Magnesium is involved in hundreds of processes throughout the body, from normal muscle and nerve function to energy production and bone health. Here is a straightforward guide to what magnesium does, how much Australian adults need and where supplements may fit.
Magnesium seems to be everywhere in wellness conversations.
It is added to powders, capsules, bath products and electrolyte blends. You may have heard it discussed in relation to muscles, sleep, stress, recovery or energy.
But before getting into the latest magnesium trend, there is a simpler question worth answering:
What does magnesium actually do?
Magnesium is an essential mineral, which means your body needs it but cannot make it on its own.
It plays a role in hundreds of enzyme systems and is involved in processes including energy production, normal muscle and nerve function, bone health and the regulation of blood glucose.
Most people can obtain magnesium through a varied diet containing foods such as nuts, seeds, legumes, wholegrains and leafy green vegetables.
Supplements can also have a place for some people but magnesium is not a cure-all, and taking more is not automatically better.
Here is what is worth knowing.
What is magnesium?
Magnesium is one of the major minerals found in the human body.
More than half of the body's magnesium is stored in bone, with much of the remainder found in muscles and other soft tissues. Only a very small amount circulates in the blood.
Magnesium acts as a cofactor, which means it helps enzymes carry out many of the chemical reactions your body needs to function.
That includes processes involved in:
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producing and using energy
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normal muscle function
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nerve signalling
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maintaining healthy bones
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glucose metabolism
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protein production
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moving calcium and potassium across cell membranes.
So while magnesium has become a popular wellness ingredient, its importance is not new.
Your body uses it every day.
1. Magnesium supports normal muscle function
Muscle movement depends on carefully controlled electrical and chemical signals.
Magnesium is involved in the movement of minerals such as calcium and potassium across cell membranes, which is important for normal muscle contraction and nerve signalling.
This is one reason magnesium is often discussed in relation to exercise and muscle function.
However, experiencing a muscle cramp does not automatically mean you are magnesium deficient.
Cramps can have many causes, including physical exertion, dehydration, certain medicines and some medical conditions.
If you regularly experience painful or unexplained muscle cramps, it is worth discussing them with a healthcare professional rather than assuming you simply need more magnesium.
2. Magnesium helps your nervous system function normally
Your nerves constantly send signals between your brain and the rest of your body.
Magnesium contributes to this process by helping regulate the movement of ions such as calcium and potassium across cell membranes, which supports normal nerve impulse transmission.
This is one of magnesium's established physiological roles.
It is also partly why magnesium often appears in conversations about relaxation and stress.
But there is an important distinction:
Magnesium is necessary for normal nervous-system function. That does not mean a magnesium supplement automatically treats stress or anxiety in everyone.
The evidence for supplemental magnesium in anxiety remains developing, with systematic reviews finding some encouraging results but limitations in study quality, population size, dose and formulation.
Good nutrition can support the normal functioning of the nervous system, but persistent anxiety or significant mental-health symptoms deserve appropriate professional care.
3. Magnesium is involved in energy production
When people hear the word energy, they often think of caffeine.
Your body, however, produces and uses energy through a much more complex series of biochemical processes.
Magnesium is involved in both aerobic and anaerobic energy generation and is required for reactions involving ATP, the molecule cells use as a major source of usable energy.
This does not mean taking magnesium provides an instant energy boost like a stimulant.
It means magnesium is one of the nutrients your cells require to carry out normal energy metabolism.
If you are feeling persistently tired, there can be many possible reasons including inadequate sleep, stress, iron deficiency, illness or other health conditions.
Magnesium should not be treated as the automatic solution to unexplained fatigue.
4. Magnesium contributes to healthy bones
Calcium tends to get most of the attention when we talk about bone health.
But magnesium matters too.
A substantial proportion of the body's magnesium is stored in bone, and magnesium is involved in bone structure and the metabolism of other minerals, including calcium.
Bone health is influenced by many factors, including:
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overall nutrition
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calcium intake
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vitamin D
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physical activity
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hormones
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age
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smoking and alcohol intake
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certain medicines and health conditions.
So rather than looking for one “bone-health nutrient”, it is more useful to think about the whole picture.
5. Magnesium plays a role in blood glucose regulation
Magnesium is also involved in the regulation of blood glucose and in biochemical reactions connected with carbohydrate metabolism.
This is another example of why minerals should not be viewed only through the lens of supplements.
Magnesium is part of normal physiology.
It works alongside many other nutrients and biological systems rather than operating as an isolated wellness ingredient.
If you have diabetes or another condition affecting blood glucose, magnesium supplements should not be used as a substitute for your prescribed treatment or professional medical advice.
How much magnesium do Australian adults need?
Australian Nutrient Reference Values set different Recommended Dietary Intakes depending on age and sex.
Adult men
19-30 years: 400 mg per day
31 years and over: 420 mg per day
Adult women
19-30 years: 310 mg per day
31 years and over: 320 mg per day
Requirements increase during pregnancy, with an RDI of 350 mg per day for pregnant women aged 19-30 and 360 mg for those aged 31-50.
These figures refer to total magnesium intake, including magnesium naturally present in food.
They are not instructions to take that amount in supplement form.
That distinction is important.
Which foods are naturally high in magnesium?
Magnesium is widely distributed throughout the food supply, particularly in plant foods.
Good sources include:
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nuts
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seeds
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legumes
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leafy green vegetables
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wholegrains
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some dairy foods
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some fish.
Examples listed by Healthdirect include foods such as peanuts, wholegrain bread, avocado, milk and salmon, alongside magnesium-rich foods such as leafy greens, legumes, nuts, seeds and wholegrains.
Simple ways to include more magnesium-rich foods
You could:
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sprinkle seeds over oats or yoghurt
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snack on a small handful of nuts
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add lentils or chickpeas to salads
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choose wholegrain bread more often
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include leafy greens with lunch or dinner
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add beans to soups, curries or pasta dishes
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include avocado with a meal
You do not need to build every meal around magnesium.
A varied diet naturally spreads your intake across the day.
Can you become deficient in magnesium?
Yes, although magnesium deficiency is uncommon in otherwise healthy people.
Healthdirect notes that people may be at greater risk if they:
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have an inadequate magnesium intake
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are older
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have type 2 diabetes
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have digestive conditions such as Crohn's disease
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experience long-term vomiting or diarrhoea
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have kidney problems
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have alcohol dependence
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use certain medicines over a long period.
Possible symptoms of magnesium deficiency can include:
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fatigue or weakness
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reduced appetite
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nausea or vomiting
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muscle spasms or tremors.
Severe deficiency can affect normal heart rhythm and cause other serious complications.
The important part is that these symptoms are not specific to magnesium deficiency.
Fatigue, nausea or muscle symptoms can have many possible causes.
A magnesium deficiency can be investigated using blood or urine tests, so if you are concerned, speak with your doctor rather than attempting to diagnose yourself based on symptoms alone.
What are the different types of magnesium supplements?
This is where things can get confusing.
A supplement label might mention:
magnesium glycinate
magnesium citrate
magnesium chloride
magnesium oxide
or another magnesium compound.
These names describe the substance magnesium has been combined with.
Different magnesium compounds can differ in properties such as solubility and how well they are absorbed.
Research summarised by the US National Institutes of Health suggests that forms that dissolve more readily tend to be absorbed more completely. Magnesium citrate, chloride, lactate and aspartate have shown greater bioavailability than magnesium oxide and magnesium sulfate in some studies.
However, that does not mean there is one universally “best magnesium” for everyone.
The appropriate product can depend on:
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why you are considering it
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the amount of elemental magnesium provided
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your diet
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how well you tolerate it
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your medications
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your health conditions.
A doctor or pharmacist can help if you are unsure.
What is magnesium glycinate?
Magnesium glycinate, sometimes called magnesium bisglycinate is magnesium bound to the amino acid glycine.
It has become particularly popular in wellness products and is often marketed around relaxation and sleep.
It is worth separating that popularity from what the research actually shows.
There is biological plausibility for magnesium being involved in processes related to the nervous system and sleep, but clinical research into magnesium supplementation for sleep remains mixed.
A systematic review of adult sleep research found that observational studies suggested an association between magnesium status and sleep quality, while randomised clinical trials produced inconsistent results.
A more recent 2024 review also found encouraging results in some studies of magnesium supplementation and sleep or anxiety, but concluded that larger, better-designed trials are still needed and that studies differed considerably in magnesium formulation and dosage.
So a responsible way to think about magnesium glycinate is:
It is a form of supplemental magnesium not a guaranteed sleep treatment.
Does magnesium help you sleep?
This is probably one of the most searched questions about magnesium today.
The answer is:
Possibly for some people, but the evidence is not strong enough to say magnesium is a proven sleep treatment for everyone.
Magnesium has established roles in normal nerve and muscle function, but studies specifically testing magnesium supplements for sleep have produced mixed results.
The 2023 systematic review of magnesium and sleep found uncertain results from randomised trials, while the 2024 review found positive outcomes in several studies but highlighted small sample sizes and substantial differences between the studies.
That matters because poor sleep can have many causes, including:
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inconsistent sleep schedules
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stress
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caffeine
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alcohol
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pain
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menopause
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sleep apnoea
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medications
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other health conditions.
A supplement should not become a substitute for identifying the reason you are struggling to sleep.
Is more magnesium better?
No.
More is not automatically better with vitamins or minerals.
For healthy adults, Australian Nutrient Reference Values set an Upper Level of Intake of 350 mg per day for magnesium from non-food sources such as supplements. This upper level does not apply to magnesium naturally present in food.
The upper level was established primarily because higher amounts of supplemental magnesium can cause diarrhoea.
Healthdirect also lists nausea and stomach cramps among possible effects of excessive magnesium supplementation.
This is why it is important to look at the amount of elemental magnesium provided by a supplement and follow appropriate directions rather than assuming a larger dose will deliver a larger benefit.
Can magnesium interact with medicines?
Yes.
Magnesium supplements can affect the absorption of some medicines, including certain antibiotics and medicines used for osteoporosis.
Some medicines, including certain diuretics and long-term medicines for acid reflux, can also influence magnesium levels in the body.
Speak with your doctor or pharmacist before using a magnesium supplement if you:
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regularly take prescription medicines
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have kidney problems
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have a diagnosed medical condition
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are pregnant or breastfeeding
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are taking several supplements
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have been advised to follow a medically restricted diet.
A quick conversation with your pharmacist can also help identify potential interactions.
Food first, supplements when appropriate
For most people, nutritious food is a sensible place to begin.
Foods containing magnesium also provide other useful nutrients such as fibre, protein, healthy fats, vitamins and minerals.
And because magnesium is found across many everyday foods, you do not necessarily need a highly specialised diet to include it.
Supplements can have a role when there is a specific nutritional need, an identified deficiency or when they have been recommended as appropriate for your circumstances.
At Swan & Mantis, we prefer to think of supplementation as something that complements everyday wellbeing habits, rather than replacing them.
If magnesium is something you are exploring as part of your routine, you can learn more about our magnesium products and check the individual product information before deciding what is appropriate for you.
A simple magnesium check-in
Before reaching for another supplement, consider:
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Do I regularly eat nuts or seeds?
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Do I include legumes?
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Do I choose wholegrain foods?
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Am I eating leafy green vegetables?
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Why am I considering magnesium?
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Am I trying to self-treat an unexplained symptom?
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Am I already getting magnesium through another supplement or electrolyte product?
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Do I take medicines that could interact with magnesium?
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Have I spoken with a healthcare professional if I am concerned about deficiency?
Sometimes the most useful first step is adding more variety to your meals.
Other times, it is asking a professional whether supplementation makes sense for you.
The takeaway
Magnesium deserves its place in the wellness conversation just perhaps not for all the reasons social media suggests.
It is an essential mineral involved in normal muscle and nerve function, energy metabolism, bone health and blood glucose regulation.
You can find it naturally in foods including nuts, seeds, legumes, leafy greens and wholegrains.
And while magnesium supplements including magnesium glycinate can form part of some people's routines, they are not a shortcut around good nutrition, sleep or appropriate medical care.
Instead of asking:
“What can magnesium fix?”
A better question might be:
“Am I getting enough magnesium as part of an overall nourishing diet?”
Because when it comes to everyday wellbeing, understanding what your body needs is generally more useful than chasing the latest wellness promise.
Frequently Asked Questions
What does magnesium do for the body?
Magnesium is an essential mineral involved in hundreds of biochemical processes. It contributes to normal muscle and nerve function, energy production, bone health, glucose regulation and the movement of minerals such as calcium and potassium across cell membranes.
How much magnesium do I need each day?
Australian adults generally need between 310 mg and 420 mg of magnesium per day, depending on age and sex. Women aged 19-30 have an RDI of 310 mg, increasing to 320 mg from age 31. Men aged 19-30 have an RDI of 400 mg, increasing to 420 mg from age 31.
What foods contain the most magnesium?
Magnesium-rich foods include nuts, seeds, legumes, leafy green vegetables and wholegrains. Milk, some fish, avocado and other foods also provide smaller amounts.
What is magnesium glycinate?
Magnesium glycinate is a supplemental form of magnesium in which magnesium is bound to the amino acid glycine. It has become popular in products marketed for relaxation and sleep, although current evidence does not establish magnesium glycinate as a guaranteed treatment for insomnia or anxiety.
Is magnesium glycinate better than magnesium citrate?
There is no single form of magnesium that is best for everyone. Different forms vary in solubility, absorption and tolerance. Evidence suggests some soluble forms, including citrate and chloride, are absorbed more readily than magnesium oxide, but your choice should also consider dose, purpose, medicines and individual tolerance.
Does magnesium help with sleep?
Research into magnesium supplements and sleep is promising in some areas but remains inconsistent. Some studies report improvements, while others do not, and researchers have called for larger and better-controlled trials. Magnesium should not be treated as a proven treatment for ongoing sleep problems.
What are the signs of magnesium deficiency?
Possible symptoms include fatigue, weakness, reduced appetite, nausea, vomiting and muscle spasms or tremors. These symptoms can have many other causes, so deficiency should not be diagnosed based on symptoms alone. A doctor can arrange appropriate testing.
Can you take too much magnesium?
Yes. Excessive magnesium from supplements can cause diarrhoea, nausea and stomach cramps. Australia's Nutrient Reference Values set an adult upper level of 350 mg per day from supplemental or other non-food sources. This limit does not apply to magnesium naturally present in food.