Causes of Feeling Cold All the Time

I am cold all the time. Sometimes I get so cold that all I can do is take a really hot shower or bath. Then I wrap up in pajamas, a robe, and three or four blankets and just ride it out. This even happens in the summertime. I also cannot stand the wind blowing on me. It has gotten to the point where being so sensitive to the cold interferes with my work and life. What causes this problem, and what can I do?