Strengthening bones is especially important for preteen and teen
girls, because women who don't get adequate calcium and vitamin
D as teens may be at increased risk for developing osteoporosis
later in life. You can work to avoid osteoporosis, which makes
bones brittle, through adequate calcium intake, exercise, and
plenty of fruits, vegetables, and vitamin D throughout your
life. Calcium requirements change during one's lifetime. The
body's demand for calcium is greater during childhood and
adolescence, when the skeleton is growing rapidly, and during
pregnancy and breast-feeding. Postmenopausal women and older men
also need to consume more calcium. According to the National
Institutes of Health, children 1 to 10 years old need 500 to
1,200 mg of calcium each day. Those 11 to 24 years old need
1,200 to 1,500 mg per day. Adults ages 25 to 50 need 1,000 mg a
day, and those 51 and older need up to 1,500 mg per day. Your
body uses vitamin D to absorb calcium. Being out in the sun for
a total of 20 minutes every