This article has been medically reviewed by MD Niklas Marizy, Head of Medical at Adon Health.
Sleep is not a luxury; it's a physiological necessity. Especially for men between 25 and 60 who struggle with declining energy, decreased libido, or muscle loss, sleep can be a crucial factor in maintaining hormonal balance. Testosterone, the key hormone for vitality and male health, is primarily produced during sleep. This article explores the scientifically proven link between sleep and testosterone and explains how sleep deprivation disrupts the hormonal balance. We also discuss the potential impact of testosterone replacement therapy (TRT) on sleep quality.
What is testosterone and why is it so important?
Testosterone is the most important male sex hormone. Among other things, it regulates muscle growth, bone density, fat distribution, libido, mood, and cognitive function. It is primarily produced in the Leydig cells of the testes under the control of luteinizing hormone (LH) from the pituitary gland. From the age of 30, testosterone levels decline on average by about 1 to 2% per year ( Jones, 2012 ). A deficiency can manifest itself in symptoms such as chronic fatigue, depressed mood, loss of libido, and muscle loss ( Ferreira & Mendonça, 2022 ; Shores et al., 2005 ).
The circadian rhythm: Why testosterone levels are highest in the morning
Testosterone is released rhythmically. Concentrations are highest in the morning, especially between 7 and 10 a.m. ( Vesper et al., 2010 ). This increase is linked to the circadian rhythm: at night, particularly during REM sleep in the second half of the night, secretion reaches its peak ( Leproult et al., 2011 ).
A disrupted circadian rhythm due to shift work, jet lag, or irregular sleep patterns can severely disrupt the hormonal balance.
How sleep affects testosterone production
Even a single night of reduced or interrupted sleep can significantly lower testosterone levels the following day ( Luboshitzky et al., 2001 ). A study from the University of Chicago showed that just five hours of sleep per night over a week reduced testosterone levels in healthy men by 10 to 15% ( Leproult et al., 2011 ).
Studies in older men also confirm this connection: Less than six hours of sleep per night is associated with a significantly higher risk of testosterone deficiency ( Zhou et al., 2023 ).
REM sleep: The hormonally active phase
REM sleep is crucial for testosterone synthesis. During this phase, testosterone secretion increases sharply, especially with uninterrupted sleep ( Luboshitzky et al., 2001 ). Those who wake up frequently at night, for example due to stress or sleep apnea, lose valuable REM time and thus important testosterone production.
In addition, it was shown that men with a high proportion of REM sleep during the day were significantly more efficient and resistant to stress – an indirect effect of hormonal balance.
What happens when we lack sleep?
- Elevated cortisol levels: Lack of sleep leads to an increase in the stress hormone cortisol. This acts antagonistically to testosterone and directly inhibits its production via various hormonal axes ( Wittert, 2014 ). You can learn more about stress and testosterone in this blog article: Managing Stress – Staying Healthy and Productive as a Man
- Reduction of LH and GnRH: Sleep deprivation impairs the release of LH and GnRH, which are essential for testosterone production ( Anaissie et al., 2017 ).
- Increased risk of metabolic disorders: Chronic sleep deprivation promotes insulin resistance, weight gain and fat accumulation – all factors that further lower testosterone levels.
- Increase in psychological symptoms: Men with testosterone deficiency due to sleep deprivation often complain of lack of motivation, irritability, and depressive moods.
The vicious cycle: Testosterone deficiency worsens sleep
- Disrupted sleep architecture: Low testosterone levels lead to fewer deep sleep and REM phases. The result is non-restorative sleep and daily fatigue ( McBride et al., 2016 ).
- Increased arousal frequency: Men with hypogonadism wake up more frequently at night. This reduces total sleep time and disrupts hormonal regeneration ( McBride et al., 2016 ).
- Increase in sleep disorders: Low testosterone is associated with a higher prevalence of difficulty falling asleep and staying asleep. Targeted treatment of the hormone deficiency can provide relief ( Shlykova et al., 2020 ).
Sleep apnea: The hidden testosterone robber
- Reduction of REM sleep time: Sleep apnea interrupts REM sleep and leads to a measurable decrease in testosterone levels. Hormonal regeneration is severely impaired.
- Increased risk of testosterone deficiency: Men with untreated sleep apnea often have significantly lower testosterone levels than healthy sleepers ( Gambineri et al., 2003 ).
- Important screening measure: Screening for sleep apnea is recommended before starting TRT to minimize risks.
TRT and sleep: What does the research say?
- Improved REM sleep: Studies show that medically supervised TRT can improve the duration and quality of REM sleep. Hypogonadal men, in particular, benefit from this ( Barrett-Connor et al., 2008 ).
- Increased sleep efficiency: TRT can shorten the time it takes to fall asleep and increase sleep efficiency. Many patients report more restful and deeper sleep ( Barrett-Connor et al., 2008 ).
- Caution regarding overdose: If testosterone is taken in excessively high doses, e.g., for doping purposes, it can lead to sleep disturbances and central sleep apnea. Medically supervised testosterone replacement therapy (TRT) avoids such risks ( Liu et al., 2003 ).
Action recommendations: How to optimize your sleep, and thus your testosterone levels
- Maintain a consistent sleep schedule: Go to bed at the same time every day, even on weekends. A stable circadian rhythm promotes natural testosterone production ( Vesper et al., 2010 ).
- Avoid blue light: Reduce screen time at least one hour before bedtime. Blue light inhibits melatonin production, which helps you fall asleep faster ( Leproult et al., 2011 ).
- Create an optimal sleep environment: Ensure darkness, quiet, and a room temperature between 16 and 18 °C ( Luboshitzky et al., 1999 ).
- Avoid evening stimuli: No intense exercise or heavy meals before bed ( Leproult et al., 2011 ).
- Stress reduction: Mindfulness training can lower cortisol and improve sleep quality ( Wittert, 2014 ).
- Substance abstinence: Avoid alcohol, nicotine and caffeine ( McBride et al., 2016 ).
- Ensure adequate micronutrient intake: Zinc and magnesium support sleep and testosterone production ( Davis et al., 2015 ).
- Fresh air and daylight: Sunlight in the morning improves melatonin regulation ( Vesper et al., 2010 ).
🎧 Dr. Martin Schlott, chief physician and sleep expert, shares his sleep tips in our men's health podcast. Listen to the episode here.
Conclusion
Sleep is fundamental to male health and key to natural testosterone production. Regularly poor sleep can lead to hormonal imbalances with far-reaching consequences: loss of libido, muscle weakness, and mental exhaustion. At the same time, a testosterone deficiency can negatively impact sleep.
The good news: Even small changes in daily life – better sleep, less stress, targeted exercise – can have significant hormonal effects. Furthermore, individually tailored testosterone therapy under medical supervision can not only alleviate the symptoms of a deficiency but also improve sleep, provided all factors have been carefully investigated.
