A pharmaceutical expert has said there is little evidence to suggest that any one type of magnesium supplement has unique benefits over another, and has questioned whether supplements are even necessary for most people.
Writing on The Conversation website, Dipa Kamdar, Associate Professor in Pharmacy Practice at Kingston University, said there is no shortage of influencers listing the benefits of different types of magnesium supplements – from boosting brain function to easing anxiety and improving sleep.
Magnesium’s role and popularity
Magnesium is an essential mineral involved in hundreds of processes in the body. It helps muscles and nerves work properly, supports energy production and contributes to the maintenance of strong bones and teeth. It is also important for maintaining a healthy heart rhythm, regulating blood pressure and blood sugar levels.
There has been a surge in popularity of magnesium supplements on social media platforms like TikTok and Instagram, where influencers and wellness creators market the mineral as a “miracle cure-all”. The NHS recommends women aged between 19 and 64 get 270mg magnesium a day, and 300mg for men of the same age.
Different types of magnesium
Kamdar said magnesium glycinate, often promoted as the best option for sleep, combines magnesium with glycine, an amino acid that may improve sleep on its own. Research shows it is no more effective for sleep than other magnesium forms, but it is highly gentle on the stomach and easily absorbed.
Magnesium L-threonate is claimed to boost memory, focus, and brain function. Animal studies showed it increased brain magnesium levels, and a human study using 2g daily found improvements in working memory, reaction speed, and mental performance compared to a placebo. But human research is limited, and there is no proof it outperforms other forms for brain health.
Evidence and dietary advice
Magnesium malate combines magnesium with malic acid, a compound involved in energy production within cells. Correcting a deficiency improves muscle cramps and fatigue, and small studies in people with fibromyalgia showed reductions in pain and tiredness. However, Kamdar said there is a lack of strong evidence showing it works better than other well-absorbed forms for the general population.
Magnesium citrate and magnesium oxide are commonly used to treat constipation by drawing water into the bowel and to reduce the frequency and severity of migraines. Kamdar said both forms may reduce the severity and frequency of migraines and are cost-effective options, but the oxide form is absorbed less efficiently, so people may need higher doses to achieve the same effect as citrate, which may cause an upset stomach.
Kamdar said: “Overall, across a range of clinical trials, magnesium has shown some benefits for sleep quality, anxiety symptoms, migraines and blood pressure. But there’s no strong evidence that one form is better than another.” Most evidence came from small pilot studies, animal research or supplement marketing – rather than large, well-designed human trials.
She added: “While magnesium is beneficial for our health, it’s worth asking whether supplements are even necessary. For most people, a varied and balanced diet is the best way to get magnesium. Foods with naturally high levels of magnesium include leafy greens (such as spinach and kale), nuts and seeds, wholegrains and beans. These foods provide fibre, antioxidants and other nutrients that supplements cannot offer. They also reduce the risk of taking too much magnesium, which can cause diarrhoea or stomach upset.”
