Quote from Lyle McDonald - The Ketogenic Diet:
-To briefly recap, during the first weeks of ketosis, approximately 75 grams of glucose must
be produced (the other 18 grams of glucose coming from the conversion of glycerol to glucose) to
satisfy the brainís requirements of ~100 grams of glucose per day. After approximately 3 weeks
of ketosis, the brainís glucose requirements drop to approximately 40 grams of glucose. Of this,
18 grams are derived from the conversion of glycerol, leaving 25 grams of glucose to be made
Since 58% of all dietary protein will appear in the bloodstream as glucose (3), we can
determine how much dietary protein is required by looking at different protein intakes and how
much glucose is produced.
Protein intake and grams of glucose produced *
Protein intake (grams) converted into Glucose (grams)
* Assuming a 58% conversion rate
Summery: dieters should consume zero Carbs on 150g protein diet since protein will provide 87g glucose by process called gluconeogenesis and other glucose will come from fat burning or you should lower protein intake and increase glucose intake from food.