Micronutrients

"Key vitamins needed during puberty include vitamins D, K, and B12. Adequate calcium intake is essential for building bone and preventing osteoporosis later in life. Young females need more iron at the onset of menstruation, while young males need additional iron for the development of lean body mass. Almost all of these needs should be met with dietary choices, not supplements; iron is an exception. The micronutrient recommendations for preteens ages 9–13 are: vitamin A, 600.0 mcg; vitamin B6, 1.0 mg; vitamin B12, 1.8 mcg; vitamin C, 45.0 mg; vitamin D, 5.0 mcg; vitamin E, 11.0 mg; vitamin K, 60.0 mcg; calcium, 1,300.0 mg; folate, 300.0 mcg; iron, 8.0 mg; magnesium, 240.0 mg; niacin (B3), 12.0 mg; phosphorus, 1,250.0 mg; riboflavin (B2), 900.0 mcg; selenium, 40.0 mcg; thiamine (B1), 900.0 mcg; and zinc, 8.0 mg."