Short answer: Magnesium is an essential mineral your body uses in more than 300 different processes, from helping your muscles contract and relax, to supporting your nervous system, turning food into energy, keeping bones strong, and playing a role in sleep, mood and a steady heartbeat. It's a genuine multitasker, and because many people don't get enough from diet alone, it's one of the most worthwhile minerals to pay attention to.
Here's the full picture of what magnesium does, and why it matters.
Why magnesium matters so much
Magnesium is the fourth most abundant mineral in your body, stored mostly in your bones and muscles. It acts as a helper for over 300 enzyme systems, which is a fancy way of saying it's quietly involved in an enormous amount of what keeps you running day to day. The catch? Surveys suggest a large share of adults don't get enough magnesium from food alone, which is exactly why it's such a popular mineral to top up.
Below are the main jobs magnesium does in the body.
1. Muscle function
This is one of magnesium's headline roles. It helps your muscles both contract and relax, working in partnership with calcium. That relaxation side is why magnesium is so often associated with easing muscle tension and occasional cramps, and why active people pay attention to it. Muscles draw on more magnesium during exercise, and it supports recovery afterwards.
Read more: Does magnesium help with muscle cramps?
2. Sleep and relaxation
Magnesium is probably best known lately as a "wind-down" mineral, and there's a logic to it. Magnesium helps regulate the calming neurotransmitters (like GABA) that quiet a busy mind, and it plays a role in producing melatonin, the hormone that signals your body it's time to sleep. People whose racing thoughts keep them awake, or whose sleep is broken by leg cramps, are often the ones who notice it most.
Read more: Does magnesium help you sleep?
3. Stress and mood
Magnesium supports normal nervous system and psychological function, and it's involved in making serotonin, a key mood neurotransmitter. There's a two-way street here worth knowing: stress can deplete your magnesium, and low magnesium can make stress feel harder to handle. For persistent low mood or anxiety, it's important to see a health professional, but keeping magnesium topped up supports the system as a whole.
Read more: Does magnesium help with stress and anxiety?
4. Energy and fighting tiredness
Feeling constantly run-down? Magnesium is essential for energy metabolism, the process of converting the food you eat into usable energy, and it contributes to the reduction of tiredness and fatigue. It won't replace good sleep and nutrition, but it's a foundational piece of feeling energised.
5. Headaches and migraines
This is an area of real research interest. People who experience migraines tend to have lower magnesium levels, and magnesium is one of the better-studied nutrients in migraine prevention. The exact role is still being explored, so if you get frequent migraines, the right move is to work with your doctor on a plan, but the magnesium connection is a genuine one.
Read more: Does magnesium help with headaches and migraines?
6. Heart and blood pressure
Your heart is a muscle, and like all muscles it relies on magnesium to contract and relax properly and to keep a steady rhythm. Adequate magnesium intake is also associated with healthy blood pressure. As always, anything heart-related should be guided by your health professional, but magnesium is part of the supporting cast.
7. Strong bones
Around half to two-thirds of your body's magnesium lives in your bones. It works alongside calcium and vitamin D in building and maintaining healthy bone structure, a quieter, long-term benefit that's easy to overlook.
Are you getting enough?
Quite possibly not. In Australia, the recommended daily intake of magnesium is roughly 310–320mg for women and 400–420mg for men, rising a little with age, yet a large proportion of adults fall short. You're more likely to run low if you eat a limited diet, are very physically active, are under sustained stress, or have certain digestive conditions.
Signs that can be associated with low magnesium include muscle cramps, fatigue, poor sleep and feeling on edge, though these overlap with lots of other things, so they're a prompt to look at your intake rather than a diagnosis.
Magnesium-rich foods
The best place to start is your plate. Magnesium-rich foods include:
- Leafy greens, like spinach, silverbeet and kale
- Nuts and seeds, like almonds, cashews and pumpkin seeds
- Legumes, like black beans, chickpeas and edamame
- Whole grains, like brown rice, oats and wholemeal bread
- Dark chocolate (the good news you were hoping for)
- Avocado and banana
A varied diet built around these is the foundation. A supplement is simply an easy way to top up the gap if you're falling short.
A quick word on forms of magnesium
Not all magnesium supplements are the same. The "form" affects how well it's absorbed and how it's typically used:
- Magnesium citrate, well absorbed and a great all-rounder. (It's the form in our gummies.)
- Magnesium glycinate, gentle on the stomach and often favoured for relaxation and sleep.
- Magnesium oxide, the most studied form in migraine research, though less readily absorbed.
For a daily top-up across all the roles above, a well-absorbed form like citrate is a sensible, versatile choice.
How to get the most from magnesium
- Be consistent. Magnesium works best as a steady daily habit.
- Pair food and supplement. Build meals around magnesium-rich foods and use a supplement to fill the gap.
- Time it to your goal. Many people take it in the evening to support wind-down, but any consistent time works.
- Mind your kidneys and medications. Magnesium is generally safe for people with healthy kidneys, but very high doses can cause a laxative effect. If you have kidney issues, are pregnant or breastfeeding, or take medication, check with your health professional first.
Our Haircarebear Magnesium Gummies make the daily habit easy, 150mg of well-absorbed magnesium citrate per serve in a berry-flavoured gummy, and they're pectin-based, so vegan- and vegetarian-friendly.
The bottom line
Magnesium is a true multitasker, supporting your muscles, nervous system, energy, sleep, mood, heart and bones, all from one humble mineral. Because so many of us fall short of what we need, keeping magnesium topped up through a good diet (and a supplement when helpful) is one of the simpler, higher-value things you can do for your everyday wellbeing.
Frequently asked questions
What does magnesium do for the body? Magnesium supports more than 300 processes, including muscle and nerve function, energy production, sleep and relaxation, mood, a steady heartbeat and strong bones. It's one of the most wide-reaching minerals there is.
What are the signs of low magnesium? Possible signs include muscle cramps, fatigue, disrupted sleep and feeling on edge, though these overlap with many other causes, so treat them as a reason to review your intake rather than a diagnosis.
When's the best time to take magnesium? Any consistent time works. Many people take it in the evening because of its calming, wind-down association, but the most important thing is taking it regularly.
Can I get enough magnesium from food? You can get a lot from leafy greens, nuts, seeds, legumes, whole grains and dark chocolate, but many adults still fall short, which is where a supplement helps top up the gap.
Which form of magnesium is best? It depends on your goal: citrate is a well-absorbed all-rounder, glycinate is gentle and popular for relaxation, and oxide is most studied for migraine. For a daily top-up, citrate is a versatile choice.
Written by the Haircarebear team. Reviewed by Katie van der Mye, Innovations Manager (BA, MPRA, MM).
This article is general information only and isn't medical advice. Please speak with your health professional about your individual needs.
Sources: overviews of magnesium's role in health from UCLA Health, Mayo Clinic Press and WebMD, and research on magnesium for sleep and migraine; Australian recommended intakes from the NHMRC Nutrient Reference Values.