iron, vitamin d may lead to smarter, healthier children Published 13 years ago • 339K plays • Length 4:01 Download video MP4 Download video MP3 Similar videos 4:21 learn english with voa special english - iron, vitamin d may lead to smarter, healthier children 3:59 vitamins: d and the diet 1:00 english in a minute: at your fingertips 1:00 english in a minute: i can feel it in my bones