Magnesium

What it is · too little · too much · daily reference values by country

For reference only. This is not a diagnosis or a prescription. If you have concerns, talk to a doctor or pharmacist.

What it is

Magnesium is a component of bones and teeth, and it acts as a cofactor in very many enzyme systems. (Korea Ministry of Health and Welfare · Korean Nutrition Society)
Magnesium is required in many enzymatic reactions in the body. (European Food Safety Authority)
Magnesium is important for many processes in the body, including regulating muscle and nerve function, blood sugar levels, and blood pressure and making protein, bone, and DNA. (US National Institutes of Health)
Wording taken from the NIH ODS fact sheet by SuppleBoard, with some details left out.

Getting too little

Early symptoms of magnesium deficiency include loss of appetite, nausea, retching, vomiting, fatigue, and weakness. (Korea Ministry of Health and Welfare · Korean Nutrition Society)
Magnesium deficiency may result in low calcium and/or potassium levels which could lead to neurological or cardiac issues. (European Food Safety Authority)
In the short term, getting too little magnesium does not produce obvious symptoms. Low magnesium intakes for a long period of time, however, can lead to magnesium deficiency. (US National Institutes of Health)
Wording taken from the NIH ODS fact sheet by SuppleBoard, with some details left out.
Symptoms of magnesium deficiency include loss of appetite, nausea, vomiting, fatigue, and weakness. Extreme magnesium deficiency can cause numbness, tingling, muscle cramps, seizures, personality changes, and an abnormal heart rhythm. (US National Institutes of Health)
Wording taken from the NIH ODS fact sheet by SuppleBoard, with some details left out.

Getting too much

Taking in too much magnesium salt from nutritional supplements or medicines is said to cause diarrhea, vomiting, abdominal pain, and similar symptoms. (Korea Ministry of Health and Welfare · Korean Nutrition Society)
Magnesium that is naturally present in food and beverages is not harmful. In healthy people, the kidneys can get rid of any excess in the urine. (US National Institutes of Health)
Wording taken from the NIH ODS fact sheet by SuppleBoard, with some details left out.
High intakes of magnesium from dietary supplements and medications can cause diarrhea, nausea, and abdominal cramping. Extremely high intakes of magnesium can lead to irregular heartbeat and cardiac arrest. (US National Institutes of Health)
Wording taken from the NIH ODS fact sheet by SuppleBoard, with some details left out.

Daily reference values by country

Korea · US · EU — tap to open

These tables are daily reference values for healthy people. Numbers in the text above are a different kind of value, and you cannot diagnose yourself from them. How to read RDA, AI and UL

Korea — 2025 Dietary Reference Intakes for Koreans (Ministry of Health and Welfare)

Group	EAR	RNI	AI	UL (non-food sources)
0–5 months			25 mg
6–11 months			55 mg
1–2 years	60 mg	70 mg		60 mg
3–5 years	90 mg	110 mg		90 mg
Male · 6–8 years	130 mg	150 mg		130 mg
Male · 9–11 years	190 mg	220 mg		190 mg
Male · 12–14 years	260 mg	320 mg		270 mg
Male · 15–18 years	340 mg	410 mg		330 mg
Male · 19–29 years	300 mg	360 mg		350 mg
Male · 30–49 years	310 mg	380 mg		350 mg
Male · 50–64 years	310 mg	380 mg		350 mg
Male · 65–74 years	310 mg	380 mg		350 mg
Male · 75+ years	310 mg	380 mg		350 mg
Female · 6–8 years	130 mg	150 mg		130 mg
Female · 9–11 years	180 mg	220 mg		190 mg
Female · 12–14 years	240 mg	290 mg		270 mg
Female · 15–18 years	290 mg	340 mg		330 mg
Female · 19–29 years	240 mg	280 mg		350 mg
Female · 30–49 years	240 mg	280 mg		350 mg
Female · 50–64 years	240 mg	280 mg		350 mg
Female · 65–74 years	240 mg	280 mg		350 mg
Female · 75+ years	240 mg	280 mg		350 mg
Pregnancy	+30 mg	+40 mg		350 mg
Lactation	+0 mg	+0 mg		350 mg

UL (non-food sources) — applies to: Only magnesium from non-food sources such as supplements and medicines (magnesium in food is not included).

US — NASEM (National Academies)

Group	EAR	RDA	AI	UL
1–3 years	65 mg	80 mg		65 mg
4–8 years	110 mg	130 mg		110 mg
Male · 9–13 years	200 mg	240 mg		350 mg
Male · 14–18 years	340 mg	410 mg		350 mg
Male · 19–30 years	330 mg	400 mg		350 mg
Male · 31–50 years	350 mg	420 mg		350 mg
Male · 51–70 years	350 mg	420 mg		350 mg
Male · 71+ years	350 mg	420 mg		350 mg
Female · 9–13 years	200 mg	240 mg		350 mg
Female · 14–18 years	300 mg	360 mg		350 mg
Female · 19–30 years	255 mg	310 mg		350 mg
Female · 31–50 years	265 mg	320 mg		350 mg
Female · 51–70 years	265 mg	320 mg		350 mg
Female · 71+ years	265 mg	320 mg		350 mg
Pregnancy · 14–18 years	335 mg	400 mg		350 mg
Pregnancy · 19–30 years	290 mg	350 mg		350 mg
Pregnancy · 31–50 years	300 mg	360 mg		350 mg
Lactation · 14–18 years	300 mg	360 mg		350 mg
Lactation · 19–30 years	255 mg	310 mg		350 mg
Lactation · 31–50 years	265 mg	320 mg		350 mg
0–6 months			30 mg	—
7–12 months			75 mg	—

UL — applies to: The ULs for magnesium represent intake from a pharmacological agent only and do not include intake from food and water.

EU — EFSA (European Food Safety Authority)

Group	AI	UL
7–11 months	80 mg
1–2 years	170 mg
3–3 years	230 mg
4–9 years	230 mg
Male · 10–17 years	300 mg
Female · 10–17 years	250 mg
Male · 18+ years	350 mg
Female · 18+ years	300 mg
Pregnancy · 18–60 years	300 mg
Lactation · 18–60 years	300 mg
18+ years		250 mg
Pregnancy · 18+ years		250 mg
Lactation · 18+ years		250 mg
1–3 years		—
4–6 years		250 mg
7–10 years		250 mg
11–14 years		250 mg
15–17 years		250 mg

UL — applies to: The ULs for magnesium apply to readily dissociable Mg salts (e.g. chloride, sulphate) and compounds like MgO in food supplements, water or added to foods; it does not include Mg naturally present in foods and beverages.

Sources

EFSA DRV Finder (Dietary Reference Values) · checked 2026-10-07
EFSA DRV Finder — nutrient descriptions · checked 2026-10-07
EFSA Overview on Tolerable Upper Intake Levels (v11, August 2025) · checked 2026-10-07
2025 Dietary Reference Intakes for Koreans, Vol. 3: Minerals (Korean Ministry of Health and Welfare · The Korean Nutrition Society; in Korean) · checked 2026-10-07
2025 Dietary Reference Intakes for Koreans — summary tables (Korean Ministry of Health and Welfare · The Korean Nutrition Society; in Korean) · checked 2026-10-07
NASEM Dietary Reference Intakes summary tables (Appendix J, 2019) · checked 2026-10-07
NIH Office of Dietary Supplements — Magnesium Fact Sheet for Consumers · checked 2026-10-13

The sentences are plain-language summaries of official sources written by SuppleBoard. Each English sentence was checked against the source text by an AI reviewer before publishing. The agencies do not endorse this site. Published 2026-10-16.

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