How Much Magnesium Do Kids Need Per Day?

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Magnesium is one of the most plentiful minerals in your body, which needs it for over 300 chemical processes. About half of the magnesium in your body is located in your bones. For children whose bones are still growing and developing rapidly, it is crucial that their diets provide enough magnesium to help them grow healthy and strong.


According to the Linus Pauling Institute, magnesium is used in a variety of functions, especially in the metabolism of energy from food. This is important for children who are very active and need plenty of energy. Magnesium is also important for DNA synthesis, which enables cells to reproduce, helping children’s growing tissues. Finally, magnesium works with vitamin D and calcium to help build strong bones. Vitamin D helps aid the absorption of magnesium into your blood, which then travels to your bones.

Recommended Daily Intake

The proper amount of magnesium is essential, as when children become adults, they should end up with around 15 g of magnesium in their skeleton. According to the National Institutes of Health, children between the ages of 1 and 3 need 80 mg of magnesium a day. Those between 4 and 8 years need 130 mg, while children ages 9 to 13 need 240 mg. Teenage boys need 410 mg, while teenage girls should get 360 mg daily.


Because children should be eating a well-balanced diet, a magnesium deficiency should be rare. However, if you are concerned that your child is not getting enough, try a multivitamin. While dietary sources of magnesium are not dangerous, you should not administer excessive amounts of supplements to children. The tolerable upper intake level for supplemental magnesium is 65 mg daily for children ages 1 to 3, 110 mg for those ages 4 to 8, and 350 mg for those ages 9 to 18.


There are many different dietary sources of magnesium. Because magnesium is produced by the chlorophyll found in green plants, green vegetables are especially high in magnesium. These include broccoli, spinach and chard, foods which children may not like, but do need to eat. Other sound sources include whole grains and nuts, including brown rice, peanuts, almonds and cashews. While animal products like meat and milk have medium levels, refined and processed foods typically have low magnesium content, so you should not rely on these to provide enough of the mineral.