From the link Neckhammer posted above (kinda science-y for the bro-sci crowd I know, but well worth a read)
Ketogenic Diets, Cortisol, and Stress: Part I — Gluconeogenesis
One recent myth, prevalent in the Paleo Diet community, is that the keto diet is stressful to the body ¹. This idea arises from misunderstandings about cortisol — “the stress hormone”. There are two different arguments we know of, and this post will address the first one, the “gluconeogenesis requires cortisol” myth.
This myth comes from a mistaken chain of reasoning with three steps in it, only one of which is correct:
On a keto diet, because you get very little glucose from carbohydrate in your diet, your body makes its own glucose on demand, in a process called gluconeogenesis. (This is correct.)
Gluconeogenesis requires elevated cortisol. (This is not correct.)
Chronically elevated cortisol damages the body. (This is not precisely true. In a subsequent article in this series, we will explore the relationship between cortisol levels and health. Nonetheless, it makes no difference for this argument — because gluconeogenesis does not in fact require excess cortisol.)
Gluconeogenesis does not require high levels of cortisol.
When blood sugar begins to get low, glucagon — the primary hormone responsible for ensuring adequate blood sugar — is produced. This promotes gluconeogenesis, and it happens before blood sugar gets low enough to trigger increases in cortisol.
When blood sugar gets so low that excess cortisol is produced, it is also low enough that symptoms of hypoglycemia (“low blood sugar”) appear — anxiety, palpitations, hunger, sweating, irritability, tremor; or in more extreme cases, dizziness, tingling, blurred vision, difficulty in thinking, and faintness. So hypoglycemic signs are a good way to judge if cortisol is involved.
Since keto dieters do not normally appear to suffer from hypoglycemic episodes, especially when eating enough protein and not fasting for long periods (indeed, hypoglycemic episodes appear to be reduced by keto diets), it is unlikely that cortisol comes into play to regulate blood sugar for normal keto dieters.
On a keto diet, your body makes the modest amount of glucose it needs out of protein in a process called gluconeogenesis (GNG). There is a widely-held misconception that for GNG to occur, there must be high levels of the stress hormone cortisol in the blood. This mistake comes out of the fact that cortisol stimulates GNG. Therefore, it is reasoned, whenever you rely on GNG, your body has to produce and circulate more cortisol. This, however, is like arguing that since a reliable way to make people laugh is to tickle them, that every time you hear someone laughing it means they are being tickled. It turns out there are other ways to make people laugh, and there are other hormones that induce GNG.
The usual hormone to stimulate GNG is glucagon. Glucagon is produced when blood sugar gets low, and its primary function is to restore blood sugar to optimal levels. Cortisol levels rise when blood sugar reaches an even lower level. That is, the blood sugar threshold for cortisol production (55 mg/dL) is lower than the threshold for glucagon (65 mg/dL) ².
In fact, it turns out that the level of blood sugar that has to be reached to significantly increase cortisol is so low that clinical symptoms of hypoglycemia also start to appear at that level ³. Not only are reports of hypoglycemic episodes in studies of keto dieters rare, it has been known since at least 1936 that keto diets with adequate protein help prevent hypoglycemia ⁶.
GNG is stimulated by glucagon, and as long as the GNG response to glucagon is enough to restore blood sugar before it goes down to about 55mg/dL, cortisol will not be called upon to regulate blood sugar.
By the time blood sugar levels have gotten so low that cortisol is deployed to help fix it, hypoglycemic symptoms also appear.
Keto dieters don't appear to experience hypoglycemic symptoms (except in some cases involving inadequate protein or prolonged fasting). In fact keto diets, especially protein-adequate keto diets, have been used to reduce the occurrence of hypoglycemic episodes in susceptible people.
Therefore it is not true that because keto diets use GNG for blood sugar regulation, they cause stress to the body.
Well-behaved women rarely make history : Laurel Thatcher Ulrich
My New Primal Journal : http://www.marksdailyapple.com/forum...tml#post821642
My 1st Primal Journal (including travel journal of Africa) http://www.marksdailyapple.com/forum...back-to-Africa
Not sure what your source is...
Glucagon - New World EncyclopediaGlucagon is a catabolic (part of metabolism that breaks down larger molecules) protein hormone that works together with its anabolic counterpart, insulin, to regulate the levels of glucose in the bloodstream. It is produced by the alpha cells of the islets of Langerhans in the pancreas of vertebrates. Working to opposite effect from insulin, glucagon acts to increase blood sugar levels by stimulating the breakdown of liver glycogen to glucose (glycogenolysis), increasing release of glucose from the liver into the blood, preventing the liver from storing glucose, and increasing glucose formation in the liver from dietary protein (amino acids) and fats (Bender and Bender 2005; MedNet 2001). Glucagon also transiently paralyzes the muscles of the intestines.
Isulin and glucagon have a yin-yang relationship. Glucagon is a catabolic hormone - it breaks down muscle tissue. It works to fight hypoglycemia by destroying lean mass and breaking it down into glucose to combat hypoglycemia.
Glucagon is often deployed in levels of high stress - like when insulin and blood glucose drops too low. This in and of itself is a marker of stress. If you are constantly in a state of gluconeogenesis, you are constantly in a catabolic state.
This is where the logic falls apart. From your quote:
A good reference is Mark Sisson himself.On a keto diet, your body makes the modest amount of glucose it needs out of protein in a process called gluconeogenesis (GNG).
Your brain needs around 200g of glucose to function. According to Mark, on a low carb diet, you need around 120g due to modest ketone production and in "maximum ketosis" (whatever that is), you'd need at least 30g in theory.
The ironic part is, 200g of carbs (modest by the article's own admission) would give many low-carbers a panic attack. Even 30g is too much to keep most people in "max ketosis." I had to be <30g to produce any ketones according to test strips as a moderately active young male. Imagine what a sedentary female needs.
The reason why you don't see ketogenic dieting in the athletic community is because it is notoriously muscle wasting. And this is what annoys me about the average paleo. We are part of a community that is against processed food because they feel it reduces lean muscle mass, and they succumb to an eating plan that is notoriously lean-mass-destructive. Ladies and gentlemen, this is why we have a black eye in the fitness community.
Glucagon breaks down lean tissue to create glucose. If you are in ketosis, glucagon is necessary to break down lean tissue to make the rest of the glucose necessary for brain function that ketones cannot compensate for. I prefer to get my glucose from carbohydrate, not lean muscle mass. That was my only point.When blood sugar begins to get low, glucagon — the primary hormone responsible for ensuring adequate blood sugar — is produced. This promotes gluconeogenesis, and it happens before blood sugar gets low enough to trigger increases in cortisol.
Oh, I get it now! So any hormone that doesn't fit your current WOE is now a "stess" hormone...and since there is no agreed upon definition of such or at least without context you can use "stress hormone" with impunity. Seriously how is this any different from what you might consider the demonization of carbs/insulin? Your going to have to be far more specific i.e. concentration levels, peaks, time spent at various concentrations in response to ingestion....all those things you check for glucose intolerance and insulin level response are going to have to be studied and attributed to your so called "stress hormones" then your going to have to correlate those findings with ill health. Once you have that you will have to check those findings against a population of ketogenic dieters with a variety of athletic and lifestyle parameters. If you have that data please share!
Not really arguing for or against your carb intake. Really its just fine either way. I'm actually just trying to clear up the glucagon bit. So your saying a meal that has all protein and fat which inherently produces a glucagon release does not use that protein for any bit of the gluconeogenesis rather than breaking down lean mass?