Magnesium and The Brain
The exploration of the gut-brain axis is top of mind these days, however, research is now finding that nutritional deficiencies (common in our culture) can also affect our brain health and contribute to inflammatory conditions within the brain such as; depression, anxiety, alzheimer’s, other memory issues, insomnia, and certain brain related conditions. Recent research focuses on various forms of magnesium supplementation as an adjunct therapy for brain health. According to Dr Emily Deans in her piece Magnesium and The Brain: The Original Chill Pill,
When you start to untangle the effects of magnesium in the nervous system, you touch upon nearly every single biological mechanism for depression.
Although often viewed as such, the brain is not some separate entity within our body, it is connected to our entire system and works synergistically with the nutrients we consume. In his book The Oscillating Brain: ‘How Our Brain Works’ By Timothy D. Sheehan, M.D. 1, Sheehan explains the structure and function of the brain, and breaks down thoroughly how the brain actually works. Sheehan states, “we’ve traditionally viewed the brain as a black box- a system that can be approached only in terms of input and output without actually understanding how it works.”
Sheehan describes the mechanism of magnesium in the brain. Magnesium ions are the ‘gatekeepers’ between NMDA (short for N-methyl D aspartate) neuroreceptors and the cell membranes. These neuroreceptors are responsible for both short-term and long-term memory. Without adequate magnesium, there is essentially no ‘soldiers at the gate’ to block the free flow of ions, and this can lead to cell death, and issues related to short- and long-term recall 2. There are many brain health issues that can be impacted by magnesium.
Magnesium and Stress, Anxiety, and Depression
Magnesium aids the brain with regulation of excessive cortisol related to stress. According to Science Daily, magnesium can help reduce the release of adrenocorticotrophic hormone (ACTH). Magnesium has a direct impact on the function of the transport of protein p-glucoprotein, and can influence the access of corticosteroids to the brain. They concluded that all of these systems are involved in the pathophysiology of stress and depression. 3
Magnesium ions regulate calcium ion flow in neuronal calcium channels, helping to regulate neuronal nitric oxide production. In magnesium deficiency, neuronal requirements for magnesium may not be met, causing neuronal damage which could manifest as depression. 4
Magnesium ion neuronal deficits may be induced by stress hormones, excessive dietary calcium as well as dietary deficiencies of magnesium.
Research is finding a connection between magnesium deficiency and depression. Researchers reviewed case histories showing rapid recovery (less than 7 days) from major depression using 125–300 mg of magnesium with each meal and at bedtime. In these case reviews, magnesium supplementation was found to help with brain conditions such as traumatic brain injury, headache, suicidal ideation, anxiety, irritability, insomnia, postpartum depression, cocaine, alcohol and tobacco abuse, hypersensitivity to calcium, short-term memory loss and IQ loss. They concluded that the possibility that magnesium deficiency may be a huge contributing factor for many mental health and brain related conditions. 5
Additional research concluded that magnesium seems to be effective in the treatment of depression and disturbance in magnesium metabolism might be related to depression. These researchers suggest magnesium supplementation as an adjunctive therapy for those struggling with depression. 6 In even another more recent study, dietary magnesium intake was found to have an association with the risk of depression. This is the first prospective study with 20 years of follow-up to report the association between magnesium intake and the incidence of depression in men. Hospitalized participants receiving moderate dietary magnesium had a significantly decreased risk of getting a hospital discharge diagnosis of depression, vs those receiving the lowest intake of magnesium. 7
Magnesium can also be an adjunctive therapy to post-partum depression (PPD) in women; Discovered when studying the relationship of zinc and magnesium serum levels with PPD. This was a cross-sectional study done on 122 new mothers. Their results showed no statistically significant correlation between zinc serum level and PPD. In contrast, there was a ‘significant inverse relationship between magnesium serum level and PPD, in that the increase of it, decreased PPD risk.’ 8
Aside from depression, there are other areas of brain health magnesium levels can affect, such as migraine headaches, and cognitive decline/memory issues.
Magnesium and Migraine Headaches
Magnesium deficiency has been strongly associated with migraine attacks. With this theory, several potential mechanisms have been proposed, such as:
- Triggered cortical spreading depression
- Decreased release of substance P, stimulated cerebral artery spasm
- An imbalance between mitochondrial energy production and demand
Consequently, the clinical effects of magnesium for migraines has drawn considerable attention. These researchers conducted a meta-analysis to confirm the overall effects of magnesium on migraines. Intravenous magnesium significantly relieved acute migraine within 15 – 45 minutes, 120 minutes, and 24 hours after the initial infusion. Oral magnesium significantly alleviated the frequency and intensity of the migraine. The study concluded that magnesium should be considered as adjunctive therapy for managing migraine attacks. 9
According to Jay Cohen, MD in his book, The Magnesium Solution for Migraine Headaches, 10migraines occur when the muscles of the brain act erratically. Abnormal constriction and dilation of these blood vessels are the cause of migraine pain. The balance of magnesium and calcium in the cells around the arteries determines the relaxation and constriction. Calcium makes muscles constrict whereas magnesium relaxes them. Magnesium blocks the calcium influx into smooth muscle cells, thus regulating blood vessel tone. Magnesium has a relaxing effect on the central nervous system and tempers the actions of the sympathetic nervous system. Magnesium is essential for cells to maintain proper balance of other minerals such as potassium, sodium, and calcium. Cohen suggests magnesium helps migraines by:
- Stabilizing blood vessel membranes
- Inhibits blood vessel contraction in response to chemicals released in the early stages of a migraine
- Inhibits the clumping of platelets
- Reduces the synthesis and release of inflammatory mediators
- Directly relaxes blood vessel tone
Magnesium and Cognitive Decline/Memory
Magnesium is also shown to be effective adjunctive therapy for age related memory loss and Alzheimer’s Disease (AD).
One significant study suggested that elevation of brain magnesium through dietary intake of magnesium exerts substantial positive effects on brain synapses in a mouse model of AD, actually restoring aging brains to their youthful conditions.
The study is the first to show a mechanism for reversing cognitive decline in advanced stage AD mice, and is also the first to show an effective long-term treatment in AD mice. 11
Another study found that in mouse models of the disease, oral administration of magnesium-L-threonate (MgT) alleviated cognitive decline by suppressing the Aβ deposition in amyloid plaques in an APH-1α/1β-dependent manner. Specifically, they found that magnesium ions suppressed amyloid plaque deposits in the brain. These are the plaque deposits associated with Alzheimer’s related memory loss. 12
In his book Magnesium, What Your Doctor Needs to Know, Edwards discusses many of the roles magnesium plays in the facilitation of many of our functions. When it comes to cognition, magnesium regulates a key receptor that helps to support learning and memory. Edwards states that decreased brain electrical activity has been seen in people with low magnesium levels.‘For maintaining plasticity of synapses, adequate magnesium content in cerebrospinal fluid is essential. Magnesium is used for the proper activity of many enzymes within brain cells that control memory and cellular function.’ 13
Although research is new and primarily done on mice, it’s proving positive in the associations between magnesium and brain health in general. According to Edwards, low magnesium levels cannot be diagnosed by lab tests alone. Lab tests cannot give accurate readings of magnesium in your tissue. Relying solely on blood tests, and not on signs and symptoms can lead to a misdiagnosis. If you are struggling with some of these symptoms, supplementing with magnesium (with the help of your doctor) may be helpful.