Marine Magnesium with Potassium

54 reviews
An excellent source of natural bio-available 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
    $12.95 USD
    30 Day Supply | Size: 60 Capsules

    Free DHL Express Courier on orders over $125 (USA only). Find country specific shipping details here

    Features & Benefits

    What is Marine Magnesium with Potassium?

    Marine Magnesium with Potassium is a new product developed to meet the needs of our customers with a specific emphasis on cardiovascular health. Magnesium can help with:

    • Heart health
    • Blood sugar levels
    • Brain health
    • Muscle contractions and cramps

    Magnesium is available in a variety of different forms in a multitude of products, 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.

    Called Aquamin MG®, the magnesium in our formulation 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.

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

    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.

    Do I Need Magnesium and Potassium?

    Absolutely! If you don't have optimum levels of magnesium in your body of which about half resides in your bones and the other half in soft tissue and organs with only about 1% in your blood you would be in a sorry state. This is because magnesium is an essential component of RNA (ribonucleic acid), which is responsible for making the proteins needed for our cells to function properly (It is estimated that 68% of Americans do not even reach the minimum recommended daily levels for magnesium in their diet).

    In addition, magnesium is needed for over 300 metabolic biochemical reactions in our body. These reactions help sustain normal nerve and muscle functions as well as helping support a healthy immune system – not to mention the important role it plays in helping normal blood pressure and heart rhythm.

    And these are only some of the well-established benefits of magnesium. There is ongoing research into the role of magnesium and how it may potentially help in the area of Type 2 diabetes, migraines, depression, and other chronic conditions. Low levels of magnesium have been associated with a number of these conditions.

    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 105mg of elemental Potassium in this formula.

    How Does it Work?

    The magnesium works in multiple ways. Below are just a few of the mechanisms of how magnesium can benefit your body:

    • For your heart health it works by helping your heart muscle cells to relax. It does this by countering calcium which stimulates contractions. Because these two minerals compete with each other the magnesium helps ensure the heart cells do not get overstimulated.
    • For your brain health it works by being the gatekeeper of the N-methyl-D-aspartate (NMDA) receptors. The magnesium sits inside these receptors preventing them from over stimulation which in turn can kill nerve cells and in turn may cause brain damage.
    • For muscle contractions.  Although there are mixed results from studies addressing the application of magnesium to relieve cramps there is evidence that it can be helpful with many people. Cramps occur when there is not enough magnesium to compete with calcium which binds with proteins such as troponin C and myosin which triggers off contractions.
    • For improved blood sugar control as 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.


    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).

    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.

    Customer Reviews
    4.8 Based on 54 Reviews
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    Filter Reviews:
      Tim H.
      Canada Canada

      magnesium relieves joint pain

      Within a very short time my knee and ankle pains were reduced and now there is virtually no pain.

      Paul D.
      United States United States

      Stops leg cramps

      When I miss taking this product before bed I will readily find myself waking up with leg cramps. The potency of the Magnesium is immediately noticeable. Knowing that magnesium is used in over 800 body functions makes me to want to have a high efficacy product. Xtend Life has proved to be an immediate winner.

      Charles G.
      United States United States

      Effective yet gentle

      I love this magnesium because it’s effective, yet gentle. I also love that it has many trace elements as well. The efficacy I’ve seen has been to help my heart maintain a normal rhythm and help me sleep. I had an irregular heart rhythm, Bigeminy, sometimes caused by low magnesium . My cardiologist measured my serum magnesium and it was normal. But over three quarters of the magnesium in my body is inside the cells and not measurable by conventional tests. So I started this magnesium and my heart rhythm is now normal. It also really helps me fall asleep. Please know these two things: 1. Everyone is different and it may affect others differently. 2. I believe my arrhythmia went away from the magnesium, but one anecdote is not proof; furthermore correlation doesn’t prove causation.

      Charles G.
      United States United States

      Excellent source of Magnesium

      This contains both Magnesium and Potassium. It’s very high purity and also very gentle on my stomach . This is an excellent time

      Doreen K.
      United States United States

      Great Product!

      best magnesium supplement I have tried

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