Waking At 3 Each Morning

[Colin Nordstrom]

Starch to me is genetic and gut specific. Asians have the genetics to handle rice. I do awful with rice. I agree with RP that starch is a bad idea if gut-compromised. I do poorly with starch if I get sedentary. If I eat starch post-exercise, I'm fine (maybe because of increased glut4 rising to the cell surface?). My gut also functions better if I'm exerting myself. I think any recommendations are sub-optimal if exercise isn't incorporated into the equation. If you can throw down a ton of starch/sugar without exercise, hats off to your genetics, but I can't do it (and I would never recommend it). Again, it all comes back to sleep quality, thyroid function, and stress levels. If those are out of whack, you ain't going to tolerate any diet.

 

[Colin Nordstrom]

@James IV, what's that other thread titled?

 

[DuggaDugga]

Thanks for clarifying your stance. James seems to be emphasizing the nighttime benefits of cortisol. I have no knowledge of that. My diet experience correlates well with his experience. What I do understand is how cortisol is directly linked to our circadian rhythms. I am deeply interested in the back and forth tug of war between cortisol and insulin. If too much insulin is in the picture, you can't release and burn fat stores; if too much cortisol is in the picture, your thyroid can't function. Whereas James is promoting this nighttime cortisol benefit, I do not. I promote exercise's beneficial role in insulin/glut4 response, and the subsequent release of adrenaline/cortisol to burn fat stores. Maybe we disagree on what should be eaten later in the day. I think it should be fat. However, if someone gets great sleep with late night carbs, great. The moral of the story is to get deep, restful sleep (however that happens through self-experimentation) so that you can function optimally.

Cortisol/adrenaline are excitatory in nature, so I don't believe that you would want them elevated at night to help you sleep. Cortisol does indeed rise in the morning. I think it's primarily due to the ~8 hour fasting of sleep, but I suppose it could be a built-in mechanism to wake us. When people are not wanting to get out of bed, I don't think it's due to cortisol deficiency, but rather serotonin/histamine mediating torpor. I think it's also good to consider melatonin and hormones that increase photo-sensitization, as they probably play a role in our waking as well. Surely it's a complicated thing.

I happen to agree with Ray on exercise, which is basically it's not necessary if one lives a stimulating life, reading, walking in nature, meeting new people, being creative. Our culture has a tendency to think of "burning calories" from physical exercise as the only way to lose weight, counting the calories they've eaten, and then estimating how much they burned on their 5 mile run to do back-of-envelope calculations. The thing is that we're all burning through our energy reserves at all times to satisfy every physiological need. You and I are utilizing energy creating these posts. Our bodies are utilizing energy to synthesize testosterone, detoxifying us of estrogen, collecting information from our retina and synthesizing vision/perspective of the world, etc, etc, etc. The living state is a constant battle with the second law of thermodynamics. We are losing energy and cohesiveness at all times. We are overcoming that energy deficit by oxidizing NADH, regenerating ATP, maintaining energy, maintaining function, maintaining structure. I think that is the living state, a flow of electrons. . . I digress.

Fat at night could have benefits. It's certainly a very dense source of energy. A spoonful of honey and a glass of milk is my go-to combo. But that's me.

 

[James IV]

Cortisol/adrenaline are excitatory in nature, so I don't believe that you would want them elevated at night to help you sleep. Cortisol does indeed rise in the morning. I think it's primarily due to the ~8 hour fasting of sleep, but I suppose it could be a built-in mechanism to wake us. When people are not wanting to get out of bed, I don't think it's due to cortisol deficiency, but rather serotonin/histamine mediating torpor. I think it's also good to consider melatonin and hormones that increase photo-sensitization, as they probably play a role in our waking as well. Surely it's a complicated thing.

I happen to agree with Ray on exercise, which is basically it's not necessary if one lives a stimulating life, reading, walking in nature, meeting new people, being creative. Our culture has a tendency to think of "burning calories" from physical exercise as the only way to lose weight, counting the calories they've eaten, and then estimating how much they burned on their 5 mile run to do back-of-envelope calculations. The thing is that we're all burning through our energy reserves at all times to satisfy every physiological need. You and I are utilizing energy creating these posts. Our bodies are utilizing energy to synthesize testosterone, detoxifying us of estrogen, collecting information from our retina and synthesizing vision/perspective of the world, etc, etc, etc. The living state is a constant battle with the second law of thermodynamics. We are losing energy and cohesiveness at all times. We are overcoming that energy deficit by oxidizing NADH, regenerating ATP, maintaining energy, maintaining function, maintaining structure. I think that is the living state, a flow of electrons. . . I digress.

Fat at night could have benefits. It's certainly a very dense source of energy. A spoonful of honey and a glass of milk is my go-to combo. But that's me.

All good points. So do you prefer sugar to starch as a carbohydrate source?

 

[James IV]

Starch to me is genetic and gut specific. Asians have the genetics to handle rice. I do awful with rice. I agree with RP that starch is a bad idea if gut-compromised. I do poorly with starch if I get sedentary. If I eat starch post-exercise, I'm fine (maybe because of increased glut4 rising to the cell surface?). My gut also functions better if I'm exerting myself. I think any recommendations are sub-optimal if exercise isn't incorporated into the equation. If you can throw down a ton of starch/sugar without exercise, hats off to your genetics, but I can't do it (and I would never recommend it). Again, it all comes back to sleep quality, thyroid function, and stress levels. If those are out of whack, you ain't going to tolerate any diet.

Very similar to my thoughts and experiences. Thank you for sharing.

Edit* the gboldeuv (sp?) q and a thread was the thread I was referring to.

 

[Colin Nordstrom]

I think the CICO theory is way flawed and the basis of many people's problems. I don't exercise to lose weight (though that is a consequence); I exercise because it shakes my body up through hormesis. Chronic/steady state exercise is a cortisol problem waiting to happen. I'm talking about resistance training/HIIT that is done only in short periods. Can a walk in the woods be just as effective? absolutely. Again, I go back to self-experimentation. Anybody that pushes their one size fits all dogma is selling something, and it's not health. For me, my creative juices flow after I do a short, intense workout (and get a good night sleep).

 

[James IV]

What issues do you wrestle with in regards to starch vs sugar? I've not been convinced by any of the anti-starch arguments.

Mostly the issue of digestablity, and appropriateness to human physiology. I lean toward fruit, for a number of reasons, however, fructose does inteed seem to be a problem for many modern people. Although, i often wonder if it's something besides the fructose when concerning fruit.

 

[DuggaDugga]

All good info. Maybe I didn't explain myself very clearly, but I didn't mean to come across as promoting cortisol. I was simply stating that elevation of cortisol is inevitable if you observe the circadian rythm of hormones. And I'm not sure trying to stifle that is necessarily a good thing. I think eating a large portion of carbohydrate at night, before sleep, may disrupt this cycle, and lead to poor sleep. So maybe pushing carbohydrates earlier in the day, with a bit more of fat being eaten in the evening, may be benificial if you are having sleep problems. I don't claim this is true across the board, but I've seen it very often.

I'm not promoting a low carb diet. I think sufficient carbs are very important. However, I also don't believe everyone needs to be in a high carb diet. You can read some of the stories of folks that destroyed themselves on a low fat high carb diet in the other thread going right now.

I hope that's more clear.

To @DuggaDugga. You are obviously an intelligent fellow. Out of curiosity, what are your views on starches vs sugars? This is the only point I still go back and forth on, and more input is always appreciated.

Thank you.

I agree that the ability to synthesize cortisol in the right circumstance is beneficial, like histamine, adrenaline, serotonin, estrogen; if the body has a legitimate need for it, then we would want to allow it to conduct it for survival (rather than suppress it with pharmaceuticals or anti-metabolic foods). I definitely would not seek to cause those responses for no reason though, and would instead seek a lifestyle that minimizes the need for those short-term-protective stress responses.

I'm not anti-starch but I eat them sparingly. Potatoes, rice, grains have a very high glycemic index, meaning they cause massive insulin spikes. Sucrose requires a smaller, buffered insulin response. I was a partying heavy-drinker for my adolescence and 20's, so my liver was totally shot when I found out about Ray. I had such a hard time maintaining hepatic glycogen once my metabolism increased so I had to eat fruit hourly to not get stressed. Slowly but surely things rectified themselves and now I have a much more constant blood sugar and overall disposition. Starches are probably best consumed well-cooked and with saturated fat to buffer the insulin response. Potatoes just taste better with butter anyways.

Eating too much/energy overload is a stressor in and of itself. I think when people suddenly go high-carb in response to learning about Ray they force themselves to do things like guzzle OJ even when they're not hungry/thirsty. Ultimately we need to be aware of and respond to our cravings to natural foods. I do agree with you that it's not a one-size-fits-all thing. There's infinitely more to each one of us that we can possibly communicate over this forum.

 

[raypeatclips]

Mostly the issue of digestablity, and appropriateness to human physiology. I lean toward fruit, for a number of reasons, however, fructose does inteed seem to be a problem for many modern people. Although, i often wonder if it's something besides the fructose when concerning fruit.

In an email conversation I had with Ray, he said that some fruit picked in the conditions it is, will never be fully ripe no matter what you do. I had big issues with finding "good" fruit when I tried the high sugar approach.

 

[James IV]

In an email conversation I had with Ray, he said that some fruit picked in the conditions it is, will never be fully ripe no matter what you do. I had big issues with finding "good" fruit when I tried the high sugar approach.

Yes. Frozen and canned fruit seem to be much more likely to be picked ripe.

 

[Mito]

I was a partying heavy-drinker for my adolescence and 20's, so my liver was totally shot when I found out about Ray.

How long did it take to repair your liver? Did you do anything specific to improve it or was it just diet/lifestyle changes?

 

[Regina]

I agree that the ability to synthesize cortisol in the right circumstance is beneficial, like histamine, adrenaline, serotonin, estrogen; if the body has a legitimate need for it, then we would want to allow it to conduct it for survival (rather than suppress it with pharmaceuticals or anti-metabolic foods). I definitely would not seek to cause those responses for no reason though, and would instead seek a lifestyle that minimizes the need for those short-term-protective stress responses.

I'm not anti-starch but I eat them sparingly. Potatoes, rice, grains have a very high glycemic index, meaning they cause massive insulin spikes. Sucrose requires a smaller, buffered insulin response. I was a partying heavy-drinker for my adolescence and 20's, so my liver was totally shot when I found out about Ray. I had such a hard time maintaining hepatic glycogen once my metabolism increased so I had to eat fruit hourly to not get stressed. Slowly but surely things rectified themselves and now I have a much more constant blood sugar and overall disposition. Starches are probably best consumed well-cooked and with saturated fat to buffer the insulin response. Potatoes just taste better with butter anyways.

Eating too much/energy overload is a stressor in and of itself. I think when people suddenly go high-carb in response to learning about Ray they force themselves to do things like guzzle OJ even when they're not hungry/thirsty. Ultimately we need to be aware of and respond to our cravings to natural foods. I do agree with you that it's not a one-size-fits-all thing. There's infinitely more to each one of us that we can possibly communicate over this forum.

This is pretty much the case with me. After Int-fasting plus aikido, I took a hunk of time to sort out liver and insulin sensitivity. There was a point where I had to eat frozen OJ concentrate and then that stopped. It was like an inflection point. At that time, I found I could also drink 800mg caffeine with no stress response. I could sleep through the night without having to get up to pee.
I did end up in a period of difficulty waking up. I was hypoventilating and my lungs felt lousy. I concentrated on anti-serotonin strategies and they recently cleared. My lungs feel expansive and I want to get up and be out.
I am thinking about protective/stress metabolism is akin to incorporating one's shadow side. Like if a person has their "good" puppet(persona) construct and their "bad" puppet simmering beneath as one they are not proud of, then neither of these puppets is even a person. They need to disambiguate to become an authentic person. And if a person has a big smile on their face but simmering beneath is adaptive stress metabolism all the time, then probably neither is a whole person. I think there must be a way to incorporate both to be alive in a fully healthful state.

 

[tara]

My understanding of this is that cortisol causes fats to be converted to glucose for energy production, whereas adrenaline causes glycogen to be converted to glucose.

Hmm. I think you are right that adrenaline has a role in getting the glycogen out into blood glucose again. Cortisol can sustain blood glucose by stimulating glyconeogenesis (conversion of protein to glucose), and reducing the rate of glucose oxidation and increasing the rate of fatty acid oxidation (not conversion to glucose, but I could be wrong there),

I think eating a large portion of carbohydrate at night, before sleep, may disrupt this cycle, and lead to poor sleep.

I think this may be what happens to me. If I don't eat enough earlier in the day, and go to bed hungry, I'm likely to not get to sleep, or to wake up too early. Alternatively, if I try to catch up and eat more in the evening I'll sleep, but I think it messes with the cycle, and I wake up not feeling so well. Best for me to eat more earlier in the day and less later in the evening. N=1.

 

[DuggaDugga]

How long did it take to repair your liver? Did you do anything specific to improve it or was it just diet/lifestyle changes?

I would say it took me the better part of a month to be able to start going substantial lengths of time (4-6 hours) without having to eat some sort of sugar. The great thing was that I didn't gain any weight doing this either- in fact I got super lean and vascular. I just followed my appetite and it was all good.

Hard to say how long exactly it took as there were so many things in-flight, so many things I was changing in my life for the better; I mean from mindfulness and controlled breathing to mostly quitting alcohol to removing PUFA- you name it. It's a gradual thing.

This is pretty much the case with me. After Int-fasting plus aikido, I took a hunk of time to sort out liver and insulin sensitivity. There was a point where I had to eat frozen OJ concentrate and then that stopped. It was like an inflection point. At that time, I found I could also drink 800mg caffeine with no stress response. I could sleep through the night without having to get up to pee.
I did end up in a period of difficulty waking up. I was hypoventilating and my lungs felt lousy. I concentrated on anti-serotonin strategies and they recently cleared. My lungs feel expansive and I want to get up and be out.
I am thinking about protective/stress metabolism is akin to incorporating one's shadow side. Like if a person has their "good" puppet(persona) construct and their "bad" puppet simmering beneath as one they are not proud of, then neither of these puppets is even a person. They need to disambiguate to become an authentic person. And if a person has a big smile on their face but simmering beneath is adaptive stress metabolism all the time, then probably neither is a whole person. I think there must be a way to incorporate both to be alive in a fully healthful state.

These are exactly the types of things I notice as well. Or I'll be able to go the day only needing to use the restroom like twice, versus the adrenaline-fueled constant gotta-go. The night time wake is something I'm still the sensitive to. Reading before bed and a spoonful of honey have been the two things that most reliably prevent it for me.

 

[yerrag]

@yerrag, many of your statements are way off. I don't have the time to break down all your errors. You definitely need to take a fresh look at cortisol cycles and gluconeogenesis.

I hope you can find some time @Colin Nordstrom. I've been eagerly waiting for a more complete response from you. I'm okay with the first part where you say I'm in error, and then you trail off.

 

[ceileachair]

Try chamomile tea. i sleep really well after it. It's actually got some pretty strong stuff in it.

 

[DHT]

i had the same problem and this waking up every night same time is dangerous sign that sth. in your body isnt in right circumstances. Be warned i would immedetially seek out whats the issue behind this. In my case i was burning too much and too fast pufas. And my liver got fu.ck.ed up as a consequence right kidney got fu.ck.ed up. My advice is to support your liver by detoxing the pufa with gluthation boosters. You can do it directly by lipposamal gluthation or by just eating more protein rich in sulfur compounds like eggs. also i would increase my vitamin e intake. Do not overdo with coffe because its a very powerfull fatburner in my case and burns pufas very fast. In my case orange juices helped me as well maybe due the vitamin c. I also read that in special times various organs doing there work. Comes from chinese, but i dont know if that is quackery or true

 

[yerrag]

Hmm. I think you are right that adrenaline has a role in getting the glycogen out into blood glucose again. Cortisol can sustain blood glucose by stimulating glyconeogenesis (conversion of protein to glucose), and reducing the rate of glucose oxidation and increasing the rate of fatty acid oxidation (not conversion to glucose, but I could be wrong there),

Yes, it would be interesting to find out if cortisol would also convert fatty acids to glucose, as well as metabolize fats through fatty oxidation. I have a feeling the answer is going to be complicated, and would depend on factors such as the chain length of the fatty acid, and the degree of unsaturation. @Travis could you help us out here?

 

[DuggaDugga]

Yes, it would be interesting to find out if cortisol would also convert fatty acids to glucose, as well as metabolize fats through fatty oxidation. I have a feeling the answer is going to be complicated, and would depend on factors such as the chain length of the fatty acid, and the degree of unsaturation. @Travis could you help us out here?

It varies depending on the type of cell. A few pages back I posted studies on cortisol causing general insulin resistance. Without even digging for references, we can take a basic understating of energy substrate utilization and the stressed state to understand why the body is acting "intelligently" in response to cortisol. Cortisol is a stress hormone. When in a survival situation (whether it's real of perceived) our bodies flood our system with energy substrates (fatty acids and glucose) to make it readily and rapidly available for the various cells of the body to survive. It's inefficient, but the body would rather operate inefficiently for short periods than to not survive.

Mechanisms of Glucocorticoid-Induced Insulin Resistance: Focus on Adipose Tissue Function and Lipid Metabolism

Insulin resistance, the common thread between obesity, the metabolic syndrome, and type 2 diabetes mellitus, is defined as the impaired ability of insulin to control nutrient partitioning in target organs. In adipose tissue, insulin fails to restrain lipolysis and increase glucose uptake; in liver, to inhibit hepatic gluconeogenesis and glycogenolysis; and in muscle, to induce glucose uptake. A critical function of GCs is to liberate energy substrates (ie, glucose, amino acids, and fatty acids [FA]), and thus ensure their availability for mitochondrial oxidation in fight-or-flight conditions. Thus, GCs enhance muscle protein breakdown, adipose tissue lipolysis, and hepatic gluconeogenesis, and reduce glucose utilization, effects which elevate circulating glucose concentrations (summarized in Fig. 1). Chronic GC overexposure alters body composition, which includes expansion of trunk adipose tissue depots, and impairs metabolism and insulin action, resulting in hyperglycemia and dyslipidemia.

Although GCs result in whole-body insulin resistance, this does not necessarily mean that they impair insulin action in each tissue. Recent work has shown that both endogenous and synthetic GCs may in fact enhance insulin signaling and action in human adipose tissue.25,27–29 For example, short-term (24 hours) pretreatment with GCs enhanced insulin-stimulated tyrosine phosphorylation of insulin receptor (IR) substrate protein 1 (IRS1) and protein kinase B/akt phosphorylation in human adipocytes derived from a subcutaneous adipose tissue biopsy.27 These effects, which were dose dependent and time dependent, occurred in the context of increased expression of IR, IRS2, and the p85 regulatory subunit of phopshoinositide-3-kinase.27,28 Subsequent work showed that both short-term (24 hours) and long-term (7 days) exposure of immortalized differentiated human adipocytes (Chub-S7 cells) to dexamethasone,29 enhanced insulin signaling, and seemed to prevent the insulin resistance caused by chronic high-dose insulin treatment.29 This finding is in agreement with a recent in vivo study performed in humans, whereby overnight administration of hydrocortisone resulted in systemic insulin resistance, but enhanced insulin action in subcutaneous adipose tissue.30

The ability of GCs to increase insulin sensitivity of adipose tissue contrasts with their effects on muscle where GCs decrease insulin-mediated glucose uptake. As shown in primary cell culture and cell lines, this may occur via stimulation of serine kinases, resulting in phosphorylation and inactivation of IR and IRS molecules.27,79 Accumulation of intramyocellular lipids (droplets of triglyceride in skeletal muscle fibers) is similarly associated with insulin resistance.80–84 Thus, intramyocellular lipid accumulation is thought to represent an early defect in the development of type 2 diabetes mellitus.85 Excessive accumulation of intramyocellular lipid could represent another mechanism by which GCs affect metabolism, but as yet it remains unclear as to whether this occurs during GC exposure in humans. However, a recent study using cell lines and rodent models demonstrated that GCs dysregulate lipid metabolism in skeletal muscle by enhancing β-oxidation and lipolysis.86 Furthermore, inhibition of 11β-HSD1, which is expressed in muscle,79 decreased lipogenic and lipolytic gene expression. Thus, GCs regulate both carbohydrate and lipid metabolism in skeletal muscle, which could play an important role in regulating muscle and whole-body insulin sensitivity.

Now, when we're stressed we've hyperglycemic and generally insulin resistant-- so where is this glucose intended to go? To the critical, glucose-dependent cells of the brain and to red blood cells, of particular relevance.

Brain glucose metabolism is controlled by amplification and desensitization of the neuronal insulin receptor. - PubMed - NCBI

Glucose metabolism is essential for brain function and structure. Glucose contributes to the formation of neurotransmitters and is normally the only source for energy formation. There is increasing evidence that brain glucose metabolism is under control of the neuronal insulin/insulin receptor signal transduction. The present data clearly show that intracerebroventricularly administered insulin exerts anabolic effects on cerebral glucose/energy metabolism (amplification of the neuronal insulin receptor complex) whereas cortisol (corticosterone) acts antagonistically (desensitization of the neuronal insulin receptor complex). It is also shown that short-term cortisol (corticosterone) enhanced energy turnover in temporoparietal cortex and hippocampus. In contrast, long-term cortisol (corticosterone) reduced energy turnover in both brain structures studied. This metabolic pattern is reminiscent of that found in very old age. Therefore, it is assumed that long-term cortisol accelerates the aging process in the brain and thus the risk for age-related disorders such as dementia.

Stress hyperglycemia: an essential survival response!

Glucose is largely utilized by tissues that are non-insulin dependent, and these include the central and peripheral nervous system, bone marrow, white and red blood cells and the reticuloendothelial system [20]. It has been estimated that, at rest, non-insulin mediated glucose uptake accounts for 75 to 85% of the total rate of whole glucose disposal. Glucose is the primary source of metabolic energy for the brain. Cellular glucose uptake is mediated by plasma membrane glucose transporters (GLUTs), which facilitate the movement of glucose down a concentration gradient across the non-polar lipid cell membrane

The pro-cortisol folk here have yet to explain with physiological reasoning why it's beneficial (outside of highly demanding, warranted isolated stress responses) to flood your system with energy substrate, to be generally insulin resistance, to shred skeletal muscle for gluconeogensis, to synthesize metabolically active abdominal adipose tissue, to lower digestion, to lower libido, to lower immunity (each of these anyone can research themselves), etc, etc, etc. The only responses I've seen so far have been personal anecdotes (which I don't mean to invalidate, but simply don't find them constructive) and responses like "the human body is just too complex".

 

[yerrag]

It varies depending on the type of cell. A few pages back I posted studies on cortisol causing general insulin resistance. Without even digging for references, we can take a basic understating of energy substrate utilization and the stressed state to understand why the body is acting "intelligently" in response to cortisol. Cortisol is a stress hormone. When in a survival situation (whether it's real of perceived) our bodies flood our system with energy substrates (fatty acids and glucose) to make it readily and rapidly available for the various cells of the body to survive. It's inefficient, but the body would rather operate inefficiently for short periods than to not survive.

Mechanisms of Glucocorticoid-Induced Insulin Resistance: Focus on Adipose Tissue Function and Lipid Metabolism




Now, when we're stressed we've hyperglycemic and generally insulin resistant-- so where is this glucose intended to go? To the critical, glucose-dependent cells of the brain and to red blood cells, of particular relevance.

Brain glucose metabolism is controlled by amplification and desensitization of the neuronal insulin receptor. - PubMed - NCBI


Stress hyperglycemia: an essential survival response!


The pro-cortisol folk here have yet to explain with physiological reasoning why it's beneficial (outside of highly demanding, warranted isolated stress responses) to flood your system with energy substrate, to be generally insulin resistance, to shred skeletal muscle for gluconeogensis, to synthesize metabolically active abdominal adipose tissue, to lower digestion, to lower libido, to lower immunity (each of these anyone can research themselves), etc, etc, etc. The only responses I've seen so far have been personal anecdotes (which I don't mean to invalidate, but simply don't find them constructive) and responses like "the human body is just too complex".

I agree that cortisol isn't a hormone that warrants a beneficial label but it seems to me though that it is still a hormone that has a significant influence especially during the late stages of normal sleeping hours. It is serving a needed purpose. Its strong influence during that stage of sleep is not to be considered as harmful, but it is how the other hormones such as progesterone, estrogen, and serotonin, and melatonin work together in making sleep restful while allowing the body to replenish its glycogen stores and to repair itself. And this has to take account that the body while at sleep is at a state of inhibition, with lowered metabolism, yet still isn't in a state of torpor, allowing it to use glucose and/or fat for energy. I feel that cortisol is very much needed during sleep because it serves to use protein and fats to augment the supply of glucose going into sleep. The glucose from food, and from gluconeogenesis from protein (and fats?) thru the action of cortisol - all added up, is the glucose used up efficiently by oxidative metabolism - to carry out regenerative processes, enzymatic activity, bolstering of immunity, detoxification, and replenishing of glycogen stores, and more - is what makes for a healthy and restful sleep. There is also the energy from fatty oxidation, thru cortisol, as energy is energy.