Other factors, such as pregnancy and illnesses, are also important.Infants (Adequate Intake)0 - 6 months: 200 milligrams per day (mg/day)7 - 12 months: 260 mg/dayChildren and Adolescents1 - 3 years: 700 mg/day4 - 8 years: 1,000 mg/day9 - 18 years: 1,300 mg/dayAdults19 - 50 years: 1,000 mg/day50 - 70 years: Men - 1,000 mg/day; Women - 1,200 mg/dayOver 71 years - 1,200 mg/dayPregnancy and Breast-fee