How Much Magnesium for Seniors? (65+ Dosing Guide)
Informational summary of NIH guidance — not medical advice. Talk to a clinician for personalised dosing, especially with kidney disease or if you take multiple medications.
Seniors fall under the 31+ RDA band: 420mg/day for men, 320mg/day for women, from all sources — the number doesn't rise with age. Older adults absorb less magnesium and often take depleting medications, so 200-400mg of elemental magnesium as glycinate is typical — and declining kidney function makes the 350mg/day supplemental limit matter more; ask your doctor if you have kidney disease.
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How Much Magnesium for Seniors?
The NIH Recommended Dietary Allowance doesn't have a separate tier for older adults. You fall into the same 31+ age band as every other adult: 420mg/day for men and 320mg/day for women, counting food and supplements together. That band starts at 31 and never steps up again — a 70-year-old and a 35-year-old have the identical target number. The RDA doesn't change with age. What changes is your risk profile.
| Age Group | Male | Female |
|---|---|---|
| 19-30 years | 400 mg | 310 mg |
| 31+ years (includes all seniors) | 420 mg | 320 mg |
Source: NIH Office of Dietary Supplements
Why the Same Number Still Means More Risk After 65
Since most adults fall short of the RDA from diet alone, a 200-400mg elemental magnesium supplement is common. Glycinate is the gentlest, best-absorbed form.
"Elemental" means the actual magnesium, not the whole compound. A label can say 2,000mg of magnesium glycinate and still deliver only about 280mg of elemental magnesium. Check which number your label is quoting.
Two things shift with age even though the target number doesn't: intestinal magnesium absorption decreases, and kidney excretion increases.
That matters for the 350mg/day supplemental upper limit. That limit only applies "in healthy adults with normal kidney function" — and that group gets smaller with age.
If you have kidney disease or a reduced eGFR, confirm any magnesium dose with your doctor before supplementing. Magnesium clears through the kidneys.
A gentle way to hit that range: Vitamin Shoppe Magnesium Glycinate 400mg $0.23/day delivers a full clinical-range dose in two tablets and is the gentlest form on the stomach. Compare every verified pick in the full best magnesium guide.
Medications That Make Deficiency More Likely
Older adults are also more likely to take medications that deplete magnesium, compounding the absorption and excretion changes above. Proton pump inhibitors (omeprazole and similar) reduce magnesium absorption with long-term use. Loop and thiazide diuretics increase how much magnesium you lose in urine.
If either applies to you, see the full PPI and magnesium guide or diuretics and nutrient loss guide for dosing specifics.
Leg Cramps at Night
Nocturnal leg cramps get more common after age 50. Magnesium is one of the few supplements with real trial evidence for that specific symptom. See the full leg cramps at night guide for the evidence and dosing.
Frequently Asked Questions
How much magnesium should seniors take?
Same as any other adult: 420mg/day for men, 320mg/day for women, from food and supplements combined — the RDA doesn't rise with age. Deficiency is just more common in seniors, since absorption drops and excretion rises with age. 200-400mg of elemental magnesium as glycinate is a typical supplemental range. If your eGFR is below 60, confirm the dose with your doctor first.
What is the recommended magnesium dosage for seniors?
It's the standard adult RDA: 420mg/day for men, 320mg/day for women, from food and supplements combined, per NIH guidelines. That number holds for every age past 30 — there's no senior-specific target. Most people supplement 200-400mg of elemental glycinate to close the gap.
How much magnesium should a 70-year-old take?
Same band as everyone else: 420mg/day for men, 320mg/day for women — there's no higher tier at 65 or 70. What changes is the margin for error, not the number. Absorption declines and kidney excretion rises with age, and medications like PPIs and diuretics get more common too. Stay conservative on dose and loop in your doctor, especially with any kidney disease.
Which common medications deplete magnesium in seniors?
Two drug classes are common in older adults and both cut into your magnesium. Proton-pump inhibitors like omeprazole reduce absorption with long-term use. Loop and thiazide diuretics increase how much you lose in urine. Ask your doctor about extra magnesium if you're on either — see our PPI-magnesium and diuretics guides for dosing.
Related Guides
- Magnesium Dosage Guide — Full NIH RDA table, clinical trial doses by goal, elemental vs compound explained
- Is 500mg of Magnesium Too Much? — Elemental vs compound math for a specific dose
- Signs of Magnesium Deficiency — Risk factors including age, medications, and testing limits
- PPI-Induced Magnesium Depletion — FDA warning and what to supplement
- Diuretics and Nutrient Loss — Magnesium, potassium, and what's safe to self-supplement
- Leg Cramps at Night — Evidence for magnesium and nocturnal cramps
- Best Magnesium Overall — Every verified pick, ranked by cost per effective dose
Sources
- NIH Office of Dietary Supplements. "Magnesium: Fact Sheet for Health Professionals." ods.od.nih.gov
- FDA Drug Safety Communication. "Low magnesium levels can be associated with long-term use of Proton Pump Inhibitor drugs (PPIs)." 2011. fda.gov