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Sleep Hygiene Isn’t Enough — Here’s Why You Still Can’t Sleep More Than 5–6 Hours
Sleep OS Hormones: https://thelongevityvault.com/sleep-os/hormones/
The Longevity Vault: https://thelongevityvault.com/
When we think about circadian rhythms and sleep, melatonin typically dominates the conversation as the hormone that signals darkness and initiates sleep onset.
But what’s not widely understood is that testosterone, estrogen, and progesterone also interact with the brain’s circadian control centers.
These hormones don’t just follow the clock’s rhythm—
they also help shape it.
Specifically, androgen (testosterone) and estrogen influence the suprachiasmatic nucleus (SCN), the body’s central clock, where they can modulate the molecular clock genes (Per2, Clock, and related regulators) that set the pace of biological activity across each 24-hour cycle.
Through these molecular pathways, testosterone, estrogen, and progesterone affect multiple aspects of sleep quality. They,
* stabilize temperature regulation,
* coordinate nighttime metabolism, and
* modulate the stress rhythms that determine whether sleep remains continuous or fragmented.
When these hormonal rhythms become less well-supported or dysregulated, whether from age-related susceptibility or chronic stress, the body’s internal timing becomes less precise, even if sleep hygiene remains robust.
Why?
Because sleep-hygiene affects only a subset of the factors that influence sleep.
It doesn’t support all the inputs that help us fall asleep and stay asleep.
Hormone function is one such input.
In the sections that follow, we’ll look at how testosterone, estrogen, and progesterone contribute to sleep through three interconnected systems—the body’s central clock, the stress rhythm, and the metabolic cycle—and how changes in hormonal regulation can affect the architecture of sleep.
1. Testosterone & Estrogen’s Modulation of the Body’s Central Clock (Suprachiasmatic Nucleus—”SCN”)
At the center of the brain’s timing system is the suprachiasmatic nucleus (SCN), the master clock that keeps every cell aligned to the 24-hour day.
Light is its dominant cue.
But hormones add another layer of circadian regulation:
* Some act as rhythm drivers, following their own daily cycles that affect gene expression in target tissues.
* Others function as zeitgebers—internal time cues that can shift or realign the phase of local clocks across the body.
* Still others behave as tuners, providing background signals that affect how strongly different tissues respond to external stimuli such as light, food, or temperature.
Through these roles, hormones help translate the central clock’s (SCN) master rhythm into synchronized activity across the body’s systems.
Among these, testosterone, estrogen, and progesterone act as both circadian messengers and stabilizers by sending timing cues from the SCN to peripheral organs to help coordinate their daily cycles of metabolism & tissue repair while fine-tuning the clock itself so its rhythm remains strong and adaptable under stress, shifting light, or in aging.
(This is partly why many individuals get morning sunlight yet still struggle with sleep—the central clock receives the light signal, but its stability also depends on a constellation of internal processes that may not be adequately supported.)
Testosterone
Testosterone influences how the SCN responds to light.
Research shows it can adjust both the phase, the timing of the clock, and its overall rhythmic strength. These effects are mediated through androgen receptors in SCN neurons, which fine-tune how sensitive the brain’s master clock is to morning light cues.
Through these processes, testosterone affects how easily the clock resets each morning and how consistently it keeps time from day to day.
When testosterone regulation becomes impaired, whether from sustained stress, metabolic strain, or the greater hormonal susceptibility that can develop with age, the strength of this circadian signal weakens. As a result, the body’s daily timing can drift, often showing up as earlier waking or lighter sleep.
Estrogen & Progesterone
Estrogen supports the SCN by improving coordination among its neurons.
This process, known as neural coupling, keeps individual clock cells communicating so they maintain a shared rhythm. Additionally, estrogen influences clock-gene expression—the molecular activity that establishes daily timing in each cell.
When these synchronizing effects weaken—whether through hormonal fluctuation or cumulative stress—the brain becomes more sensitive to disruption from light exposure or irregular schedules, and can make sleep timing less predictable.
Progesterone, meanwhile, supports the transition between wakefulness and rest through its neurosteroid metabolites that enhance calming GABA_A activity, helping maintain stability across the sleep–wake cycle.
Together, these hormonal interactions reinforce the body’s circadian precision.
In younger adults, strong daily fluctuations in testosterone and ovarian hormones amplify the rhythm established by light.
With susceptibility from stress or later life, that circadian signal can weaken, making it harder for the body to stay in sync.
2. Hormonal Regulation of the Stress Rhythm (HPA Axis)
If the SCN keeps time, the hypothalamic–pituitary–adrenal (HPA) axis regulates the body’s stress rhythm, the daily pattern of cortisol release that affects how energized we feel through the day and how easily we unwind at night.
Specifically, the HPA axis functions as a feedback loop linking the brain and adrenal glands.
In this loop, the hypothalamus releases corticotropin-releasing hormone (CRH), which signals the pituitary gland to secrete adrenocorticotropic hormone (ACTH). ACTH then cues the adrenal glands to produce cortisol, the hormone that mobilizes energy for activity and gradually tapers toward evening to allow rest.
Testosterone, estrogen and progesterone all influence how tightly this stress rhythm stays controlled.
Testosterone
Testosterone tends to dampen HPA reactivity and strengthen feedback control.
It helps regulate CRH and ACTH output and reinforces the feedback loop that signals the brain when cortisol levels are adequate. This feedback integrity allows cortisol to rise clearly in the morning to support alertness and taper by evening so the body can relax.
When testosterone function weakens— the braking effect can loosen, and cortisol can remain elevated late into the night and affect sleep quality and continuity.
Estrogen & Progesterone
Estrogen may have the opposite influence.
It can heighten HPA responsiveness by increasing the stress-signaling messengers CRH and ACTH output and by reducing feedback sensitivity in certain contexts and phases. Elevated or fluctuating estrogen levels can therefore extend the cortisol curve and delay full relaxation at night.
Progesterone provides the moderating counterweight. Through its GABA-enhancing metabolites, it contributes to neuronal calm and supports faster recovery after stress exposure. When progesterone and estrogen are balanced, the HPA axis can respond robustly but still settle before sleep.
As hormonal regulation becomes less robust, whether from stress overload or the cumulative susceptibility that comes with later life—these relationships shift. Testosterone’s regulatory grip loosen. Estrogen and progesterone patterns become irregular or diminish.
The result is a less well-regulated cortisol rhythm, spikes that appear too late or persist too long.
In daily life, this can feel like the 3 a.m. alertness that arrives without cause.
Maintaining strong hormonal function and cross-system regulation helps preserve a healthy stress rhythm across life stages. When cortisol rises and falls in proper sequence with the light–dark cycle, the body maintains the clear physiological boundaries between day activation and nighttime restoration that sleep depends on.
3. Metabolic Coordination and Sleep Continuity
The body’s ability to stay asleep depends not only on timing and stress control but also on how efficiently it manages energy through the night.
While the circadian and stress systems influence when rest occurs, the metabolic system affects whether that sleep remains stable.
Testosterone
Testosterone plays a key role in this coordination.
It helps regulate how the body uses and conserves energy during sleep by maintaining muscle mass, glucose disposal, and mitochondrial efficiency. More lean tissue means better glycogen storage for the overnight fast, steadier glucose supply to the brain, and fewer metabolic dips that can trigger wakefulness. Testosterone also supports mitochondrial activity, which keeps cellular energy production steady when external fuel is unavailable.
When testosterone function becomes affected, these mechanisms can weaken. Blood glucose can drop too low or rebound too sharply, leading to sympathetic activation and early or fragmented waking.
Estrogen & Progesterone
Estrogen contributes to the same metabolic stability from a different angle.
It improves insulin sensitivity and helps tissues absorb glucose more effectively to keep nighttime energy use balanced. It also assists with thermal regulation that smooths the body’s temperature curve across the night. When levels fall, through (peri)-menopause or stress, both temperature control and metabolic steadiness can fluctuate, which can interrupt sleep.
Progesterone supports these rhythms by modulating body temperature and influencing mitochondrial performance via neurosteroid pathways. Its natural rise after ovulation slightly increases core temperature and is associated with more consolidated sleep. When progesterone drops, thermoregulation becomes less consistent and can contribute to alternating sensations of warmth and chill that fragment sleep.
Together, these hormones contribute to a 24-hour energy rhythm: cortisol mobilizes fuel in the morning, insulin manages nutrient storage through the day, and sex hormones maintain metabolic calm through the night.
When that hormonal rhythm becomes less robust, the body interprets metabolic fluctuations as an alert that causes awakenings that feel spontaneous.
Testosterone & Estrogen Function & Sleep Architecture
Melatonin helps the body recognize night, but it isn’t the sole timekeeper.
For decades, research has shown that sex hormones, testosterone, estrogen, and progesterone, also interact with the brain’s circadian system.
Their influence is less widely recognized, yet these hormones fine-tune the same network that melatonin signals.
Together, they influence multiple interconnected systems: within the SCN to stabilize timing, through the HPA axis to align cortisol’s daily rhythm, and across metabolic pathways to maintain glucose and temperature balance, all foundations for uninterrupted sleep.
As hormonal function becomes less well-regulated, whether through the greater susceptibility that often develops with age or through stress, these patterns begin to flatten.
* Testosterone’s morning peaks may lose amplitude and timing precision.
* Estrogen and progesterone cycles can become irregular or phase-shifted.
During sustained stress, the stress-response network can dominate endocrine signaling, and this reduces the regulatory contributions that sex hormones have on sleep stability.
The result is a body that still responds to light cues but has weaker internal coordination to make sleep effortless.
Recognizing this broader hormonal role reframes how we think about sleep itself.
Not as a nightly event, but as the downstream expression of well-regulated hormonal function.
When hormonal regulation is supported, whether addressing the functional decline that becomes more common with age or under chronic stress, the body remains responsive to circadian cues, resilient under pressure, and capable of the kind of restorative sleep that underpins long-term vitality.
Moving Beyond Sleep Hygiene
For most of my adult life, my own sleep didn’t reflect that balance.
I experienced various forms of sleep issues that so many individuals face.
Sometimes it was falling asleep. Other times it was waking up at 2 or 3am and not being able to get back to deep rest.
And, like many, I tried all the standard approaches for years without consistent results.
Once I stopped focusing only on sleep onset and started looking at what was disrupting continuity, my sleep became much more stable.
The breakthrough came from shifting perspective—instead of asking “How do I fall asleep better?” I started asking “What’s preventing my brain from staying in restorative stages?”
The answer wasn’t another supplement or bedtime routine. It was recognizing that sleep depends on multiple biological systems working together, and each one needs to be supported.
Hormones were one of those systems.
Estrogen, testosterone, and progesterone each help stabilize the body’s circadian clock, regulate the daily cortisol rhythm, and maintain metabolic steadiness through the night.
Without addressing how well these hormones were functioning and maintaining their regulatory balance, that piece of my sleep remained unstable, no matter how good my sleep hygiene was.
This isn’t about hormones being the only thing that matters. But they are one that’s often under-supported. When hormonal regulation is less resilient, whether through changes that become more common in aging or through chronic stress, sleep becomes fragile even when habits are strong.
Once I began supporting hormonal function alongside the other biological systems that maintain sleep continuity, my sleep improved in ways that light and caffeine timing never could.
It’s the same approach I’ve used with clients in later life stages or under sustained stress who had already optimized every habit yet still woke at 3 a.m.
This systems perspective became the foundation for Sleep OS: Hormones, a structured, self-guided program built to support the hormonal function and regulation that keep the body’s timing network stable through the night.
Warmly,—Kat
P.S. If you’ve been following my work on sleep and hormones, you’ll know how much depth there is beneath the surface.
If you’re ready to go deeper and take a systems-based approach to improving your sleep, Sleep OS Hormones is now available as a 60-day self-guided program with dedicated systems for estrogen, progesterone, and testosterone, or bundled together for a more complete approach.
Learn more about Sleep OS Hormones →
or See which version of Sleep OS Hormones is right for you →
(To mark the first digital release of my Sleep OS Hormone Systems, Charter Access is open until October 17. This early-access window includes introductory pricing, exclusive Charter Access bonuses, and a bespoke Vault Strategy Consultation—so you can get my private feedback insight on your specific sleep challenges and accelerate your sleep recovery process.)
References:
* Begemann, K., et al. (2025). Endocrine regulation of circadian rhythms. Nature Reviews Endocrinology.
* Georgios K Paschos, Ronan Lordan, Garret A Fitzgerald, Intersection of sex and circadian biology, Current Opinion in Physiology, Volume 45, 2025, 100834
* Model Z, Butler MP, LeSauter J, Silver R. Suprachiasmatic nucleus as the site of androgen action on circadian rhythms. Horm Behav. 2015 Jul;73:1-7.
* Alana M C Brown, Nicole J Gervais, Role of Ovarian Hormones in the Modulation of Sleep in Females Across the Adult Lifespan, Endocrinology, Volume 161, Issue 9, September 2020
* Gotlieb N, Moeller J, Kriegsfeld LJ. Circadian Control of Neuroendocrine Function: Implications for Health and Disease. Curr Opin Physiol. 2018 Oct;5:133-140.
* Mong JA, Baker FC, Mahoney MM, Paul KN, Schwartz MD, Semba K, Silver R. Sleep, rhythms, and the endocrine brain: influence of sex and gonadal hormones. J Neurosci. 2011 Nov 9;31(45):16107-16.
This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit thelongevityvault.substack.com/subscribe
View all episodes
By Kat Fu, M.S., M.S.Sleep OS Hormones: https://thelongevityvault.com/sleep-os/hormones/
The Longevity Vault: https://thelongevityvault.com/
When we think about circadian rhythms and sleep, melatonin typically dominates the conversation as the hormone that signals darkness and initiates sleep onset.
But what’s not widely understood is that testosterone, estrogen, and progesterone also interact with the brain’s circadian control centers.
These hormones don’t just follow the clock’s rhythm—
they also help shape it.
Specifically, androgen (testosterone) and estrogen influence the suprachiasmatic nucleus (SCN), the body’s central clock, where they can modulate the molecular clock genes (Per2, Clock, and related regulators) that set the pace of biological activity across each 24-hour cycle.
Through these molecular pathways, testosterone, estrogen, and progesterone affect multiple aspects of sleep quality. They,
* stabilize temperature regulation,
* coordinate nighttime metabolism, and
* modulate the stress rhythms that determine whether sleep remains continuous or fragmented.
When these hormonal rhythms become less well-supported or dysregulated, whether from age-related susceptibility or chronic stress, the body’s internal timing becomes less precise, even if sleep hygiene remains robust.
Why?
Because sleep-hygiene affects only a subset of the factors that influence sleep.
It doesn’t support all the inputs that help us fall asleep and stay asleep.
Hormone function is one such input.
In the sections that follow, we’ll look at how testosterone, estrogen, and progesterone contribute to sleep through three interconnected systems—the body’s central clock, the stress rhythm, and the metabolic cycle—and how changes in hormonal regulation can affect the architecture of sleep.
1. Testosterone & Estrogen’s Modulation of the Body’s Central Clock (Suprachiasmatic Nucleus—”SCN”)
At the center of the brain’s timing system is the suprachiasmatic nucleus (SCN), the master clock that keeps every cell aligned to the 24-hour day.
Light is its dominant cue.
But hormones add another layer of circadian regulation:
* Some act as rhythm drivers, following their own daily cycles that affect gene expression in target tissues.
* Others function as zeitgebers—internal time cues that can shift or realign the phase of local clocks across the body.
* Still others behave as tuners, providing background signals that affect how strongly different tissues respond to external stimuli such as light, food, or temperature.
Through these roles, hormones help translate the central clock’s (SCN) master rhythm into synchronized activity across the body’s systems.
Among these, testosterone, estrogen, and progesterone act as both circadian messengers and stabilizers by sending timing cues from the SCN to peripheral organs to help coordinate their daily cycles of metabolism & tissue repair while fine-tuning the clock itself so its rhythm remains strong and adaptable under stress, shifting light, or in aging.
(This is partly why many individuals get morning sunlight yet still struggle with sleep—the central clock receives the light signal, but its stability also depends on a constellation of internal processes that may not be adequately supported.)
Testosterone
Testosterone influences how the SCN responds to light.
Research shows it can adjust both the phase, the timing of the clock, and its overall rhythmic strength. These effects are mediated through androgen receptors in SCN neurons, which fine-tune how sensitive the brain’s master clock is to morning light cues.
Through these processes, testosterone affects how easily the clock resets each morning and how consistently it keeps time from day to day.
When testosterone regulation becomes impaired, whether from sustained stress, metabolic strain, or the greater hormonal susceptibility that can develop with age, the strength of this circadian signal weakens. As a result, the body’s daily timing can drift, often showing up as earlier waking or lighter sleep.
Estrogen & Progesterone
Estrogen supports the SCN by improving coordination among its neurons.
This process, known as neural coupling, keeps individual clock cells communicating so they maintain a shared rhythm. Additionally, estrogen influences clock-gene expression—the molecular activity that establishes daily timing in each cell.
When these synchronizing effects weaken—whether through hormonal fluctuation or cumulative stress—the brain becomes more sensitive to disruption from light exposure or irregular schedules, and can make sleep timing less predictable.
Progesterone, meanwhile, supports the transition between wakefulness and rest through its neurosteroid metabolites that enhance calming GABA_A activity, helping maintain stability across the sleep–wake cycle.
Together, these hormonal interactions reinforce the body’s circadian precision.
In younger adults, strong daily fluctuations in testosterone and ovarian hormones amplify the rhythm established by light.
With susceptibility from stress or later life, that circadian signal can weaken, making it harder for the body to stay in sync.
2. Hormonal Regulation of the Stress Rhythm (HPA Axis)
If the SCN keeps time, the hypothalamic–pituitary–adrenal (HPA) axis regulates the body’s stress rhythm, the daily pattern of cortisol release that affects how energized we feel through the day and how easily we unwind at night.
Specifically, the HPA axis functions as a feedback loop linking the brain and adrenal glands.
In this loop, the hypothalamus releases corticotropin-releasing hormone (CRH), which signals the pituitary gland to secrete adrenocorticotropic hormone (ACTH). ACTH then cues the adrenal glands to produce cortisol, the hormone that mobilizes energy for activity and gradually tapers toward evening to allow rest.
Testosterone, estrogen and progesterone all influence how tightly this stress rhythm stays controlled.
Testosterone
Testosterone tends to dampen HPA reactivity and strengthen feedback control.
It helps regulate CRH and ACTH output and reinforces the feedback loop that signals the brain when cortisol levels are adequate. This feedback integrity allows cortisol to rise clearly in the morning to support alertness and taper by evening so the body can relax.
When testosterone function weakens— the braking effect can loosen, and cortisol can remain elevated late into the night and affect sleep quality and continuity.
Estrogen & Progesterone
Estrogen may have the opposite influence.
It can heighten HPA responsiveness by increasing the stress-signaling messengers CRH and ACTH output and by reducing feedback sensitivity in certain contexts and phases. Elevated or fluctuating estrogen levels can therefore extend the cortisol curve and delay full relaxation at night.
Progesterone provides the moderating counterweight. Through its GABA-enhancing metabolites, it contributes to neuronal calm and supports faster recovery after stress exposure. When progesterone and estrogen are balanced, the HPA axis can respond robustly but still settle before sleep.
As hormonal regulation becomes less robust, whether from stress overload or the cumulative susceptibility that comes with later life—these relationships shift. Testosterone’s regulatory grip loosen. Estrogen and progesterone patterns become irregular or diminish.
The result is a less well-regulated cortisol rhythm, spikes that appear too late or persist too long.
In daily life, this can feel like the 3 a.m. alertness that arrives without cause.
Maintaining strong hormonal function and cross-system regulation helps preserve a healthy stress rhythm across life stages. When cortisol rises and falls in proper sequence with the light–dark cycle, the body maintains the clear physiological boundaries between day activation and nighttime restoration that sleep depends on.
3. Metabolic Coordination and Sleep Continuity
The body’s ability to stay asleep depends not only on timing and stress control but also on how efficiently it manages energy through the night.
While the circadian and stress systems influence when rest occurs, the metabolic system affects whether that sleep remains stable.
Testosterone
Testosterone plays a key role in this coordination.
It helps regulate how the body uses and conserves energy during sleep by maintaining muscle mass, glucose disposal, and mitochondrial efficiency. More lean tissue means better glycogen storage for the overnight fast, steadier glucose supply to the brain, and fewer metabolic dips that can trigger wakefulness. Testosterone also supports mitochondrial activity, which keeps cellular energy production steady when external fuel is unavailable.
When testosterone function becomes affected, these mechanisms can weaken. Blood glucose can drop too low or rebound too sharply, leading to sympathetic activation and early or fragmented waking.
Estrogen & Progesterone
Estrogen contributes to the same metabolic stability from a different angle.
It improves insulin sensitivity and helps tissues absorb glucose more effectively to keep nighttime energy use balanced. It also assists with thermal regulation that smooths the body’s temperature curve across the night. When levels fall, through (peri)-menopause or stress, both temperature control and metabolic steadiness can fluctuate, which can interrupt sleep.
Progesterone supports these rhythms by modulating body temperature and influencing mitochondrial performance via neurosteroid pathways. Its natural rise after ovulation slightly increases core temperature and is associated with more consolidated sleep. When progesterone drops, thermoregulation becomes less consistent and can contribute to alternating sensations of warmth and chill that fragment sleep.
Together, these hormones contribute to a 24-hour energy rhythm: cortisol mobilizes fuel in the morning, insulin manages nutrient storage through the day, and sex hormones maintain metabolic calm through the night.
When that hormonal rhythm becomes less robust, the body interprets metabolic fluctuations as an alert that causes awakenings that feel spontaneous.
Testosterone & Estrogen Function & Sleep Architecture
Melatonin helps the body recognize night, but it isn’t the sole timekeeper.
For decades, research has shown that sex hormones, testosterone, estrogen, and progesterone, also interact with the brain’s circadian system.
Their influence is less widely recognized, yet these hormones fine-tune the same network that melatonin signals.
Together, they influence multiple interconnected systems: within the SCN to stabilize timing, through the HPA axis to align cortisol’s daily rhythm, and across metabolic pathways to maintain glucose and temperature balance, all foundations for uninterrupted sleep.
As hormonal function becomes less well-regulated, whether through the greater susceptibility that often develops with age or through stress, these patterns begin to flatten.
* Testosterone’s morning peaks may lose amplitude and timing precision.
* Estrogen and progesterone cycles can become irregular or phase-shifted.
During sustained stress, the stress-response network can dominate endocrine signaling, and this reduces the regulatory contributions that sex hormones have on sleep stability.
The result is a body that still responds to light cues but has weaker internal coordination to make sleep effortless.
Recognizing this broader hormonal role reframes how we think about sleep itself.
Not as a nightly event, but as the downstream expression of well-regulated hormonal function.
When hormonal regulation is supported, whether addressing the functional decline that becomes more common with age or under chronic stress, the body remains responsive to circadian cues, resilient under pressure, and capable of the kind of restorative sleep that underpins long-term vitality.
Moving Beyond Sleep Hygiene
For most of my adult life, my own sleep didn’t reflect that balance.
I experienced various forms of sleep issues that so many individuals face.
Sometimes it was falling asleep. Other times it was waking up at 2 or 3am and not being able to get back to deep rest.
And, like many, I tried all the standard approaches for years without consistent results.
Once I stopped focusing only on sleep onset and started looking at what was disrupting continuity, my sleep became much more stable.
The breakthrough came from shifting perspective—instead of asking “How do I fall asleep better?” I started asking “What’s preventing my brain from staying in restorative stages?”
The answer wasn’t another supplement or bedtime routine. It was recognizing that sleep depends on multiple biological systems working together, and each one needs to be supported.
Hormones were one of those systems.
Estrogen, testosterone, and progesterone each help stabilize the body’s circadian clock, regulate the daily cortisol rhythm, and maintain metabolic steadiness through the night.
Without addressing how well these hormones were functioning and maintaining their regulatory balance, that piece of my sleep remained unstable, no matter how good my sleep hygiene was.
This isn’t about hormones being the only thing that matters. But they are one that’s often under-supported. When hormonal regulation is less resilient, whether through changes that become more common in aging or through chronic stress, sleep becomes fragile even when habits are strong.
Once I began supporting hormonal function alongside the other biological systems that maintain sleep continuity, my sleep improved in ways that light and caffeine timing never could.
It’s the same approach I’ve used with clients in later life stages or under sustained stress who had already optimized every habit yet still woke at 3 a.m.
This systems perspective became the foundation for Sleep OS: Hormones, a structured, self-guided program built to support the hormonal function and regulation that keep the body’s timing network stable through the night.
Warmly,—Kat
P.S. If you’ve been following my work on sleep and hormones, you’ll know how much depth there is beneath the surface.
If you’re ready to go deeper and take a systems-based approach to improving your sleep, Sleep OS Hormones is now available as a 60-day self-guided program with dedicated systems for estrogen, progesterone, and testosterone, or bundled together for a more complete approach.
Learn more about Sleep OS Hormones →
or See which version of Sleep OS Hormones is right for you →
(To mark the first digital release of my Sleep OS Hormone Systems, Charter Access is open until October 17. This early-access window includes introductory pricing, exclusive Charter Access bonuses, and a bespoke Vault Strategy Consultation—so you can get my private feedback insight on your specific sleep challenges and accelerate your sleep recovery process.)
References:
* Begemann, K., et al. (2025). Endocrine regulation of circadian rhythms. Nature Reviews Endocrinology.
* Georgios K Paschos, Ronan Lordan, Garret A Fitzgerald, Intersection of sex and circadian biology, Current Opinion in Physiology, Volume 45, 2025, 100834
* Model Z, Butler MP, LeSauter J, Silver R. Suprachiasmatic nucleus as the site of androgen action on circadian rhythms. Horm Behav. 2015 Jul;73:1-7.
* Alana M C Brown, Nicole J Gervais, Role of Ovarian Hormones in the Modulation of Sleep in Females Across the Adult Lifespan, Endocrinology, Volume 161, Issue 9, September 2020
* Gotlieb N, Moeller J, Kriegsfeld LJ. Circadian Control of Neuroendocrine Function: Implications for Health and Disease. Curr Opin Physiol. 2018 Oct;5:133-140.
* Mong JA, Baker FC, Mahoney MM, Paul KN, Schwartz MD, Semba K, Silver R. Sleep, rhythms, and the endocrine brain: influence of sex and gonadal hormones. J Neurosci. 2011 Nov 9;31(45):16107-16.
This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit thelongevityvault.substack.com/subscribe