The body’s internal clock related to light & hormones/neurotransmitters for restful sleep
I have deep empathy and compassion for those who experience sleep disturbances, as I, too, have faced the consequences. Sleep deprivation has negatively affected my health, wellness, and overall life satisfaction. Sleep is a fundamental need for all living beings.
For years, I struggled with sleep deprivation, particularly during night shifts in stressful work environments. It led to serious health problems like weight gain, abdominal obesity, prediabetes, and brain fog.
It took me a long time to recognize sleep’s vital role in the body and mind. This realization drove me to study how the brain controls sleep via daily rhythms. Inspired by my progress, I began writing about natural sleep regulation through healthy lifestyle choices.
I am inspired to write this story based on a follow on an important blog post I syndicated on multiple platforms yesterday. Readers found this story as an eye-opener, as I expected, and asked me to elaborate on the sleep aspect as apparently so many people suffer from sleep issues. Please find the link to this important post if you have missed it.
Brain Recharge: 3 Essential Rests You Need for Peak Cognitive Performance
Why Sleep, Mental Breaks, and Downtime Are the Secret Weapons Your Brain Needs to Thrive, Slow Aging, and Prevent…medium.com
In this concise story, I will summarize key points of sleep biology and biochemistry based on my research and experience to give some ideas on essential factors affecting our sleep from biological, physical, and chemical perspectives. As I covered the scientific aspects in detail before, I will not cite those studies to keep this post short, but you can find them in the stories I link below.
What is the SCN and Why Does it Matter?
The Suprachiasmatic Nucleus (SCN) is a small but powerful part of the brain located just above the optic nerves. It regulates our circadian rhythm, acting as a personal timekeeper that adjusts our internal clock based on external signals, especially light.
Morning light tells the SCN it’s time to wake up, while darkness signals the pineal gland to release melatonin for sleep. Ignoring these cues — like staying up late with screens — disrupts the SCN’s ability to regulate sleep.
Light exposure profoundly affects the SCN and, by extension, sleep patterns. Spending mornings indoors without sunlight can make waking up more difficult, while excessive bright light at night — especially from screens — confuses the brain into thinking it’s still daytime, making it harder to fall asleep.
When I worked night shifts, the lack of a natural light-dark cycle disrupted my sleep and health. It wasn’t until I learned about the SCN and made changes, like getting morning sunlight and limiting nighttime screens, that my sleep improved.
Recently, I summarized my research about the effects of light in a detailed story highlighting important scientific reviews and critical findings.
The Striking Adverse Effects of Night Light Exposure on Mental Health
Insights from a recent rigorous/large-size study indicate that increased exposure to light at night increases the risk…medium.com
Hormones and Neurotransmitters Impacting Sleep
Our hormones and neurotransmitters play a complex role in sleep. Adenosine builds up during the day, creating “sleep pressure” that signals the brain it’s time to rest. I disrupted this process by overusing caffeine, which blocks adenosine.
Melatonin, released by the pineal gland in response to darkness, signals sleep readiness. However, late-night screen use suppressed my melatonin production. Cortisol, which provides energy in the morning, became erratic due to my irregular sleep patterns, causing fatigue during the day and restlessness at night.
Neurotransmitters like GABA, acetylcholine, dopamine, norepinephrine, and histamine also influence sleep. GABA promotes deep sleep by calming brain activity, while acetylcholine is key for REM sleep and dreaming. Elevated levels of dopamine and norepinephrine can disrupt sleep, and histamine promotes wakefulness, explaining why antihistamines cause drowsiness.
Neuropeptides such as vasopressin and vasoactive intestinal peptide regulate the SCN’s timing and coordination. The retinohypothalamic tract (RHT) connects light-sensitive retinal cells to the SCN, where glutamate helps maintain circadian rhythms.
Pituitary adenylate cyclase-activating polypeptide (PACAP) from retinal ganglion cells enhances this process. The geniculohypothalamic tract (GHT) also provides indirect photic input to the SCN through neurotransmitters like neuropeptide Y, GABA, and enkephalin, further influencing circadian regulation.
Understanding how hormones and neurotransmitters work together has changed my approach to sleep. Respecting the body’s natural rhythms has been key.
I now step outside for natural light within an hour of waking, stick to a consistent sleep schedule, limit blue light exposure at night, and practice relaxation techniques before bed. These changes have helped me sleep better, feel more energetic, and think more clearly.
I wrote a detailed story about the neurobiology of the Suprachiasmatic Nucleus, including biochemical relationships and effects, based on my years of research.
Sleep Regulation: Neurobiology of the Suprachiasmatic Nucleus
I explain how the brain regulates circadian rhythms and whether a literal “clock” exists within it in simple terms…medium.com
Conclusions and Key Takeaways
The SCN, adenosine, melatonin, cortisol, and neurotransmitters that I mentioned are critical in regulating sleep. We can improve both sleep and overall health by honoring their natural cycles. If these strategies don’t work, consulting a sleep specialist is a good next step. Here are some practical tips to improve your sleep in a checklist format.
☐ Spend at least 30 minutes in natural sunlight each morning or use a light therapy box in low-sunlight regions.
☐ Go to bed and wake up at the same time every day, even on weekends.
☐ Dim lights and limit screen time in the evening to avoid blue light disruption.
☐ Avoid heavy meals, caffeine, nicotine, and alcohol near bedtime. Regular exercise and a balanced diet can support better sleep.
☐ Practice relaxation techniques like meditation, yoga,or diagraphmatic/deep breathing to wind down before bed.
☐ Observe sleep patterns using a smartwatch or tracker and consult a sleep specialist if issues arise.
Meditation Can Boost the Cortical Thickness in the Brain and Prevent It from Thinning
Although all cells, tissues, organs, and systems contribute to regulating sleep, the brain and nervous system play the most critical role. To effectively regulate sleep, the brain requires a balance of both stimulation and rest. I discussed these details further in the following two stories.
Related these two key processes I detailed the practical tips in the following stories.
Here’s How I Train My Brain Daily for Mental Clarity and Intellectual Productivity.
Here’s How to Make the Nervous System More Flexible and Functional
I invite you to check out β-Hydroxybutyrate: 2 Vital Role of Ketogenesis in the Brain for Dementia Prevention / Treatment. This information can be a lifesaver for some people suffering from cognitive decline. I leave you with Six Tips for a Youthful and Healthy Life as We Age.
Thank you for reading my perspectives. I wish you a healthy and happy life. I am here to help, so reach out when you need support. More stories like this are in this collection. If you wish, you may subscribe to my Health and Wellness newsletter to benefit from my decades of health, science, and technology experience.
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A Quick Update on My Recent Book Projects
To support the writing community and help them to be competitive in the market I recently authored a book titled Substack Mastery, which is now available in popular online bookstores. It was well received by readers and now it trends as a best-selling book in its categories. Here is the link to find it in different bookstores. The paperback of this book is also available through Amazon.
Yesterday, I published a new version of the Substack Mastery for busy people and explained the reasons in a new story.
How I Will Help Freelance Writers Save $600 by Condensing My Bestseller 5 Times for Them
Just like some prefer fatty cuts while others opt for lean, my goal is to cater to the unique needs of every reader.medium.com
I will continue beta reading for the next version. So, if you enjoy reading and providing feedback, here are links to chapters for free:
Preface of “Substack Mastery” for Beta Readers, Chapter 1, Chapter 2, Chapter 3, Chapter 4, Chapter 5, Chapter 6, Chapter 7, Chapter 8, Chapter 9, Chapter 10, Chapter 11, Chapter 12, Chapter 13, Chapter 14, Chapter 15, Chapter 16, Chapter 17, Chapter 18, Chapter 19…
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