NUTRIENT LIBRARY

Nutrient Library - Magnesium

Magnesium

What does it do?
How much do you need?
What are the best food sources?
What happens if you don’t get enough?
What happens if you get too much?
What are some recipes that are good sources of magnesium?
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What does it do?

Magnesium is involved in the formation of bone, helps maintain normal muscle and nerve function, keeps heart rhythms normal and participates in more than 300 biochemical reactions in the body. Magnesium also helps the body produce energy and make proteins.

How much do you need?

The following table lists the recommended intake for healthy people based on current scientific information.

Life Stage Group	Recommended Dietary Allowance / Adequate Intake (see note below)	Tolerable Upper Intake Level (UL) The ULs for magnesium represent intake from pharmacological agents only (such as magnesium salts) and do not include intake from food and water.
Infants	(milligrams/day)	(milligrams/day)
0-6 mo. 7-12 mo.	30* 75*	Not determinable for infants due to lack of data on adverse effects in this age group and concern about inability to handle excess amounts. Source should be from food only to prevent high levels of intake.
Children
1-3 yr. 4-8 yr.	80 130	65 110
Males
9-13 yr. 14-18 yr. 19-30 yr. 31-50 yr. 51-70 yr. > 70 yr.	240 410 400 420 420 420	350 350 350 350 350 350
Females
9-13 yr. 14-18 yr. 19-30 yr. 31-50 yr. 51-70 yr. > 70 yr.	240 360 310 320 320 320	350 350 350 350 350 350
Pregnancy
< 18 yr. 19-30 yr. 31-50 yr.	400 350 360	350 350 350
Lactation
< 18 yr. 19-30 yr. 31-50 yr.	360 310 320	350 350 350

NOTE: The table is adapted from the Dietary Reference Intakes reports. Recommended Dietary Allowances (RDAs), when available, are in bold type; Adequate Intakes (AIs) are followed by an asterisk(*). RDAs and AIs may both be used as goals for individual intake. RDAs are set to meet the needs of almost all individuals (97 to 98 percent) in a group. For healthy breastfed infants, the AI is the mean intake. The AI for other life stage and gender groups is believed to cover the needs of all individuals in the group, but lack of data means the percentage of individuals covered by this intake cannot be specified with confidence.
UL = The maximum level of daily nutrient intake that is likely to pose no risk of adverse effects. Unless otherwise specified, the UL represents total intake from food, water and supplements.

What are the best food sources?

Green leafy vegetables, nuts, legumes and whole grains are rich food sources of magnesium. Refined foods generally contain low levels of magnesium. Water can be a source of magnesium—“hard” water contains more than “soft” water. See more food sources and calculate your daily intake.

What happens if you don’t get enough?

Magnesium deficiency is rare in healthy individuals. Magnesium depletion can occur in individuals with diabetes, osteoporosis, chronic alcoholism and malabsorption problems. Severe magnesium depletion can result in numbness, tingling, muscle contractions and cramps, seizures, abnormal heart rhythms, and low blood levels of calcium and potassium (which magnesium regulates at the cellular level).

What happens if you get too much?

Naturally occurring magnesium in food and water has not been shown to cause adverse effects. However, too much magnesium from nonfood sources, such as magnesium salts, has been shown to cause mild to severe toxicity. Symptoms can range from diarrhea, nausea and abdominal cramps to difficulty breathing, extremely low blood pressure and irregular heartbeat.