What is magnesium?

From the regulation of muscle contractions and blood pressure to energy production, blood sugar balance and even weight management and mood, magnesium’s role in the body is an important one. With such a long list of uses, it is no surprise it’s the fourth-most abundant mineral in the body, and involved in more than 300 enzymatic reactions.


The benefits of magnesium include:

  • Supports bone strength
  • May alleviate depression and reduce anxiety
  • Maintains cardiovascular health, including heart rhythm
  • May alleviate migraines and headaches
  • May improve sleep patterns
  • May improve pre-menstrual syndrome (PMS)
  • May regulate blood sugar
  • May boost metabolism and improve existing performance
  • Lowers inflammation
  • Supports the transportation of electrolytes including calcium and potassium

Discover our full range of health benefit guides including the best magnesium foods.

What forms of magnesium is best?

Foods that contain magnesium in small piles and on spoons and the chemical symbol for magnesium

Found naturally in rocks and seawater, there are a number of forms of magnesium, including carbonate, chloride, hydroxide, oxide and sulfate, as well as glycinate, lactate, malate, citrate and orotate.

Magnesium is available in various forms – each varying with regards its bioavailability and best use. For example, forms that dissolve well in water tend to be more easily absorbed in the gut. This means magnesium in the form of citrate, lactate and chloride are more completely absorbed than the oxide equivalent. Magnesium glycinate which is well-tolerated and effective for treating low magnesium levels, may be useful for anxiety, insomnia and stress conditions.

Top 10 benefits of magnesium

1. May strengthen bones and protect against osteoporosis

A number of population studies have reported positive associations between magnesium intake and bone mineral density in both men and women. This is because magnesium is involved in bone formation, as well optimising our use of vitamin D. Adequate magnesium may also play a part in keeping our muscles strong and healthy - this is an important strategy for preventing falls and fractures in the older population.

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2. May help with depression and anxiety

Happy woman

Magnesium has been shown to have a mood-improving effect with benefits achieved both with or without the use of antidepressant medication. This is especially relevant for people with mild mood symptoms as well as PMS-related or hypertensive anxiety. One reason for this may be because magnesium elevates levels of a neurotransmitter called GABA, which calms and alleviates anxiety.

Other research suggests a deficiency of magnesium may increase the body’s susceptibility to stress and as a result amplify our symptoms.

3. Maintains cardiovascular health

For those with hypertension, magnesium may help regulate blood pressure. There are also wider cardiovascular benefits, with higher magnesium intakes linked with a reduced risk of stroke.

4. May alleviate headaches/migraines

Magnesium deficiency appears to play a part in the development of migraines and headaches. However, evidence supporting the use of supplementation to prevent or reduce symptoms is, currently, limited.

5. May improve sleep

Woman asleep in bed

As we age, we experience changes in our sleep patterns. A study looking at the effect of magnesium on a group of 60- to 80-year-olds suggests the mineral may help reverse these changes. For the rest of us, magnesium may be a useful sleep aid, because it helps quieten the nervous system, creating a calm and relaxed disposition.

6. May alleviate pre-menstrual syndrome (PMS)

For many women of reproductive age, the strains of cyclical anxiety, stress, mood swings and bloating as well as menstrual migraine have a significant impact on their quality of life. Interesting studies suggest magnesium alone and in combination with vitamin B6 may help alleviate some of these symptoms.

7. May regulate blood sugar

Studies suggest that higher magnesium levels correspond to better insulin sensitivity and that supplementation can both improve insulin response and lower blood sugar.

8. May boost metabolism and improve exercise

Two women doing yoga

Magnesium is involved in energy production, oxygen uptake and electrolyte balance so it plays a key role in energy metabolism. Numerous studies suggest magnesium may improve exercise and athletic performance.

9. Lowers inflammation

Magnesium supplementation has been shown to significantly improve inflammatory markers including C-reactive protein (CRP) and nitric oxide levels.

10. Supports the transportation of electrolytes

As well as playing many other functional roles in the body, magnesium is essential for regulating levels of key electrolytes including sodium and potassium. Electrolytes are involved in regulating nerve and muscle function, hydrating the body and balancing blood acidity and pressure. Magnesium manages the movement of electrolytes across the cell membranes, via the ATP transport pump.

What about magnesium supplements?

If you’ve been advised to take a supplement, it’s important to select a high-quality product that supplies the form of magnesium that is most likely to benefit the condition you want to address. The product you choose may also be influenced by the dose you’ll need, and how many capsules you’re willing to take.

Common forms of magnesium that you’re likely to see on a supplement label include magnesium citrate, oxide, glycinate and malate.

Although magnesium supplements are well-tolerated by most people, some people experience symptoms such as nausea and diarrhoea. In order to minimise the risk of side effects, take the supplement with food and away from medication. High doses (more than 400mg) are more likely to cause digestive upset and currently there is insufficient evidence to support the effects of high doses over time.

Always keep to the directions on the label and refer to your GP or health professional if you are unsure.

Is magnesium safe for everyone?

Certain groups are more likely to be at risk of low levels these include older adults, type 2 diabetics and those with gut issues, such as Crohn’s disease. However, before you supplement you should be aware that certain medications may interact with magnesium or affect magnesium status so it is vital you seek the advice and guidance of your GP before supplementing.

Overall, is magnesium good for you?

If you're someone who struggles to sleep, suffers cramps, migraines and other symptoms of PMS or experience low mood then magnesium may be helpful. For more information, check out our magnesium-rich food guide, where you'll find why we need magnesium, along with plenty of magnesium-rich foods and recipes to incorporate into your diet.

Always speak to your GP or healthcare provider before taking a new supplement or if you are concerned about nutritional deficiencies.

This article was reviewed on 4 March 2024 by Kerry Torrens.

Kerry Torrens BSc. (Hons) PgCert MBANT is a registered nutritionist with a post graduate diploma in personalised nutrition & nutritional therapy. She is a member of the British Association for Nutrition and Lifestyle Medicine (BANT) and a member of the Guild of Food Writers. Over the last 15 years she has been a contributing author to a number of nutritional and cookery publications including Good Food.


All health content on goodfood.com is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. If you have any concerns about your general health, you should contact your local health care provider. See our website terms and conditions for more information.

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