The Truth and Dangers of Melatonin — And the Smarter Alternative You Haven’t Heard About

Our skin is more than a surface. It’s the largest organ in the body - responsible for absorbing nutrients, regulating temperature, and acting as a direct line into your bloodstream.

As toxicologist Dr. Philippa Darbre has shown in her work, what we put on our skin can enter the body and affect our internal systems - including hormone function. So when we apply something topically, it matters.

That’s why we’re talking about melatonin today.

In June 2025, Associate Health Minister David Seymour announced that melatonin will soon be available over the counter in New Zealand pharmacies. While this makes sleep aids more accessible, it also raises critical questions. Melatonin is not a vitamin, mineral, or herbal extract. It’s a lab-made synthetic hormone that influences your body’s entire endocrine system.

Melatonin use has already surged in New Zealand. Ministry of Health data shows that prescriptions for melatonin increased sharply in recent years, especially among children with autism and ADHD — with 19% of autistic children, 22% of children with ADHD, and 30% of children with both being dispensed melatonin through the health system.

Before you reach for it, here's what the science says.

1. Melatonin Is a Hormone - Not a Vitamin or Natural Supplement

Melatonin is produced by the brain’s pineal gland to regulate your sleep-wake cycle. But the version in supplements? It’s almost always synthetic, produced in labs from petrochemical derivatives like phthalimide or tryptophan analogs. These compounds undergo chemical reactions to create a molecule that mimics your body’s own melatonin.

Historically, melatonin was sometimes extracted from animal pineal glands, especially cows. These bovine-derived formulations are now banned in many countries due to safety concerns, including the risk of contamination from diseases like BSE (mad cow disease). Today’s melatonin is synthetic, but still not plant-derived or truly “natural.”

Some products claim to be "natural" or plant-based, but true plant-derived melatonin is only found in trace amounts in foods like cherries or rice. There is no commercial extraction process for these sources at useful dosages.

Reference: Reiter et al., Frontiers in Endocrinology (2017)

2. Taking Melatonin Can Suppress Your Own Production

Your body operates on a feedback loop. When you supplement with melatonin, especially at high or regular doses, it may reduce your own natural production - making it harder to sleep without it.

Over time, this may disrupt your circadian rhythm and lead to dependency.

Reference: Arendt J., New England Journal of Medicine (2000)

3. It Can Disrupt Hormones and Reproductive Health

Melatonin isn’t just involved in sleep. It interacts with hormones that influence puberty, menstruation, fertility, and thyroid function.

That’s why international experts advise caution in:

• Children and teens
• Women trying to conceive
• People with hormone-sensitive conditions

Reference: Kennaway D., Journal of Paediatrics and Child Health (2015)

4. What Happens When You Take Melatonin Orally?

• Fast spike, short effect: Oral melatonin is rapidly absorbed (peak at 30–60 mins), but has a short half-life.
• Low bioavailability: Up to 90% may be lost through the gut and liver.
• Drug interactions: Melatonin is processed through the CYP1A2 liver enzyme pathway, which also processes many antidepressants, blood pressure medications, antipsychotics, contraceptives, and blood thinners. Taking melatonin alongside these drugs can alter their effectiveness or increase side effects.

Reference: Zhdanova et al., JCEM (1998); Di et al., Life Sciences (1997)

5. Side Effects Are Common

Despite being labelled "natural," melatonin use is often associated with:

• Grogginess or brain fog
• Headaches
• Vivid dreams or nightmares
• Mood changes
• Hormonal imbalances
• Dizziness or nausea

Reference: Pandi-Perumal et al., Current Neuropharmacology (2007)

6. It Can Build Tolerance Over Time

Many people report that melatonin "stops working." That’s because repeated use can lead to tolerance, requiring higher and higher doses for the same effect.

This is not a sustainable or safe sleep strategy.

Reference: Ferracioli-Oda et al., Sleep Medicine Reviews (2013)

7. Not Approved for Long-Term Use in Many Countries

In the UK and EU, melatonin is a prescription-only medicine, generally used for short-term treatment of sleep disorders. It is not sold freely due to its hormone-altering effects.

NZ's approval is new and still evolving — and we believe consumers deserve full transparency.

8. There Are Safer, Natural Alternatives -  But Not All Magnesium Is Equal

Magnesium is a mineral your body needs daily. It helps activate GABA, the neurotransmitter responsible for calming the nervous system.

Topical magnesium avoids the gut, is fast-absorbing, and works without impacting hormones.

Unlike melatonin, it's:

• Non-hormonal
• Suitable for nightly use
• Safe for children (4+), perimenopausal women, and sensitive individuals
• Part of an advanced sleep-support formula that includes magnesium plus calming botanicals like valerian, hops, and passionflower
• Designed for fast absorption and gentle delivery — without synthetic fragrance or hormone disruptors

Not all magnesium products are created equal. Many cheaper brands use lower-quality sources or basic formulas that lack the complementary ingredients needed to calm the nervous system and prepare your body for deep rest.

Surmanti’s Magnesium Sleep Support Spray is Magnesium 2.0 — a next-generation formula designed for real results. Made in New Zealand, backed by science, and trusted by hundreds and award-winning.

Melatonin vs Magnesium: A Clear Comparison

Feature	Oral Melatonin	Surmanti Topical Magnesium
Type	Synthetic hormone	Natural mineral (not hormonal)
Mode of Action	Spikes melatonin to induce sleep	Supports GABA, calms nervous system
Absorption	Oral → Gut → Liver	Transdermal → Bloodstream
Half-life	Short (30–60 mins)	Gradual, steady
Hormonal Effects	May suppress natural melatonin	Hormone-free
Side Effects	Grogginess, mood swings	None reported
Tolerance Risk	High	Low
Medication Interactions	Yes	Minimal
Use Case	Jet lag, short-term fix	Nightly, long-term sleep support

Bottom Line

Melatonin may have its place for jet lag or short-term disruption. But for most people, it’s not a sustainable long-term solution.

If you want something that works with your body, supports your sleep, and keeps your hormones in balance — topical magnesium is the smarter, healthier choice.

Click HERE to view our Magnesium Sleep Support Collection

Frequently Asked Questions

I’m on antidepressants and was prescribed melatonin, but I felt worse — is that why?
It’s possible. Melatonin is processed through the same liver enzymes (CYP1A2) as many antidepressants. This can affect how either substance is metabolized, sometimes intensifying side effects like mood swings, fatigue, or hormonal imbalance. If you felt worse, it may be due to how melatonin interacted with your medication or your body’s sensitivity to hormonal disruption. Switching to a non-hormonal option like topical magnesium may be a better fit — and always speak with your prescribing doctor before making changes.

How do I switch from melatonin to magnesium?
If you've been using melatonin regularly, it’s best to transition gradually. Begin by using topical magnesium at night (ideally after a warm shower) while slowly reducing melatonin over 1–2 weeks. This allows your body to re-establish its natural melatonin rhythm while receiving the calming support of magnesium. Some users find success alternating every other night before fully switching.

What if it doesn’t work for me?
Every body is different, and some people may take longer to respond to magnesium than others — especially if your sleep cycle has been disrupted for a long time. That’s why we recommend using Surmanti’s Magnesium Sleep Support consistently for 2 to 4 weeks, ideally after a warm shower to maximise absorption. If it’s not the right fit for you, we offer a 100% Love It or Your Money Back Guarantee.  

Is melatonin natural?
No. While your body makes melatonin naturally, the kind found in supplements is typically synthetic, produced in a lab from petrochemical ingredients.

Can melatonin become addictive?
Not chemically, but it can cause psychological dependence, especially if used nightly. Your body may stop producing its own melatonin.

What are the side effects of melatonin?
Grogginess, headaches, vivid dreams, mood swings, dizziness, and hormone disruption. It may also interact with medications.

Can I take melatonin with other medications?
Melatonin is processed by the same liver enzymes (CYP1A2) that metabolize many antidepressants, blood pressure meds, and hormonal contraceptives. Always check with your doctor.

Is topical magnesium safe for children?
Yes. Surmanti Magnesium Sleep Support Spray is safe for children aged 4 and up, and is a hormone-free, gentle alternative to melatonin.

How long does it take for topical magnesium to work?
Most users feel calmer within 15–30 minutes. For best results, use consistently for 2–4 weeks.

Further Reading

• Whelan A.M. et al. (2009) Nutrition Reviews
• Reiter R.J. et al. (2010) Current Topics in Medicinal Chemistry
• Brzezinski A. (1997) New England Journal of Medicine
• Darbre P.D. (2003) Journal of Applied Toxicology