Last reviewed: July 2026 · SecondFyre Alkemy Kitchen
Magnesium is involved in over 300 enzymatic reactions in the human body. It regulates GABA receptors (calming neurotransmitter), supports the HPA axis (your stress response), contributes to bone mineralisation, regulates muscle and nerve function, and supports insulin sensitivity. Which means that when magnesium is low, a lot goes wrong simultaneously — and a lot of what goes wrong looks exactly like perimenopause symptoms.
The best estimate is that up to 70% of adults in developed countries are not meeting the recommended daily intake for magnesium. The symptoms of insufficiency — not clinical deficiency, just insufficiency — include poor sleep, anxiety, muscle cramps, constipation, fatigue, and headaches. Which is also, roughly speaking, the symptom list for perimenopause. The overlap is not coincidental.
What Magnesium Does That’s Specifically Relevant to You
Sleep. Magnesium supports the GABA system — the same system that progesterone supports, which disappears in perimenopause. Low magnesium is directly associated with poor sleep quality. Supplemental magnesium has consistent evidence for improving sleep onset and quality in people with insufficiency.
Anxiety and mood. GABA is inhibitory — it is your brain’s calming system. Magnesium supports GABA receptor function and has demonstrated anxiolytic (anti-anxiety) effects in multiple trials. For women experiencing new anxiety in perimenopause on top of the hormonal neurochemical changes, magnesium is low-risk and worth trying.
Bone health. Approximately 60% of the body’s magnesium is stored in bone. Magnesium is required for both osteoblast (bone building) and osteoclast (bone breaking down) activity, and for vitamin D activation — without adequate magnesium, supplemental vitamin D is less effective. You cannot optimise bone health with calcium and vitamin D alone while ignoring magnesium.
Headaches and migraines. Magnesium deficiency is particularly common in women who experience migraines, and supplementation has evidence for reducing migraine frequency. Hormonal headaches that worsen in perimenopause often respond to magnesium.
Constipation. Magnesium draws water into the gut. Magnesium citrate and magnesium oxide are used specifically for this effect. Magnesium glycinate is better absorbed but has less of a laxative effect.
Why You’re Not Getting Enough From Food Alone
Magnesium is found in dark leafy greens, nuts, seeds, legumes, whole grains, and dark chocolate. The problem is that modern agricultural soil is depleted of magnesium compared to 50 years ago, and food processing removes magnesium substantially. A diet that includes daily leafy greens, nuts, seeds, and whole grains will deliver more magnesium than average — but many women still don’t reach the 320mg daily recommendation even with good diets.
Alcohol reduces magnesium absorption and increases urinary magnesium excretion. Stress increases magnesium use. Diuretics deplete it. The combination of stress + alcohol + a typical modern diet creates the conditions for consistent insufficiency.
Which Supplement Form
If you’re going to supplement — and many women in perimenopause should seriously consider it — form matters. Magnesium oxide is the most common and cheapest form and has the poorest absorption (~4%). Magnesium glycinate (also called bisglycinate) is the best-absorbed form and gentlest on the stomach. Magnesium citrate is well-absorbed and has mild laxative effects. Magnesium malate is good for energy and muscle pain.
For sleep and anxiety, magnesium glycinate taken 1-2 hours before bed at 200-400mg is the evidence-supported approach. Discuss with your doctor before supplementing if you have kidney disease.
Last reviewed: July 2026 · SecondFyre Editorial
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