Melatonin is far more than a sleep hormone. It plays a central role in circadian rhythm, [1] mitochondrial health, immune balance, and hormone regulation – particularly during perimenopause and menopause. This melatonin and circadian rhythm guide briefly explains how sunlight, modern lifestyle factors, and hormonal changes influence melatonin, and how to support melatonin production and healthy circadian function naturally.
What Is Melatonin (Really)?
Melatonin is a hormone and powerful antioxidant involved in:
- Circadian rhythm regulation
- Cellular and mitochondrial protection
- Immune modulation
- Hormonal signalling
While commonly associated with sleep, most melatonin is produced during the day [2]and released at night in alignment with the body’s internal clock. Only 5% of melatonin is produced at night by the pineal gland, approximately 95% comes from multiple tissues throughout the body and is synthesised in the mitochondria of these cells.
How Sunlight Regulates Melatonin
Sunlight regulates melatonin production by influencing the body’s circadian rhythm. Exposure to light, especially in the morning, suppresses melatonin levels, signalling the body to be alert and active, while darkness increases melatonin production, preparing the body for sleep. Sunlight exposure – especially in the morning – influences:
- Serotonin production
- Circadian entrainment
- Healthy night-time melatonin release
Key light inputs include:
- Blue light (circadian timing setting, blue light suppresses melatonin production – especially at night)
- Red and near-infrared light (NIR – mitochondrial support)
Melatonin, Sleep and Ageing
As we age, melatonin rhythms can become disrupted due to:
- Reduced daylight exposure
- Increased artificial light at night
- Hormonal changes
- Chronic stress and inflammation
This can contribute to:
- Insomnia
- Early waking
- Non-restorative sleep
Why Melatonin Matters After 40
During perimenopause and menopause, shifts in:
- Estrogen
- Progesterone
- Cortisol
can directly affect melatonin production and signalling, increasing vulnerability to sleep, mood, and metabolic challenges. This melatonin and circadian rhythm guide highlights changes that happen in midlife transition.
Common Causes of Melatonin Disruption
- Inadequate morning sunlight and also during the day
- Excessive evening light exposure
- Shifted sleep–wake timing
- Chronic stress and inflammation
Foundational Ways to Support Healthy Melatonin
- Morning outdoor light exposure
- Consistent sleep–wake timing
- Evening light hygiene
- Nervous system regulation
- Nutrient sufficiency – tryptophan, an amino acid found in foods like turkey, fish, eggs, and dairy; as well as magnesium [3] and vitamin B6.
When Supplements May Help
Melatonin supplements may be useful short-term in select cases, but they do not replace circadian foundations and should be only used thoughtfully.
Key Takeaways
- Melatonin is primarily a daytime-produced hormone
- Sunlight is essential for healthy melatonin rhythm
- Midlife hormonal shifts can disrupt melatonin e.g. sleep problems in menopause
- Circadian support matters more than supplements
Related Deep-Dive Articles
If you’d like to learn more about the natural melatonin cycle and circadian rhythms, I wrote a series of in-depth and practical blogs to explain why they have key importance to health and wellbeing for everyone.
- Melatonin: The hidden daytime hormone that powers your hormones [4]
- Rebuilding Your Natural Melatonin Cycle: Practical strategies for hormonal harmony [5]
- Morning Sunlight: The key to your body clock [6]
- Sunlight as Medicine: Sleep, mood and metabolism [7]
- Artificial Light vs Sunlight: The hidden impact on your health [8]
Next Steps
If you’re unsure how this information applies to your own health, individual support can make all the difference. I offer online consultations for Australia-based clients.
👉 Learn More About Consultations [9]
Using information is different from applying it. Education is an important first step – and you’re already doing that. If you’re ready for guidance that takes your unique health history into account, I’m here to help.
I work virtually as an online wholistic naturopath and nutritionist [10] helping clients based anywhere in Australia. Book an online consultation [11] or click on the button below to book a free 15-minute initial discussion to talk about your circumstances and how I can help.
[11]I look forward to connecting with you and to working with you towards better health and wellbeing!
Best of Health
Joanna Sochan
Wholistic Health and Lifestyle Therapist
Natural and Lifestyle Solutions for Abundant Health and Wellbeing
Related posts
- Top sleep enhancing nutrients: inositol and L-theanine [12]
- Preventing weight gain in menopause [13]
- Holy basil: key herb for stress, anxiety, depression and fatigue [14]
Disclaimer: The above material is for informational and/or 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 Wholistic Natural Therapist and founder of Naturimedica Wholistic Health & Wellcare. She has a passion for helping her 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, detox and weight loss. She helps clients individually (mostly online) Australia-wide and also offers online therapeutic programs, eCourses and self-help books. View full bio [15].