How much magnesium do people need?

The recommended daily dose of magnesium varies according to a person's age and gender, but an adult male between the ages of 19 and 30 needs 400 milligrams of the mineral per day, states WebMD. An adult nonpregnant female of the same age should consume 310 milligrams per day.

The average human body contains about 25 grams of the mineral, explains WebMD. Magnesium can be used to treat constipation, dyspepsia, high blood pressure during pregnancy and magnesium deficiency. Magnesium deficiency can cause a number of problems including restless leg syndrome, abnormal heart rhythms, seizures, muscle spasms, confusion and nausea, notes the University of Maryland Medical Center.