protein that stimulated GNG. It was the reduction of carbs. Without sufficient dietary carbohydrate, the body must maintain minimum glucose levels via GNG.

GNG increases when in ketosis, but is still capped because ketones regulate the GNG process. That is the effect which was observed here. It says it right there in the synopsis:

"Glucose concentration was lower (4·09 (sem 0·10) v. 4·89 (sem 0·06) mmol/l, P < 0·001) and β-hydroxybutyrate concentration was higher (1349 (sem 139) v. 234 (sem 25) μmol/l, P < 0·001) after the high-protein compared with the normal-protein diet."

β-hydroxybutyrate is a ketone body.

Note that this contradicts your statements that GNG will kick you out of ketosis. It absolutely will not.

To repeat: GNG is constant, regulated by ketones, and its relative level is not driven by protein demand, but by glucose depletion.

>Note that this contradicts your statements that GNG will kick you out of ketosis. It absolutely will not.

Its really simple, eat nothing but chicken and/or turkey (high protein, low fat, no carb). You will not become keto adapted or fat adapted.

Alternatively enter into nutritional (dietary) ketosis with a high fat diet, then switch to chicken and/or turkey only (high protein, low fat, no carb) you will not remain in ketosis.

Do you disagree with that? Have you seen any study that shows fat/protein ratios are immaterial to nutritional ketosis?

Yes I disagree with that. Dietary fat is not required to enter ketosis. On a lean protein diet, you will indeed go into ketosis, and your body will start using its own fat reserves to produce ketones. However, the transition to ketosis will be more difficult.

In fact, the biggest mistake keto dieters make is to assume that "fat doesn't make you fat". That's just wrong. On any high-fat keto diet you will burn dietary fat before burning your own fat. If weight lost is one's goal, it is essential to limit fat intake to moderate levels, just enough to keep you sated, so that the body is using its own fat reserves.

I'm not aware of any dietary fat requirement to enter or maintain ketosis. I've talked to others that mention a protein/fat ratio but I've not see any literature about it. Citation appreciated.

A low carb and low fat diet is unhealthy for lean people because fat/fatty acids/etc is required for a whole lot of synthesis.