What are the benefits of magnesium and can it help you sleep?

Two experts weigh in on the benefits of magnesium for the body and why you should get more of it

A bunch of fresh bananas on yellow and blue background to symbolise the benefits of magnesium and one of the foods rich in the mineral
(Image credit: Getty Images)

Not many people know about the benefits of magnesium, despite the surge in love for the supplement over the last few years. It's not just a fantastic natural sleep aid, magnesium helps with so many of the body's essential processes.

The human body contains around 25g of this mineral, of which over half is stored in the skeletal system and the rest in our muscles, soft tissues, and bodily fluids. Without it, our bones, muscles, and joints would suffer and more than 300 different enzyme reactions would fail. 

Much like many of the other essential nutrients though, we don't make it ourselves. All the magnesium we need comes from the food we eat, any sleep supplements we take, and the environment around us. So getting enough, and from the right sources, requires some effort.

What are the benefits of magnesium? 

Magnesium is found in every cell in the body and it's vital for everyday functions because it's a cofactor, otherwise known as a helper molecule, explains Harley Street nutritionist Kim Pearson (opens in new tab). "It's involved in over 600 different chemical reactions in your body," she says. 

This includes the creation of energy from food, protein formation, and maintenance of our genes through DNA creation and repair. It also helps our muscles physically contract and relax, and it helps to maintain our nervous system by regulating neurotransmitters, extensive research from Radboud University (opens in new tab) says. 

"Yet 50% of us aren't getting enough, according to the National Institutes of Health (opens in new tab)," Pearson says. 

These are just some of the benefits of magnesium so many of us are missing out on: 

1. Strengthening bones and muscles

We often talk about the benefits of strength training when it comes to improving our muscle density and reducing the chance of conditions like osteoporosis, but magnesium plays a vital role in the maintenance of healthy bones, muscles, and joints too. 

One recent review by Wageningen University (opens in new tab) of 12 studies on magnesium found a strong link between higher intake of the mineral and increased bone density, especially in the hip and femoral neck, two areas that are particularly prone to fracture. While other studies by the University of Pavia (opens in new tab) in Italy have directly associated lower levels of magnesium with a higher risk of osteoporosis in adults. 

Woman holding cup of green juice post-workout, experiencing the benefits of magnesium

(Image credit: Getty Images)

2. Improve your athletic performance

As magnesium plays such an essential role in the maintenance of healthy bones, muscles, and joints, it's hardly surprising that having enough of it in the body will impact how it functions in daily life - and in sport. 

"Some studies, including one by Indiana University (opens in new tab), has shown that magnesium can boost our athletic performance in sports such as running, Nordic walking, swimming, and cycling. So, if you manage to boost your magnesium levels to a healthy amount, you may see an improvement in your activity levels," Pearson says. 

3. Reduce stress levels

If you're looking for alternative ways to deal with stress, a long soak in a magnesium-rich bath could certainly help. "Magnesium can help with brain function and reduce stress by positively impacting the hypothalamus," Pearson says, "This part of the brain controls our stress response."

For the same reasons, magnesium can help to lower anxiety levels and decrease our risk of depression. A higher intake of magnesium is naturally not a replacement for adequate mental health aid, however, research by the University of Vermon (opens in new tab)t found that taking 248mg of magnesium every day significantly reduced symptoms of anxiety in subjects.

For those struggling with menopause and anxiety, this could be a way to lessen the symptoms, as a study by Tehran University of Medical Sciences (opens in new tab) also found a strong connection between supplementing magnesium and a lower risk of depression and anxiety. 

Plate of fish, which is high in magnesium, on light blue background

(Image credit: Getty Images )

4. It may reduce the risk of heart attacks and strokes

A diet of magnesium-rich foods could be a way to lower the risk of a heart attack or stroke in the future, explains Pearson. "By helping to quell inflammation, regulate blood clotting, and combat oxidative stress, a magnesium-rich diet containing nuts, whole grains, cereals, leafy green vegetables, berries, bananas, fish, and seafood, could lower the risk of heart disease or a stroke," she says. 

And there's plenty of evidence to suggest that this is the case. A study by Indiana University (opens in new tab) shows magnesium supplements can help lower high blood pressure levels - a serious risk factor for heart disease. While a review by University Hospital of Sant Joan de Reus (opens in new tab) links diets high in magnesium with a lower risk for heart disease, stroke, and high blood pressure. 

4. It may reduce the risk of diabetes

Eating plenty of magnesium-rich whole grains, beans, nuts, and green leafy vegetables may also reduce your chance of type 2 diabetes. 

"Magnesium can help to restore insulin function and lower blood glucose levels in people with insulin resistance," explains Pearson, pointing to a study by Mashhad University of Medical Sciences (opens in new tab). "This can lead to type 2 diabetes, as well as being a culprit for midlife food cravings, menopausal weight gain, food cravings, and mood swings."

5. Reduce the frequency of migraines

While migraine cures are often few and far between, research suggests that magnesium could be the go-to mineral for anyone experiencing these nasty headaches. 

According to research by Tabriz University of Medical Sciences (opens in new tab), one of the main roles of the mineral in the neurological system is to conserve neurons' electrical potential. When someone is deficient in magnesium, the study found, they are more likely to experience neurological complications - including migraines. 

Further studies also support the idea that magnesium supplements can prevent and even treat migraine headaches when they occur. A review of 21 studies by Taipei Medical University (opens in new tab) found that oral magnesium supplements were significantly beneficial in reducing the intensity and frequency of migraines, but intravenous magnesium worked even better and reduced symptoms within just 15 minutes. 

Glass bowl of cashews on bright yellow background

(Image credit: Getty Images)

Which foods contain magnesium? 

Some foods, such as dark chocolate, are surprisingly high in magnesium. It's one of the reasons why it's often called healthy chocolate as per 28g of good quality, high percentage dark chocolate, there's around 62mg of magnesium.

These are other foods high in magnesium:

  • Avocados
  • Seeds, especially pumpkin and chia 
  • Nuts, particularly almonds, cashews, and peanut butter 
  • Legumes 
  • Whole grains, such as brown rice and wholegrain pasta 
  • Tofu
  • Fish like salmon and halibut 
  • Seeds
  • Bananas 
  • Leafy greens 

Does magnesium help you sleep? 

Yes, magnesium's ability to help us sleep better is one of the mineral's biggest perks. "Research from Tehran University of Medical Sciences (opens in new tab) shows that adding magnesium to your diet can improve your overall sleep quality, especially for those who already suffer from disrupted patterns," explains Lola Biggs, sleep specialist and registered dietician at Together Health (opens in new tab)

It's so effective and one of the best sleep aids, she says, because "magnesium helps to support the deep restorative phase of sleep by maintaining healthy levels of GABA, a neurotransmitter which promotes sleep."

Magnesium for sleep is also widely researched, making it one of the safer supplements to add to your diet. For example, another review of three studies from Dalhousie University (opens in new tab) involving older adults found that supplementing magnesium in 320 - 370mg doses every day for two months decreased the time it took participants to fall asleep, and increased their total time spent asleep compared with a placebo.

Which magnesium supplement is best? 

There's no one magnesium supplement that is better than another, as everyone will have different needs depending on how much magnesium they get from their diet. In general, women need 310 to 320 mg of magnesium per day, Pearson says, but some people will need more. 

"But restricting food to lose weight, being on a vegetarian diet, or eating too many processed foods, which strip out magnesium, can all lead to a deficiency," she explains. This is where a supplement may come in useful. 

Grace Walsh
Health Editor

A digital health journalist with over five years experience writing and editing for UK publications, Grace has covered the world of health and wellbeing extensively for Cosmopolitan, The i Paper and more.


She started her career writing about the complexities of sex and relationships, before combining personal hobbies with professional and writing about fitness. Everything from the best protein powder to sleep technology, the latest health trend to nutrition essentials, Grace has a huge spectrum of interests in the wellness sphere. Having reported on the coronavirus pandemic since the very first swab, she now also counts public health among them.