Can Vitamins and Minerals Really Calm Restless Legs Syndrome?

Restless leg syndrome has a strong genetic component, which is why we just published a restless leg syndrome report for Gene Food premium subscribers and have received several questions from users asking our take on whether magnesium is effective in alleviating the symptoms of this condition.

If you have experienced restless legs syndrome, which has an incidence of 5-10% globally and is much more common in pregnancy, you probably heard that magnesium and some other minerals can help relieve the symptoms.

But is this advice based on evidence?

Breaking down a meta-analysis

Marshall and colleagues [X] have asked themselves the same question and undertook a systematic review of all papers that mentioned “restless legs syndrome” (or its clinical synonyms) in combination with “magnesium”. This detected over 800 papers, but after reviewing them and excluding irrelevant studies or those for which they could not locate the main text, they ended up with just eight articles for an in-depth review. Strikingly, only one was a placebo-controlled trial, while the rest were case reports (essentially, scientific “just so” stories that cannot provide definitive proof). This immediately suggested that drawing clear conclusions from this analysis would be difficult.

The case for magnesium

The placebo-controlled trial that Marshall and coworkers reviewed [X] did not detect any significant benefits of magnesium supplementation for relieving restless legs symptoms. However, the devil is in the details (which the authors found notoriously difficult to find in the report): the dose of magnesium, as well as the limited cohort size used in the study, could have masked a more positive result. In contrast, the case reports suggested some benefits of supplementing magnesium for RLS, including in pregnancy [X] and diabetes [X].

Notably, the pregnancy study used high-dose intravenous magnesium supplementation. Since this systematic review was published, new data has emerged, including a study suggesting that magnesium deficiency may indeed be associated with restless legs symptoms in pregnancy [X]. 

Other vitamins and minerals

How about other minerals and vitamins? The same study in pregnant women mentioned above has suggested that reduced zinc levels also correlate with restless legs symptoms [X]. In addition, a recent placebo-controlled study showed that combining magnesium with vitamin B6 may be beneficial [X]. Finally, iron deficiency is known to be behind restless legs symptoms in some people [X].

When considering specific treatments for a condition, it is most reassuring when the mechanism of their action against this condition is well understood. Unfortunately, this isn’t quite the case for most supplements in the case of RLS. Mechanistically, this syndrome is typically linked with the neurotransmitters dopamine and GABA (gamma-aminobutyrate), and evidence from genetics, reflected in our Restless Legs score, confirms these observations. These neurotransmitters are like the ‘on’ and ‘off’ switches for neural circuits, respectively, including for those circuits that control limb movements. Some vitamins and minerals, including iron [X], magnesium [X] and vitamin B6 [X], have been implicated in keeping these circuits balanced. However, vitamins and minerals play a lot of different roles in our bodies, and more research is needed to understand whether (and if at all) they work in this particular way to relieve RLS symptoms. 

Bottom line

Overall, the jury is still out on the efficacy of supplements for relieving restless legs syndrome, particularly for people who are not pregnant. However, since many people happen to have reduced levels of magnesium and iron, and vitamin B6 also has various benefits, you can consider supplementing iron, magnesium and vitamin B6 if you suffer from RLS symptoms – ideally, in consultation with your doctor.