For years, melatonin has been called the sleep hormone. We’ve been told it’s released by the pineal gland at night to help us drift off to sleep.
But that’s only a tiny part of the story.
In truth, melatonin is a 24-hour hormone — made mostly during the day, powered by light, and essential for hormone balance (e.g. menopause symptom relief), cellular repair, and long-term vitality.
Let’s unpack what modern science is revealing about this misunderstood hormone, and how reclaiming your natural light environment [1]may be one of the most powerful hormone-balancing tools available.
Melatonin: More Than a Sleep Hormone
Did you know that only about 5% of your body’s melatonin comes from the pineal gland at night? The rest, around 95%, is made inside your cells by your mitochondria [2] during the day, under natural sunlight.
That’s right: the hormone we associate with darkness is largely made by light!
Specifically, melatonin production is triggered by near-infrared (NIR) light, which makes up about 70% of sunlight’s energy. NIR penetrates deeply into your tissues, nourishing your brain, muscles and organs; where it helps your cells produce melatonin right where it’s needed most.
Following this, inside each cell melatonin works as an amazing “cascade antioxidant” — one molecule of it can neutralise up to 10 reactive oxygen species (ROS), protecting your mitochondria from oxidative stress (wear and tear). By contrast, a vitamin C molecule – a well know antioxidant, typically neutralises just one or two ROS.
This is what makes melatonin so powerful — it’s not just another antioxidant; it’s your body’s built-in repair signal.
The Sunlight–Melatonin–Hormone Connection
Overall, your hormones don’t work in isolation. They function as an orchestra — thyroid, cortisol, [3] estrogen, progesterone and melatonin each play a role in timing, balance, and feedback loops.
Melatonin helps coordinate this hormonal rhythm by keeping your circadian system aligned with the natural light-dark cycle. Here’s how:
- Morning sunlight sets your internal clock, boosting cortisol and alertness and signalling hormones to be released
- Daytime light, especially NIR, fuels mitochondrial melatonin, protecting your cells from daytime stress and increase energy production
- Evening darkness allows pineal melatonin to rise, calming the brain and signaling the release of growth and sex hormones overnight, allowing repair and regeneration
When this natural rhythm is disrupted, for example by spending all day indoors under LED lights, melatonin levels drop, and so does hormonal harmony. Subsequently, low melatonin can lead to:
- Fatigue and poor sleep
- Mood swings or irritability
- Irregular menstrual cycles
- Thyroid sluggishness
- Faster aging and inflammation
Your body isn’t just tired — it’s out of sync.
Why Modern Light Environments Disrupt Hormones
For millions of years, humans were bathed in full-spectrum sunlight — from sunrise to sunset, and firelight at night. That combination kept melatonin, cortisol, and reproductive hormones perfectly tuned.
Today, we’ve replaced sunlight with LEDs and screens.
While convenient, this artificial light environment lacks the NIR spectrum that stimulates mitochondrial melatonin and overloads us with blue light, which creates oxidative stress and suppresses natural melatonin release.
Consider this:
- Eight hours in an office under LED light creates as much oxidative stress as half an hour in full sunlight — but without the protective benefits of NIR
- Children spending 7+ hours daily under artificial light show measurable cortical thinning (reduced brain volume) compared to those in naturally lit classrooms
- Blue light overstimulates mitochondria, lowering their energy output and impairing hormone signaling.
In short, our modern light diet is as unbalanced as a junk-food diet — all stimulation, no nourishment.
The Daytime Melatonin Effect: Why You Feel Calm After Sunlight
Ever noticed how peaceful and sleepy you feel after a day at the beach or hiking outdoors?
That’s not just “fresh air” — it’s your melatonin response in action.
When you’re exposed to natural sunlight or physical activity outdoors, your cells experience a burst of oxidative activity. In response, your mitochondria ramp up melatonin production to neutralise that stress.
Afterward, when the oxidative demand drops, your melatonin remains elevated — creating that familiar feeling of deep calm and relaxation. It’s your body’s way of saying: “We’ve rebalanced. You can rest now.”
Melatonin and Female Hormones: The Subtle Connection
Melatonin interacts directly with many hormones — but its relationship with reproductive and stress hormones is especially important for women. Here’s what research shows:
- Melatonin modulates gonadotropin-releasing hormone (GnRH), which influences estrogen and progesterone production
- It helps regulate the timing of ovulation and menstrual cycles
- It counteracts the effects of cortisol (the stress hormone), protecting the ovaries from oxidative damage
- Low melatonin is linked with PMS, irregular cycles, perimenopausal insomnia, and hot flashes in menopause
Essentially, melatonin acts as a guardian hormone, helping maintain the delicate hormonal rhythm that supports fertility, sleep, mood, and longevity.
That’s why women often feel the impact of disrupted light cycles more profoundly — their hormonal balance depends on this rhythmic communication.
Natural Ways to Support Your Melatonin Cycle
You can’t supplement your way out of a light deficiency — melatonin tablets only mimic a small part of the equation. The real solution lies in rebuilding your light environment and lifestyle.
Here’s how:
1. Get natural light every morning
- Step outside within 30–60 minutes of waking — even on cloudy days
- Morning light helps set your circadian rhythm and stabilises cortisol–melatonin balance
2. Spend more time in shade, not just Sun
- Most near-infrared photons don’t come directly from sunlight — they bounce off trees, grass, soil, and clouds
- That’s why sitting under a tree or walking in nature still nourishes your cells
3. Train or walk outdoors
- Exercise boosts ROS, which in turn triggers more mitochondrial melatonin — a built-in antioxidant system
- Outdoor training combines the benefits of movement and light
4. Create darkness at night
- Use warm lighting after sunset — amber or red bulbs if needed
- Avoid bright bathroom or phone lights if you wake up during the night
- Aim for 8–10 hours in true darkness to let pineal melatonin do its job
5. Reconsider your indoor lighting
- Replace LEDs with incandescent or halogen bulbs where possible — they emit more infrared light
- Use lamps instead of overhead lighting in the evening
6. Support nutritional pathways
- Eat foods rich in tryptophan and vitamin B6 — the building blocks for melatonin: turkey, eggs, nuts [4], seeds [5], leafy greens [6]
- Balance blood sugar and avoid late-night meals to keep hormonal rhythms steady and keep weight off [7]
The Bottom Line: Melatonin is the Molecule of Light
In summary, we often think of melatonin as the “hormone of darkness.” In reality, it’s the molecule of sunlight — made in your cells during the day, under natural light, to defend against oxidative stress and support hormone balance.
When you restore your relationship with light, everything changes:
- Energy rises
- Sleep deepens
- Mood stabilizes
- Hormones re-sync naturally
Just like vitamin C deficiency once caused scurvy, today’s epidemic of fatigue, insomnia, and hormonal imbalance may reflect a deficiency in sunlight — particularly near-infrared light.
So before reaching for another supplement, start with the simplest, most natural medicine of all:
☀️ Rebuild your light environment. Let nature reset your hormones from the inside out.
Key Takeaways
- Only 5% of melatonin comes from the pineal gland — the rest is made in your mitochondria during the day under sunlight
- Melatonin acts as your body’s most powerful antioxidant and hormone synchroniser – it truly is a free and effective natural menopause treatment
- Modern light exposure (LEDs, screens, indoor living) drastically reduces melatonin and disrupts hormones
- Natural light, darkness at night, balanced nutrition, and outdoor time can restore your melatonin rhythm and hormonal harmony
The fascinating melatonin story continues in the next blog when I’ll translate the science into action — how to support melatonin production naturally (light, nutrition, timing, habits), how this supports hormone balance (thyroid, cortisol, estrogen), and practical steps to protect circadian health. The link will be provided here once the blog is published.
I bet that by reading this blog you’ve discovered many new things about melatonin and its importance for healthy body and mind. Comment below if you have questions or comments.
Do you need help with syncing your lifestyle and nutrition with natural rhythms? I’m an experienced wholistic online naturopath or nutritionist [8] helping clients based anywhere in Australia so, please get in touch. You can Book an online consultation now [9] or click on the button below to book a free 15-minute initial discussion to talk about your circumstances and how I can help.
[9]I look forward to helping you get better health and wellbeing soon!
Best of Health
[10]
Joanna Sochan
Wholistic Health and Lifestyle Therapist
Natural and Lifestyle Therapies for Abundant Health and Wellbeing
References
Atkinson, R. C., Skene, D. J., & Arendt, J. (2011). Melatonin and the human circadian system. Journal of pineal research, 51(1), 1-10.
Burgess, H. J., & Eastman, C. I. (2004). Circadian rhythms and shift work. Occupational medicine, 54(4), 213-218.
Brzezinski, A. (1997). Melatonin in humans. New England Journal of Medicine, 336(3), 186-195.
Chang, A. M., Aeschbach, D., Duffy, J. F., & Czeisler, C. A. (2015). Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proceedings of the National Academy of Sciences, 112(4), 1265-1270.
Chida, Y., & Steptoe, A. (2009). The effect of psychological stress on the human immune system. Journal of behavioral medicine, 32(1), 6-18.
Dubocovich, M. L., & Comai, C. (2004). Melatonin receptors. Cell and tissue research, 315(1), 1-18.
Driver, H. S., & Taylor, S. E. (2000). Exercise and sleep. Sleep medicine reviews, 4(4), 229-251.
Herxheimer, A., & Petrie, K. J. (2010). Melatonin for the prevention and treatment of jet lag. Cochrane database of systematic reviews, (4).
Hogben, C., & Finn, J. D. (2019). Melatonin and sleep. The Lancet, 393(10168), 156-168.
Lissoni, P., Barni, S., & Maestroni, G. J. (1997). Melatonin and the immune system. Neuroimmunomodulation, 4(4), 221-231.
Lissoni, P., Barni, S., & Maestroni, G. J. (1999). Melatonin and cancer: an update. International journal of cancer, 84(4), 559-564.
Manchester, J. C., Cagnon, L., & Gitto, E. (2015). Melatonin and cardiovascular disease. Current pharmaceutical design, 21(35), 5141-5150.
Okatani, Y., Deguchi, T., & Okawa, M. (2005). Melatonin production in the human pineal gland and its regulation by the suprachiasmatic nucleus. Journal of pineal research, 39(1), 1-11.
Reiter, R. J., Tan, D. X., & Singletary, K. W. (2016). Melatonin and cancer: an update. International journal of cancer, 138(11), 2527-2542.
Srinivasan, V., Pappas, A., & Srinivasan, K. (2016). Melatonin: a neuroprotectant and neurogenesis stimulator. Journal of pineal research, 61(2), 213-224.
Additional resources
- Sunlight as medicine: sleep, mood, hormones and metabolism [11]
- Artificial light vs sunlight: the hidden impact on your health [12]
- How to reset sleep patterns and circadian rhythms [13]
- Food and home remedies for deep sleep [14]
Disclaimer: The above material is for informational and educational purposes only. It should not be used to self-diagnose and it is not a substitute for a medical advice, diagnosis, treatment, prescription or recommendation. All viewers of this content, especially those taking prescription or over-the-counter medications, should not make any changes in their health regimen or diet before first consulting a doctor or other qualified health provider with any questions they may have regarding a medical condition or their particular circumstances.
Joanna Sochan is a Natural & Lifestyle Therapist and founder of Naturimedica Wholistic Wellcare. She has a passion for helping clients transform their lives by becoming healthy and well naturally. Joanna has 15 years experience in clinical practice and has special interest in solving complex cases, gut health, food sensitivities, hormone imbalances (menopause), senior health (bone health and osteoporosis) and weight loss. She helps clients individually (mostly online) Australia-wide and also offers online therapeutic programs, eCourses and self-help eBooks. View full bio [15].