Marine Magnesium with Potassium

An excellent source of natural bioavailable magnesium to assist with sleep, heart and general health.
  • Support cardiovascular, brain and muscle health
  • Balance blood sugar, pressure and heart rhythm
  • Promote longer sleep
  • Learn More
    $19.95 AUD (Incl Tax)
    30 Day Supply | Size: 60 Capsules

    Free shipping on orders over $100. Find shipping details here

    Why Do You Need Magnesium?

    Magnesium is one of the most important minerals in the body and is a co-factor for over 300 processes ranging from energy, nerve and muscle function to digestion, stress and sleep:

    Sleep and Stress Levels

    Sleep and Stress Levels

    Feeling stressed and finding it hard to sleep? Magnesium is a natural relaxant, helping regulate stress hormones such as cortisol.⁴ It also promotes production of melatonin, the hormone responsible for deep and restful sleep.⁵

    Brain Health

    Brain Health

    Magnesium may help improve memory, learning ability, and delay the brain shrinkage that happens as a natural part of aging.² Deficiency has been associated with chronic diseases, including migraine headaches, Alzheimer’s and strokes.³

    Heart Health

    Heart Health

    Magnesium is good for muscles, especially the heart. It has been associated with regulating heart rate and managing the risk of everything from hypertension to metabolic syndrome and type 2 diabetes.¹

    Not all Magnesium is Created Equal

    Magnesium comes in a variety of forms and, as with most supplements, some are more effective than others.

    Our researchers reviewed all the available forms and finally selected one which we believe is the most easily absorbed and beneficial for the body.

    It’s called Aquamin MG®, and is extracted from pure seawater off the coast of Ireland. Apart from it being high in elemental (pure) magnesium and highly bio-available it contains another 72 trace elements which are also beneficial for human health.

    Several of the trace elements in Aquamin, such as magnesium, copper, zinc, manganese and selenium, are recognised as important regulators of inflammation, and Aquamin has also been linked to benefits for everything from digestion to muscle health, stress and immunity

    Download this clinical study on magnesium for the science behind this specific formulation.

    Magnesium – You Might Not Be Getting Enough


    A Natural Relaxant for Stress and Sleep

    Stress can cause the body to release cortisol, which can increase heart rate and blood pressure, and trigger the fight or flight response. This can lead to feelings of anxiety, nervousness and even panic.

    Magnesium helps to reduce the production of stress hormones like cortisol and promotes the release of feel-good neurotransmitters like serotonin and dopamine.

    In addition to regulating stress levels, studies have shown that magnesium may help to improve sleep quality by reducing the time taken to fall asleep, increasing how long your sleep for and reducing the number of times you wake up in the night. It does this by regulating the body's production of the sleep hormone melatonin, which is responsible for promoting deep and restful sleep.

    Brain Boosting Mineral

    Research has shown that magnesium supplementation may improve cognitive function, memory and learning ability in both animals and human. For example, it helps maintain healthy brain cell communication by regulating neurotransmitters, such as serotonin and dopamine which are responsible for mood, memory and learning.

    It also works for your brain heath by being the gatekeeper of the N-methyl-D-aspartate (NMDA) receptors which play a critical role in the regulation of learning, memory and the ability to change and adapt in response to new experiences. The magnesium sits inside these receptors, preventing them from over stimulation. Over stimulation may kill nerve cells, and in turn, may cause brain damage.⁷ 

    Brain inflammation may impair brain function and contribute to cognitive decline and magnesium has been shown to help reduce it. This is one reason it has been found to have a protective effect against age-related cognitive decline and neurological disorders such as Alzheimer's and Parkinson's disease.

    Magnesium deficiency has been linked to various neurological conditions such as migraines, depression, anxiety and ADHD. It has been suggested that magnesium supplementation may be beneficial in the treatment of these conditions. 

    Say Goodbye to Heart Aches and Muscle Pain

    Ok, it won’t fix that type of heart ache, but magnesium is essential for the proper working of all the muscles in the body, including the heart.

    Regulate Heart Rhythm - Magnesium helps your heart muscle by countering calcium which stimulates contractions. Because these two minerals compete with each other, the magnesium helps ensure the heart cells are not overstimulated and you maintain a regular heartbeat.  

    Magnesium and Diabetes - Magnesium helps regulate insulin and moves sugar out of the blood and into the cells for storage. Various short-term studies have shown that magnesium has significantly helped reduce fasting blood sugar levels in type 2 diabetics. Longer term studies are still needed to be conclusive.

    Healthy Blood Pressure - Magnesium helps regulate blood pressure by acting as a natural calcium channel blocker. This means that it can help dilate blood vessels and improve blood flow, which in turn can help lower blood pressure. Additionally, magnesium can help relax the smooth muscles in blood vessel walls, further contributing to the maintenance of healthy blood pressure levels.

    Muscle Pain - Magnesium helps with muscle problems by regulating the balance of calcium and potassium in the body, which are essential minerals for muscle contraction and relaxation. It also helps prevent muscle spasms by reducing lactic acids in muscles. It also helps reduce inflammation in muscles, promoting faster recovery from injury or overuse.  

    The Case for Potassium

    In the case of Potassium, only around 2% of Americans get enough of this essential mineral which works in synergy with Magnesium. We have included 110mg of elemental Potassium in this formula.

    Unlike Magnesium, which our bodies need a significant amount of every day, we do not need a lot of Potassium, but it is crucial for cardiovascular health and other functions in the body. Most people are potassium deficient which is why we have included Potassium in the formula.

    Who is at Most Risk?

    As we said above, half of adults are not getting enough magnesium to meet their daily requirements. For many, this might mean they are experiencing low levels of stress, discomfort and tiredness, but for those who are severely lacking, the problems can get more serious. 

    Magnesium deficiency is common in people with gastrointestinal diseases (including Crohn’s and those who are gluten-sensitive, type 2 diabetic and alcohol dependent).  Older adults in general are at risk because they are less able to absorb magnesium and may also be taking medications that may interfere with magnesium uptake.⁸

    The Natural, Pure, and Effective Way to Boost Your Magnesium Intake

    Magnesium is critical for heart and brain health, to regulate stress and to promote deep sleep. But 1 in 2 adults don’t get enough just from the food they eat. That’s why an increasing number of our customers are benefitting from Marine Magnesium with Potassium. It’s highly bioavailable, and rich in elemental magnesium, potassium and other trace elements with proven benefits for natural health.


    1. Reference: Rosique-Esteban N, Guasch-Ferré M, Hernández-Alonso P, Salas-Salvadó J. Dietary Magnesium and Cardiovascular Disease: A Review with Emphasis in Epidemiological Studies. Nutrients. 2018;10(2):168. Published 2018 Feb 1. doi:10.3390/nu10020168

    2. Reference: Alateeq, K., Walsh, E.I. & Cherbuin, N. Dietary magnesium intake is related to larger brain volumes and lower white matter lesions with notable sex differences. Eur J Nutr (2023).

    3. Reference: Stella Lucia Volpe, Magnesium in Disease Prevention and Overall Health, Advances in Nutrition, Volume 4, Issue 3, 2013, Pages 378S-383S, ISSN 2161-8313,

    4. Reference: Cuciureanu MD, Vink R. Magnesium and stress. In: Vink R, Nechifor M, editors. Magnesium in the Central Nervous System [Internet]. Adelaide (AU): University of Adelaide Press; 2011. Available from:

    5. Reference: Arab A, Rafie N, Amani R, Shirani F. The Role of Magnesium in Sleep Health: a Systematic Review of Available Literature. Biol Trace Elem Res. 2023;201(1):121-128. doi:10.1007/s12011-022-03162-1

    6. Reference: DiNicolantonio JJ, O'Keefe JH, Wilson W. Subclinical magnesium deficiency: a principal driver of cardiovascular disease and a public health crisis [published correction appears in Open Heart. 2018 Apr 5;5(1):e000668corr1]. Open Heart. 2018;5(1):e000668. Published 2018 Jan 13. doi:10.1136/openhrt-2017-000668

    7. Reference: Hou H, Wang L, Fu T, Papasergi M, Yule DI, Xia H. Magnesium Acts as a Second Messenger in the Regulation of NMDA Receptor-Mediated CREB Signaling in Neurons. Mol Neurobiol. 2020;57(6):2539-2550. doi:10.1007/s12035-020-01871-z

    8. Reference: Magnesium fact sheet by the National Institutes of Health (NIH) Office of Dietary Supplements (ODS)

    Servings per bottle: 30 (2 capsules per day) / 60 (1 capsule per day)
    Daily serving: Adults - 2 capsules per day. Children (9-18) - 1 capsule per day.

    Take 2 capsules per day. For best results take after an evening meal. 

    Combines well with Total Balance products.

    If you are taking CX8 we do not recommend that you take CX8 and Marine Magnesium with Potassium at the same time. This is because Magnesium may affect the efficacy of the Vitamin K2 ingredient which is present in CX8. Take CX8 in the morning if possible, as this increases your energy and then take the Magnesium at bedtime as it helps with sleep.

    If you are pregnant, lactating or taking any medications, please consult your health practitioner before starting new supplements.

    If you have any questions, please contact us at

    Supplement Facts

    Serving size: 2 Capsules
    Servings per container: 30
    Amount Per Serving   % DV*
    Total Carbohydrate <1g <1%
    (from 1600mg of AQUAMIN Mg® Magnesium Hydroxide from sea water)

    530 mg

    (from 300mg of Tri-Potassium Citrate)
    110 mg 2%

    Other Ingredients: Capsule (Hydroxypropylmethyl Cellulose, Water), Gum Arabic.

    If you are pregnant, lactating or taking any medications, please consult your health practitioner before starting new supplements.


    Why have you added Potassium?

    The cardiovascular system needs Potassium and most people have a minor deficiency in Potassium. That is why a small amount of Potassium was added.

    What is the dosage of the Magnesium?

    We recommend two capsules a day. 

    Can I take half dose?

    Yes, you could but you may not feel the full benefits as you would when taking the recommended dose.

    Will there be any interactions with prescription medication?

    There could be with some medication but unlikely. As usual, check with your Doctor.

    What form of Magnesium is it?

    It is a marine form derived from sea water so it has other beneficial trace elements included as well.

    I get cramp and restless legs, will Magnesium help?

    Magnesium is well known to help with these issues.

    Will it help me sleep?

    Most people find that having magnesium supplements after dinner does indeed help with restful sleep.

    What does Magnesium do?

    Magnesium support hundreds of different bio-chemical reactions in the body. The range of benefits are staggering from supporting nerve and muscle function, keeping the heart beat steady and even helping adjust blood glucose levels.

    What does Potassium do?

    Potassium helps support Magnesium but on its own it plays an important role for your heart and like magnesium supports your nerves and muscles.

    Can I take your Magnesium when I am taking a supplement of yours that contains Magnesium? Will I overdose?

    No, not at all. The levels of magnesium are quite low in our other supplements primarily due to the fact that magnesium is a bulky material.

    Are there any side effects of this product?

    No negative ones if taken at the correct dosage.

    Is Magnesium good for mood?

    Yes, this is a significant benefit of magnesium. There have been many studies that have shown magnesium to be as effective as an anti-depressant drug, and are within the recommended dose rates for Xtend-Life’s Marine Magnesium.

    Does Magnesium create loose bowel movements?

    Some forms of magnesium can cause those problems. Unlikely to experience that problem with the marine magnesium. If so, reduce to a half dose and then build up to the full dose.

    What age can you take Magnesium?

    From any age. Children from 9 - 18 years should take one cap a day. Children 4 - 8 years half a capsule.

    Should I take it at night or morning?

    For best results take after an evening meal.

    I take my Magnesium at night but at the same time I take my prescription medication, is this a good idea?

    It is always a good idea to leave a gap of 2 – 3 hours between medications and supplements.

    Why have you started making a single supplement product?

    Because magnesium is bulky and to get an optimum dose it requires two capsules for most adults. Because it is inexpensive we have left it for customers to purchase at their local health food shop, but because of customer demand and the desirability to take it with CX8 and the difficulty of getting a quality Magnesium with Potassium we have started producing it.

    Will I overdose if I take Sleeping pills, knowing that magnesium helps you sleep?

    You should never take sleeping pills for longer than a week as they can end up giving the opposite result long term. Best to try and go off the sleeping pills and try the magnesium on its own.

    Are these vegan, vegetarian, gluten free?

    Yes, they are.

    If I take Magnesium will it cause kidney stones?

    No, quite the opposite. It will help prevent them.

    Can I take CX8 and Magnesium together?

    We do not recommend that you take CX8 and Marine Magnesium with Potassium at the same time. This is because Magnesium may affect the efficacy of the Vitamin K2 ingredient which is present in CX8. Take CX8 in the morning if possible, as this increases your energy and then take the Magnesium at bedtime as it helps with sleep.

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