TODO: add alt text

Magnesium for sleep and anxiety: What you need to know

From the desk of Robb Wolf

<p><span style="font-weight: 400">Sleep and mood issues are rarely a simple fix. Even mild cases of insomnia, anxiety, and depression are multifactorial problems that require a holistic approach. I believe ensuring optimal magnesium levels should be part of that approach.</span></p><p><span style="font-weight: 400">I believe this because magnesium supports the chemical systems that underpin restful sleep and relaxation. If you’re deficient in magnesium, for instance, you’ll likely have problems synthesizing melatonin, the sleep hormone.</span></p><p><span style="font-weight: 400">A couple of small, well-designed </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3703169/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">studies</span></a><span style="font-weight: 400"> suggest that magnesium supplementation can improve sleep quality. I’ll dive into those later.</span></p><p><span style="font-weight: 400">There’s also considerable literature on magnesium for anxiety, the world’s most common mental health disorder. Anxiety and poor sleep, as you might imagine, are </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6700255/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">closely linked</span></a><span style="font-weight: 400">.</span></p><p><span style="font-weight: 400">Even if you don’t have clinical anxiety, all of us experience bouts of nervousness, fear, and apprehension from time to time.</span></p><p><span style="font-weight: 400">For myself, I don’t like having stuff on my plate. Not one bit. If it’s on my plate, I’m chomping down on it hard. So anxiety often creeps up in my email inbox. And when that anxiety leads to the mistake of checking my email close to bedtime, my sleep notices. That’s one reason I generally avoid my computer at night.</span></p><p><span style="font-weight: 400">I also make sure to get 400—600 mg magnesium per day through diet and supplements (magnesium malate) to support sleep, relaxation, and many other functions. It may even provide a buffer against the email inbox dilemma. I wrote this blog to explain how that works.</span></p><h2><strong>What Is Magnesium?</strong></h2><p><span style="font-weight: 400">Magnesium is a mineral that supports a vast array of physiological processes. For example, magnesium is an essential cofactor in the production of adenosine triphosphate (ATP), the energy currency that powers all living cells.</span></p><p><span style="font-weight: 400">Magnesium is technically an </span><a href="https://drinklmnt.com/blogs/health/what-are-electrolytes-and-why-are-they-important" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">electrolyte</span></a><span style="font-weight: 400">, but most of its functions are unrelated to electricity conduction. (Pure electrolyte functions are mostly carried out by sodium, chloride, potassium, and calcium).</span></p><p><span style="font-weight: 400">Some roles </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5926493/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">magnesium plays</span></a><span style="font-weight: 400"> include:</span></p><ul><li style="font-weight: 400"><span style="font-weight: 400">Structuring hard tissue like teeth and bones</span></li><li style="font-weight: 400"><span style="font-weight: 400">Synthesizing and repairing DNA</span></li><li style="font-weight: 400"><span style="font-weight: 400">Keeping calcium levels within healthy ranges</span></li><li style="font-weight: 400"><span style="font-weight: 400">Regulating muscle contraction, including heartbeat</span></li><li style="font-weight: 400"><span style="font-weight: 400">Supporting the production of glutathione, your body’s primary antioxidant</span></li><li style="font-weight: 400"><span style="font-weight: 400">Creating usable energy as ATP</span></li></ul><p><span style="font-weight: 400">When magnesium is depleted, a number of systems suffer. This makes sense, considering magnesium is required for over 300 enzymatic reactions in your body.</span></p><p><span style="font-weight: 400">Moderate magnesium deficiencies may result in fatigue, weakness, muscle cramps, high blood pressure, increased inflammation, kidney stones, and osteoporosis. More severe deficiencies can cause cardiac arrhythmia, heart palpitations, hypocalcemia (low calcium levels), hypokalemia (low potassium levels), and bad muscle spasms.</span></p><p><span style="font-weight: 400">Deficiencies can result from a diet low in plant foods, the use of antacid drugs, vomiting, diarrhea, and a variety of digestive disorders. We also lose magnesium through sweat, so athletes and sauna users will have elevated needs.</span></p><h2><strong>Why Magnesium Is Relaxing</strong></h2><p><span style="font-weight: 400">Magnesium is known as the relaxation mineral because it has a calming effect. This effect appears to be mediated by the neurotransmitters GABA and glutamate.</span></p><p><span style="font-weight: 400">Specifically, magnesium helps increase GABA (a calming neurotransmitter) and decrease glutamate (an excitatory neurotransmitter) in the brain. It does so by </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452159/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">blocking</span></a><span style="font-weight: 400"> the brain’s N-methyl-d-aspartate (NMDA) receptors, which are sensitive to glutamate.</span></p><p><span style="font-weight: 400">Through this mechanism, magnesium </span><a href="https://pubmed.ncbi.nlm.nih.gov/12163983/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">regulates</span></a><span style="font-weight: 400"> a variety of systems involved in sleep. These include the renin-angiotensin-aldosterone system, the HPA system, the GABAergic system, and the glutamatergic system.</span></p><p><span style="font-weight: 400">GABA and glutamate are also implicated in anxiety and depression. It’s a </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452159/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">complex picture</span></a><span style="font-weight: 400">, but the gist is that less glutamate and more GABA (borne of magnesium supplementation) can ameliorate these disorders.</span></p><p><span style="font-weight: 400">We’ll talk more about mood disorders soon. Let’s review the evidence on magnesium for sleep now.</span></p><h2><strong>Can Magnesium Improve Sleep?</strong></h2><p><span style="font-weight: 400">Contrary to popular belief, there isn’t a boatload of evidence on magnesium for better sleep. But the two studies that </span><i><span style="font-weight: 400">do</span></i><span style="font-weight: 400"> exist are promising.</span></p><h3><strong>Study #1: Magnesium for Insomnia</strong></h3><p><span style="font-weight: 400">In this </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3703169/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">double-blind placebo-controlled trial</span></a><span style="font-weight: 400">, researchers randomized 46 elderly patients with insomnia to receive either 500 mg magnesium or placebo daily for 8 weeks. Using some fancy statistical footwork, the researchers controlled for confounding factors like caffeine intake, dietary magnesium, and caloric intake. The idea was to isolate the effect of supplemental magnesium.</span></p><p><span style="font-weight: 400">At the end of the 8 weeks, the magnesium group showed improvements in:</span></p><ul><li style="font-weight: 400"><span style="font-weight: 400">Sleep time</span></li><li style="font-weight: 400"><span style="font-weight: 400">Sleep efficiency (time sleeping divided by time in bed)</span></li><li style="font-weight: 400"><span style="font-weight: 400">Sleep onset latency (how quickly one falls asleep)</span></li></ul><p><span style="font-weight: 400">There were also hormonal differences worth mentioning. Compared to the placebo group, the magnesium folks had:</span></p><ul><li style="font-weight: 400"><span style="font-weight: 400">Lower levels of cortisol (a stimulating hormone that you want to be suppressed at night)</span></li><li style="font-weight: 400"><span style="font-weight: 400">Higher levels of the sleep hormone, melatonin (Magnesium is required to synthesize serotonin, a melatonin precursor)</span></li><li style="font-weight: 400"><span style="font-weight: 400">Higher levels of renin, a hormone </span><a href="https://pubmed.ncbi.nlm.nih.gov/20110736/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">linked</span></a><span style="font-weight: 400"> to restful sleep and nighttime release of growth hormone</span></li></ul><p><span style="font-weight: 400">All positive things for the magnesium group.</span></p><h3><strong>Study #2: Magnesium for Slow Wave Sleep</strong></h3><p><span style="font-weight: 400">This </span><a href="https://pubmed.ncbi.nlm.nih.gov/12163983/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">study</span></a><span style="font-weight: 400"> employed a crossover design. Six elderly people took magnesium for 20 days, “washed out” for 2 weeks, then took a placebo for the next 20 days. Six others did the same but in reverse order.</span></p><p><span style="font-weight: 400">The researchers hypothesized that taking magnesium might reverse the decline in slow-wave sleep (deep sleep) seen with aging. This sleep stage is crucial for hormone production and tissue regeneration, so we want to get more of it.</span></p><p><span style="font-weight: 400">Well, magnesium supplementation did increase slow-wave sleep by about 60%. It also decreased cortisol and increased renin. Promising stuff.</span></p><h2><strong>Magnesium for Anxiety and Depression</strong></h2><p><span style="font-weight: 400">Anxiety and depression are the two most common mental health disorders. Anxiety tops the list, with about </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6024559/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">15% of people</span></a><span style="font-weight: 400"> experiencing debilitating fear and nervousness at some time in their lives.</span></p><p><span style="font-weight: 400">Anxiety is often comorbid with depression, a condition marked by apathy and sadness. In 2017, </span><a href="https://www.nimh.nih.gov/health/statistics/major-depression.shtml" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">7.1% of US adults</span></a><span style="font-weight: 400"> had at least one major depressive episode. Countless more suffer from mild or moderate periods of depression.</span></p><p><span style="font-weight: 400">I should reiterate that both anxiety and depression are </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6700255/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">linked</span></a><span style="font-weight: 400"> to insomnia. It’s a bit of a “chicken or the egg” scenario. Which causes which we aren’t sure, but we do know they come together.</span></p><p><span style="font-weight: 400">There isn’t one cause of anxiety and depression, but too much glutamate (and too little GABA) is certainly part of the picture.</span></p><p><span style="font-weight: 400">That’s where magnesium comes in. Recall that magnesium </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452159/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">downregulates</span></a><span style="font-weight: 400"> NMDA receptors, reducing levels of glutamate in the brain.</span></p><p><span style="font-weight: 400">Consider the following research on magnesium for anxiety:</span></p><ul><li style="font-weight: 400"><span style="font-weight: 400">Magnesium deficient mice </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452159/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">exhibit</span></a><span style="font-weight: 400"> anxious behaviors. When the mice are given magnesium, their behavior normalizes.</span></li><li style="font-weight: 400"><span style="font-weight: 400">A human </span><a href="https://pubmed.ncbi.nlm.nih.gov/16955721/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">study</span></a><span style="font-weight: 400"> found that pre-test jitters increased magnesium loss through urine.</span></li><li style="font-weight: 400"><span style="font-weight: 400">Observational data </span><a href="https://pubmed.ncbi.nlm.nih.gov/19085527/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">link</span></a><span style="font-weight: 400"> low magnesium levels to increased rates of anxiety.</span></li><li style="font-weight: 400"><span style="font-weight: 400">Several </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452159/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">clinical trials</span></a><span style="font-weight: 400"> show mildly positive effects on magnesium supplementation in those vulnerable to anxiety. These trials, however, used magnesium supplements in tandem with other compounds, so it’s hard to isolate the effect. One trial that used magnesium alone (300 mg magnesium citrate for 5 days) found </span><a href="https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.672.9924&amp;rep=rep1&amp;type=pdf" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">no effect</span></a><span style="font-weight: 400"> on pre-test anxiety.</span></li></ul><p><span style="font-weight: 400">Compared to magnesium for anxiety, there’s even better research on magnesium for depression. Probably the best data come from a </span><a href="https://pubmed.ncbi.nlm.nih.gov/28654669/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">randomized controlled trial</span></a><span style="font-weight: 400"> on 126 adults with mild to moderate depression. Compared to placebo, six weeks of magnesium supplements significantly improved depression symptoms.</span></p><p><span style="font-weight: 400">Population data also link higher magnesium intakes to lower rates of depression. This was nicely summarized in this </span><a href="https://pubmed.ncbi.nlm.nih.gov/27807012/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">2017 meta-analysis</span></a><span style="font-weight: 400">.</span></p><h2><strong>How Much Magnesium Should You Get?</strong></h2><p><span style="font-weight: 400">I recommend shooting for 400–600 mg of daily magnesium from diet and supplements. This recommendation is based on </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5786912/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">estimates</span></a><span style="font-weight: 400"> of what our Paleolithic ancestors evolved to thrive upon.</span></p><p><span style="font-weight: 400">If possible, get most of your magnesium through diet. The best sources of magnesium are colored green since magnesium sits at the center of the chlorophyll molecule. (Think leafy vegetables like spinach, swiss chard, and beet greens). Pumpkin seeds, sunflower seeds, squash, and black beans are also </span><a href="https://drinklmnt.com/blogs/health/electrolyte-rich-foods-and-when-to-supplement" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">magnesium-rich foods</span></a><span style="font-weight: 400">.</span></p><p><span style="font-weight: 400">Use an app like Cronometer to tally your daily magnesium intake. Once you have that number, supplement to make up the shortfall. (For example: If you’re getting 300 mg through diet, take 100-300 mg from supplements).</span></p><p><span style="font-weight: 400">I recommend supplementing with magnesium malate. Avoid the poorly-absorbed form, magnesium oxide, unless your sole purpose is to promote bowel regularity.</span></p><p><span style="font-weight: 400">If you’re struggling with sleep, anxiety, or both—and lower doses of magnesium aren’t cutting it—try 500 mg of supplemental magnesium taken with dinner. That’s the dose used in the </span><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3703169/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400">insomnia study</span></a><span style="font-weight: 400">.</span></p><p><span style="font-weight: 400">Although higher doses of magnesium are generally safe for those with healthy kidneys, I believe it’s wise to keep daily magnesium intake between 400–600 mg per day. If you need to go up from there, go slowly, as magnesium can have a laxative effect.</span></p><h2><strong>Magnesium for Sleep and Anxiety</strong></h2><p><span style="font-weight: 400">Optimizing magnesium status won’t improve every case of insomnia and anxiety. Even if it does help, it probably won’t fix things completely.</span></p><p><span style="font-weight: 400">These are multifactorial problems. They often require testing a variety of solutions.</span></p><p><span style="font-weight: 400">But when it comes to magnesium, the evidence is good enough—and the risk low enough—to pay attention. Getting enough magnesium is an easy way to relax, sleep more soundly, and promote better health. What’s not to like about that?</span></p>