From the man himself:
"Glucagon, insulin and ketogenesis:
The formation of KB's and utilization of fuel is ultimately controlled by
the circulating levels of insulin and glucagon. Insulin is a hormone
released from the pancreas in response to eating carbohydrates. Glucagon
is insulin's antagonistic hormone and is only present when insulin levels
fall to quite low levels. In the liver, high glucagon levels direct FFA
away from TG synthesis and towards beta-oxidation. Glucagon also activates
adipose tissue lipase which activates lipolysis. Glucagon's ketogenic and
lipolytic effects are inactivated by even small amounts of insulin. To
achieve sufficient glucagon concentrations for increased
ketogenesis/lipolysis, blood glucose levels must drop to around 50-60 mg/dl
and insulin must drop almost to zero. This drop in insulin can occur with
complete fasting, exercise, or by simply restricting carbohydrate intake to
below 30 grams per day. Within about 3 days of carbohydrate restriction,
blood glucose will fall below 60 mg/dl, insulin levels will drop to zero
and glucagon levels will increase causing an increase in KB formation.
With exercise training, ketogenesis should occur more quickly and ketosis
established. (2)
Establishment of ketosis, even in the short term, has the effect of
increasing the body's ability to utilize fat for fuel. After adaptation to
ketosis, there is a decrease in fasting RQ (an indicator of relative fuel
metabolism with lower values indication greater reliance on fat metabolism
versus carbohydrate metabolism) (7). Also, there is a decrease in glucose
oxidation during ketogenic diets as KB's are providing much of the body's
energy needs (18). Additionally, adaptation to a ketogenic diet increases
fat oxidation during exercise even in trained individuals (14, 17).
One point of contention regarding ketogenic diets is the supposed protein
sparing effect when compared to a eucaloric diet with a high carbohydrate
intake. Due to methodological differences, some studies have found a
decrease in protein utilization while others have found an increase (8).
However, available data seems to support the idea that ketosis spares
protein from being used for energy. Since there is essentially an
unlimited supply of fat which can be converted to ketones, and since
ketones can be used by all oxidative tissues, there should be little need
to oxidize protein to generate glucose through gluconeogenesis. There is
an obligatory protein requirement which must be met of about 30 grams per
day. And, to be safe, an intake of 60-75 grams of protein is recommended
(7).
Other effects of low carbohydrate diets
Additionally, a low carbohydrate intake will allow for overall greater
lipolysis and free glycerol release when compared to either high
carbohydrate or normal diets (7, 12). This is mediated in part by the lack
of insulin, which has a lipolysis blocking action even at low
concentrations as well as increases in other lipolytic hormones such as
growth hormone, glucagon, the catecholamines, and glucocorticoids. (7)
Additionally, growth hormone levels increase on low carb diets which will
further help to prevent the inevitable protein losses which occur when
calories are restricted (2, 7).
This help? I assumed you had this but you never know