itunes had error and shutdown while updating. when restoring iphone do you lose pics, texts emails etc?

Itunes had an error and shutdown while updating my iphone 4. Itune tells me my phone is in recovery mode and I must use restore before im able to use itunes. I cannot do anything on my phone now. It shows icons telling me to connect to itunes. I want to know if I restore my phone do I lose any photos and that were not backed up yet? or What happens to my contacts and phone numbers?