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Check magnesium intake vs RDA by age and sex — see mg/day, % of RDA and food sources.
Check magnesium intake vs RDA by age and sex — see mg/day, % of RDA and food sources.
Enter values above and click Calculate — results will appear here with the formula explained.
Magnesium RDA is 400–420 mg for men and 310–320 mg for women 19+ (slightly higher for men over 50), covering 300+ enzymatic reactions from ATP metabolism to muscle relaxation and blood-pressure regulation. This calculator checks intake as percent of RDA — most adults land at 70–80%, making it among the most common shortfalls in Western diets.
Food hierarchy favors small dense packages: pumpkin seeds (~150 mg/oz), almonds (~80 mg/oz), cashews, peanuts, whole grains, beans, dark leafy greens and dark chocolate. Refined grains strip most magnesium (white flour keeps ~25% of whole wheat's), so processing level predicts intake better than calories do.
Why shortfalls rarely cause drama yet matter: overt deficiency (cramps, arrhythmias, seizures) needs severe depletion — alcoholism, diuretics, PPIs, uncontrolled diabetes or malabsorption. But subclinical insufficiency associates with hypertension, insulin resistance, migraines and poor sleep in observational data; correcting from 70% to 100% is low-risk upside.
Supplement forms differ meaningfully: citrate and glycinate absorb well with minimal GI effects; oxide is cheap but poorly absorbed (laxative at doses); topical oils lack absorption evidence. The 350 mg supplemental Upper Limit guards against diarrhea, not toxicity — food has no upper limit since kidneys excrete surplus efficiently.
Interaction web: high-dose calcium and zinc compete modestly for absorption (spread doses, don't fear foods); vitamin D activates magnesium-dependent enzymes, so D-replete status improves magnesium utilization; alcohol and loop/thiazide diuretics waste it renally — drinkers and hypertensives on diuretics should prioritize intake or test RBC magnesium.
At 30 with 300 mg intake against a 400 mg RDA (75%), adding 30 g almonds (~80 mg) reaches 95% — one snack closing the gap. Track a 3-day average including nuts, seeds and greens explicitly; single-day recalls miss the concentrated sources that decide adequacy.
Check magnesium intake vs RDA by age and sex — see mg/day, % of RDA and food sources. Formula: RDA: M 400-420, F 310-320. Example: At 30 male, 300 mg intake: 75% of the 400 mg RDA — add 30 g almonds (~80 mg) to reach 95%.
Magnesium RDA is 400–420 mg for men and 310–320 mg for women 19+ (slightly higher for men over 50), covering 300+ enzymatic reactions from ATP metabolism to muscle relaxation and blood-pressure regulation. This calculator checks intake as percent of RDA — most adults land at 70–80%, making it among the most common shortfalls in Western diets.
Food hierarchy favors small dense packages: pumpkin seeds (~150 mg/oz), almonds (~80 mg/oz), cashews, peanuts, whole grains, beans, dark leafy greens and dark chocolate. Refined grains strip most magnesium (white flour keeps ~25% of whole wheat's), so processing level predicts intake better than calories do.
Why shortfalls rarely cause drama yet matter: overt deficiency (cramps, arrhythmias, seizures) needs severe depletion — alcoholism, diuretics, PPIs, uncontrolled diabetes or malabsorption. But subclinical insufficiency associates with hypertension, insulin resistance, migraines and poor sleep in observational data; correcting from 70% to 100% is low-risk upside.
Supplement forms differ meaningfully: citrate and glycinate absorb well with minimal GI effects; oxide is cheap but poorly absorbed (laxative at doses); topical oils lack absorption evidence. The 350 mg supplemental Upper Limit guards against diarrhea, not toxicity — food has no upper limit since kidneys excrete surplus efficiently.
Interaction web: high-dose calcium and zinc compete modestly for absorption (spread doses, don't fear foods); vitamin D activates magnesium-dependent enzymes, so D-replete status improves magnesium utilization; alcohol and loop/thiazide diuretics waste it renally — drinkers and hypertensives on diuretics should prioritize intake or test RBC magnesium.
At 30 with 300 mg intake against a 400 mg RDA (75%), adding 30 g almonds (~80 mg) reaches 95% — one snack closing the gap. Track a 3-day average including nuts, seeds and greens explicitly; single-day recalls miss the concentrated sources that decide adequacy.
At 30 male, 300 mg intake: 75% of the 400 mg RDA — add 30 g almonds (~80 mg) to reach 95%. A day with pumpkin seeds on salad, beans at lunch and dark chocolate dessert can exceed 100% without supplements.
Last reviewed: September 2026 · Report an error