Magnesium has more clinical sleep evidence than almost any other supplement you can buy without a prescription.
Three controlled trials · 17 minutes faster to sleep.
60 servings. About $0.93 per night
Brain firing, body running hot, lying still in the dark. By 5am you've made a list of everything you forgot last week.
By 7am you're up, tired in a way coffee doesn't touch, deciding which of today's meetings you can fake your way through.
Most GPs will tell you it's stress. It isn't.
One specific thing is happening in your body, and one of those symptoms has an answer backed by more clinical evidence than almost anything else you can buy without a prescription.
For most women, the worst sleep happens in perimenopause, when oestrogen swings unpredictably from week to week. That's why your symptoms feel erratic. They are.
This is not stress. It's not a sleep hygiene problem. It's a neurochemical shift, and it doesn't reverse on its own.
It supports GABA signalling, the calming system your brain uses to wind down. It also helps regulate cortisol, the stress hormone that's supposed to drop at night but doesn't reliably drop anymore.
But for the sleep part, the clinical evidence is unusually specific.
Three randomised controlled trials. Older adults with insomnia. Daily magnesium or placebo.
That sounds small until you're the one lying awake. Over a week, it's almost two hours of sleep you didn't used to get.
In older adults with insomnia, magnesium supplementation produced significant improvements in four sleep markers at once: faster sleep onset, reduced insomnia severity, higher melatonin, lower cortisol.
A 2025 trial using a chelated form of magnesium (bisglycinate) showed a modest but statistically significant improvement in insomnia scores. Biosphere uses a different chelate (lysinate glycinate) in the same family.
The trials that moved sleep markers used 300 to 500mg of elemental magnesium a day. Most chemist magnesium is 150 to 250mg. A lower dose isn't a smaller version of the same effect. It's often below the threshold where any effect shows up at all.
Form matters too. Magnesium oxide, the cheapest and most common form, showed no difference from placebo in a randomised double-blind trial. Chelated forms (the kind bound to an amino acid) and citrate both raised blood magnesium meaningfully.
New Zealand's most reviewed magnesium • 150+ stores nationwide
If you don't feel a difference, you get every dollar back. No forms. No questions asked. Just email us.
About $0.93 per night. Two months supply
Choose your flavour:
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New Zealand's most reviewed magnesium · 150+ stores nationwide
Overall rating: 4.8 / 5 from 1677 reviews.
Astaxanthin is vital for us all in this aging process. Every blessing we can get for all round health and optimal function is a bonus. We are grateful for the bioavailable source. Regards Steve and Fiona
I have tried many supplements over the years. Some I’ve stopped using because I didn’t notice a difference. I Will always aim to keep astaxanthin as part of my stack. I have noticed such an amazing change in my skin. My skin has always been good, but this has taken it to another level. I love this product! I particularly love the Biosphere brand as they use olive oil in the capsules, rather than seed oils. Really happy to support this NZ company.
Great product, I have been using it to help my eyes feel more comfortable ( post menopause) , they are definitely less scratchy than they were! I can’t wait to try the magnesium yet, it looks really good.
We both have the best sleep usimg this product. I am about to put in another order.
Lovely flavour and works really well.
I rely on 'Sleep' to help my sleep. Its a vial part of my evening ritual. I notice when I dont take it
Great for dry eyes. Best I've tried
Take this every night for restless legs and sleep . Alternate between the 2 flavours
Very good product but I did have to adapt it. I found taking it just before bed it would give me a hit of energy. So I no take it with dinner or just after around 7 and it gives my body time to process the ashwaganda. I still do have trouble sleeping but I do feel the nights I do sleep it’s a deeper sleep. I am going through a lot of stress and biological changes but I do feel it has helped just not as much as I hoped. The flavour is delicious and the customer service was awesome. I’m going to try the plain magnesium next time as I think ashwagandha not well suited to me
Great product - slept soundly :)
I’m loving this quality magnesium product from BioSphere as it has transformed the quality of my sleep.
I was sceptical but desperate when I started using Gut Support. After the first month, there hadn’t been a huge change, but I decided I was going to give it 2 months. Only a week into the second tub I noticed a definite change, and after not quite 2 months my system is so much calmer and more regular - the best it has been in nearly 6 years.
Nerve pain gone , deep sleeps after taking this . ! I am about to reorder , thanks guys 😍
This has been a game changer for me . It has eased pain and cramping at night . It promotes a feeling if calm and relaxation . I will never stop using this . Please buy it . I promise you won’t be sorry . Carolyn
Just love this product. I am on my third tin. I have been able to halve my blood pressure medication.
Sleep so much better and no more cramps
I won't need to ask for my money back. It works! The quality of my sleep has improved 10 fold.
Helps me stay asleep all night long
Prompt delivery and high quality. Noticed my eyesight not troubling me as much within a week.
It was a tough winter but this Biosphere Immune got us through.
I began taking this product 2 weeks ago to help with my sleep due to RLS and aching muscles due to injuries. Its great. I fall asleep well and sleep longer. I love the lemon lime flavour too!
Great quality astaxanthin and an easy addition to my daily supplement routine. I take it for its antioxidant, skin and general healthy-ageing benefits. Simple, well-dosed and no fuss. Very happy with it.
Awesome product!
Love it
Really like the flavour and taste, it encourages me to use it daily !
My husband and I have both been taking Biosphere Nitric Oxide, and we’ve been really happy with how we feel since starting it. We both feel so much better overall and have noticed a real difference in our general well-being and energy. It’s now become part of our daily routine, and based on our personal experience, we’re very pleased with it. It’s not often that we find a product that we both feel has made a noticeable difference, but this one has. We’ll definitely continue taking it!
Another one bites the dust! I’m really benefiting from taking this product every evening. I’m sleeping through the night, and waking refreshed. I would recommend this to anyone as a fuss free, easily digestible form of magnesium for settling your nervous system and allowing good sleep patterns.
Really like the Biosphere Magnesium. It's so helpful before and after hard physical work when I tend to get plagued with cramp. Alongside other salts & good hydration it's been great .Also very pleasant to drink. My wife also likes to use it at night for restless legs & to help relax. 😊
I love this product. I noticed an improvement in my skin. Looks and feels so much smoother.
I have systemic health issues and this is great for sleep, nerves and digestion (in a slow moving system). Great combination of types of magnesium. Easy to mix and take.
Great product. I take it every morning 🙂
Having parkinsons disease, exercise is very much my medication but has consequences the magnesium helps with the cramps and sleep quality which makes tomorrow better.
Love this product, after my first month I have far more mobility, energy and stamina, will be purchasing more...
I haven't gotten my very first bottle yet, but I will be ordering more. Capsules are easy to swallow, and makes it easy that need to take with food . Easy to remember with breakfast
It’s one of those things that you don’t you don’t know what you’ve got ‘til it’s gone! I was sleeping well and didn’t notice my gym recovery was good until I ran out of magnesium! Without it, my sleep is terrible and I’m sore for days after working out. Ordering more now!
On my second month of astaxanthin, not much change except a little more energy generally. Will give it a full three months.
I am so happy with my Astaxanthin . Can’t believe that it has worked so quick at pain relief . I have tried lots of other products in many years and I think this is the best thing I have tried . I have no pain and it so good . I hope this keeps up I have arthritis and and a few joint replacements so always in pain . Thank you
Awesome flavour magnesium for a massive day in the mountains!!!
Both flavours are nice and the powder mixes well. No longer getting night time cramps, so very happy with this. Will definitely be continuing with this product.
Awesome product.
Try Biosphere Magnesium for 60 nights. If your sleep hasn't changed, email us. We'll refund you in full. No forms, no returns.
Magnesium works on two of the sleep systems oestrogen disrupts: GABA signalling and cortisol rhythm. It doesn't fix hot flushes or reverse menopause. What it does is give you back the body chemistry that lets you wind down and stay asleep. For the sleep part, that's where the strongest evidence sits.
Most women notice shifts within one to two weeks. Full effect builds over about four weeks. The clinical trial we cite used daily magnesium for eight weeks. If nothing has changed by week four, the 60-day money-back guarantee has you covered.
Check with your GP before combining any supplement with prescription medication, including HRT. Magnesium is generally well-tolerated alongside most prescriptions, but your doctor knows your full picture. Standard advice, not a red flag about the product.
No. Magnesium isn't a sedative. It supports the systems that let your body wind down on its own, so there's no next-day hangover. Different from melatonin. Very different from prescription sleep aids.
Yes. Magnesium isn't habit-forming. Your body doesn't build tolerance the way it does with sleep medication, and any excess is excreted in urine. It's a mineral, not a drug, so there's no need to cycle off or take breaks. Most of our customers take it nightly for months or years. If you have kidney disease or take prescription medication, check with your GP before starting.
Yes, our magnesium is suitable for diabetics. We only use stevia leaf extract and monk fruit extract for sweetness.
You've read the mechanism. You've seen the evidence. You know what magnesium does and what it doesn't. The only thing left is 60 nights to find out.
