http://en.allexperts.com/q/Hair-Loss-1012/telogen-effluvium-duration.htm that iron deficiency can cause telogen-effluvium or hair loss. I wrote an article in March 2011 on this blog about how stress and trauma can cause telogen effluvium as well. Please see my article on Hair loss due to stress.
According to the website listed above, your iron storage level needs to get above "70" for the hair to regrow.
Other websites have mentioned Vitamin C assists with iron absorption; yet, drinking tea can interfere with iron absorption.
Red meats and organ meats are supposed to be good sources of iron.
The Centers for Disease Control and Prevention suggest a standard adult dose of 50 to 60 mg of iron, two times per day for the treatment of anemia.
Feeling cold all the time can be a sign of iron deficiency.