How YOU can use magnesium to treat insomnia, heartburn and even high blood pressure: It's the most popular supplement of the moment and now we reveal the best way to take it

It's fast become the trendiest new supplement on the market, with millions of social media clips claiming body-wide benefits - from sleep to memory and even muscle strength. Holland and Barrett recently named magnesium as their most popular supplement of 2025, with 45 million capsules sold. Meanwhile, the global magnesium market is set to nearly double over the next decade.But what's all the fuss about? Magnesium is, indeed, one of the most important minerals for our health, research shows - involved in around 300 different crucial bodily functions. It plays a vital role across the body - from making sure our cells, organs and brain are functioning properly, to maintaining muscles, nervous system and immune system and even stabilising mood.One large-scale study published last year by researchers in Australia even suggests that supplementing magnesium can reduce blood pressure. The problem is that, as the body can't produce it, we're reliant on food sources that don't typically feature daily in the British diet; nuts, seeds, fish such as mackerel, dark leafy greens.This means that nearly 60 per cent of Britons don't consume enough of it, according to studies. So, should we all be taking a supplement? And, if so, which kind? Here, experts reveal all on the mineral-of-the-moment. Sixty percent of Britons are magnesium-deficient and most are not aware, research showsWho should be taking magnesium - and how much is too much?Official estimates show that the majority of Britons are not consuming as much magnesium as they need. The NHS recommends women aged between 19 and 64 years old consume around 270mg of magnesium a day, while men of the same age are recommended to get around 300mg. Around 100g of several magnesium-dense foods contain 270mg. These include almonds, cashew nuts and pumpkin seeds, amongst others.Dark, leafy green vegetables - such as kale and spinach - also contain high levels of magnesium, as well as oats and most legumes.Most excitingly, just two squares of dark chocolate - ideally, 85 per cent cacao and higher - contains an impressive 100mg of magnesium. You can also up your intake of the mineral through magnesium supplements, sold on supermarket shelves as 375mg tablets, costing as little as 10p per dose. But experts say not everyone needs to supplement. 'If you're already eating a high magnesium diet or are on a medication that interacts with the mineral, then it may not be recommended,' says senior nutritionist at Holland and Barrett, Alex Glover. 'But it can be quite difficult, from a nutritional perspective, to get that level of magnesium every day. So supplementation can be helpful.' The NHS recommends limiting magnesium to 400mg a day due to the risk of diarrhoea and, at high doses, blood pressure and heart rhythm problems. Adds sleep and neurology specialist Dr Hanul Bhandari: 'Magnesium supplements are highly effective for fixing a deficiency and relieving its symptoms, but taking extra magnesium if your levels are already normal won't offer any extra health benefits.'Anyone with heart block or the autoimmune condition myasthenia gravis should consult a clinician before taking magnesium supplements, as should those with kidney disease. 'But for most healthy individuals, the body will naturally remove excess magnesium absorbed from the diet.'What type should I buy?It can be daunting to choose a magnesium supplement from the laundry list of options - many of which are combined with other compounds, such as glycinate, citrate and L-threonate.The compound paired with magnesium can affect how readily it dissolves and how much is absorbed, as well as how the product is typically used, say experts.The first step, therefore, is to narrow down what you want to achieve with your magnesium supplement. Magnesium glycinate, also called magnesium bisglycinate, is commonly chosen by people hoping to sleep better.Glycinate plays a role in normal nerve and muscle function, which can quiet the body and make it easier to drift off.In a 2025 randomized, double-blind trial, 155 adults with poor sleep took either 250mg of elemental magnesium from bisglycinate or placebo daily for four weeks.The magnesium group reported a small but statistically significant improvement in sleep-related symptoms, with greater benefit among people whose diets were lower in magnesium at baseline. Another meta-analysis found that magnesium shortened the time it took older adults to fall asleep by about 17 minutes.Says nutritionist Dr Naomi Newman-Beinart: 'Magnesium helps regulate melatonin, the sleep hormone, and supports GABA, a calming neurotransmitter in the brain.'While it isn’t a sleeping pill, it can make it easier to unwind and fall asleep naturally.'Magnesium glycinate and magnesium taurate have also been shown to have impressive benefits for blood pressure and heart health, say experts. 'Magnesium is really important in regulating blood pressure,' says Mr Glover. 'It may be the effect that we have the highest level of evidence about.'The mineral helps reduce blood pressure, research shows, by helping blood vessel walls relax and widen. Magnesium glycinate, priced at £7.50 for a month's supply, is said to be beneficial for sleepClinical studies have shown that supplementing with magnesium pills can reduce blood pressure levels significantly - though the most pronounced effects were seen in people with existing high blood pressure or low magnesium levels. Magnesium citrate, meanwhile, can act as a laxative, as well as increasing the body's overall magnesium reserves.'When you take magnesium orally (as a pill or powder), it has to go through your digestive system before your body can use it,' said Dr Newman-Beinart.'Some forms, such as magnesium citrate, can occasionally cause digestive upset.'Magnesium L-threonate, meanwhile, is often more expensive and heavily marketed for cognition because it was specifically developed with brain health in mind.Research shows that magnesium holds vital importance for neurological health by calming overactive brain signals, protecting the blood-brain barrier and dampening the inflammation that drives cognitive decline.Some research has shown that a higher magnesium intake is associated with larger brain volume and a lower risk of cognitive impairment.In animal studies, magnesium L-threonate increased magnesium in the brain and affected synaptic plasticity, a process involved in learning and memory. Research in humans is more limited. But a 2026 trial of 100 adults ages 18 to 45 who took 2g of magnesium L-threonate daily, found that participants scored higher on several cognitive tests, including those evaluating working and episodic memory.Finally, says Dr Bhandari, some magnesium-containing antacids are designed for immediate, short-term relief of occasional heartburn. These supplements are usually mixed with compounds that neutralise excess acid - such as magnesium hydroxide, magnesium carbonate or magnesium trisilicate. When they reach the stomach, explains Dr Bhandari, they rapidly lower acidity, soothing heartburn or indigestion as well as relaxing muscles in the gastrointestinal tract. Also known as milk of magnesia, magnesium hydroxide is found in a number of popular laxative medications, including Dulcolax.When should I take it - and what about the creams and salts?Dr Newman-Beinart says the supplement can be taken at any time of day.'However, because of its calming effect on the nervous system, many people find it particularly helpful to take it in the evening, when it may support relaxation and prepare the body for sleep,' she adds. Magnesium can also be used to lessen the symptoms of restless legs syndrome, which is when the lower limbs become unbearably twitchy and tingly at night time.For this, many people turn to magnesium creams, bath salts and sprays, because they are well absorbed and can help with muscle cramps.Magnesium citrate, meanwhile, is best taken with food, says nutritionist Alex Glover. Taking the supplement at mealtimes, he explains, helps prevent stomach upset, nausea and diarrhoea.READ MORE: The cheap as chips hair loss supplements that actually work