Magnesium and your health
Key facts
- Magnesium is needed for healthy muscles, nerves, bones and blood sugar.
- Symptoms of low magnesium are headaches, nausea, fatigue and loss of appetite.
- Leafy greens, legumes, nuts, seeds and wholegrains are high in magnesium.
- How much magnesium you need depends on your age, sex and stage of life.
- Getting enough magnesium decreases your chances of health problems.
What is magnesium?
Magnesium (Mg) is a mineral that is essential for healthy muscles, nerves, bones and blood sugar levels. Not getting enough magnesium in your diet can increase the chance of health problems such as:
Why is magnesium important for my health?
Magnesium is needed for many processes in your body.
Magnesium is important:
- for your muscles and nerves to work properly
- to keep your blood sugar and blood pressure at the right level
- to make proteins, bone and DNA (genetic material)
Where does magnesium come from?
You can get magnesium from food or from a supplement. Foods high in magnesium are:
- green leafy vegetables
- legumes
- nuts and seeds
- wholegrains
How much magnesium do I need?
How much magnesium you need depends on your age, sex and life stage.
See the table for magnesium requirements across your lifespan.
| Stage of Life | Recommended dietary intake* of magnesium (milligrams per day) |
|---|---|
| 0-6 months | 30 |
| 7-12 months | 75 |
| 1-3 years | 80 |
| 4-8 years | 130 |
| 9-13 years | 240 |
| 14-18 years males | 410 |
| 14-18 years females | 360 |
| 19-30 years males | 400 |
| 19-30 years females | 310 |
| 31-70+ years males | 420 |
| 31-70+ years females | 320 |
| During pregnancy | 350 to 400, depending on age |
| While breastfeeding | 310 to 360, depending on age |
*Recommended dietary intake (RDI): is the average daily dietary intake level that is needed to meet the nutrient requirements of nearly all (97–98%) healthy people in a certain life stage and gender group.
Can I have too little magnesium?
Yes. Low magnesium levels can be caused by poor diet or some health conditions.
Taking some medicines for a long time can lead to low magnesium levels, such as:
- medicines for diabetes
- antibiotics and antiviral medicines
- diuretic medicines
- chemotherapy (used to treat cancer)
- immunosuppressants (medicines that suppress your immune system)
- protein-pump inhibitors (used for reflux)
Over time, low magnesium levels can cause problems with the flow of nutrients in and out of your cells. This includes the flow of calcium and potassium.
If you don't have enough magnesium in your body, you might have symptoms such as:
- headaches
- loss of appetite
- nausea and vomiting
- fatigue and weakness
Severe magnesium deficiency can cause:
- numbness or tingling
- muscle cramps
- seizures
- an abnormal heart rhythm
People with magnesium deficiency have a greater chance of developing:
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Can I have too much magnesium?
You can't get too much magnesium from food because your kidneys will clear out extra magnesium through your urine (pee).
Normally, magnesium poisoning or toxicity happens when too much magnesium is taken in the form of:
- magnesium supplements
- antacids
- laxatives
Magnesium poisoning or toxicity is rare.
You should not take supplements with more than the recommended amount of magnesium, as this can cause:
Too much magnesium can lead to an irregular heartbeat or cardiac arrest.
Speak with your doctor if you’re worried about your magnesium levels. Your doctor may test your levels with a magnesium blood test.
Read more about foods high in magnesium and when you may need to take supplements.
Some Magnesium supplements contain vitamin B6, which may be listed on the label as pyridoxine hydrochloride, pyridoxal 5-phosphate or pyridoxal 5-phosphate monohydrate. Stop taking these supplements if you experience symptoms of peripheral neuropathy, such as tingling, burning or numbness. See your doctor as soon as possible.
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Resources and support
Nutrition Australia has information about how to keep you and your family healthy through diet.
See Eat for Health for more information about magnesium and your health.
You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: April 2025
