Can Sitting In Front Of Computer For Long Period Cause Hair Fall?

Hi, I am 24 years old male 165 cm height. I am working in a BPO concern. We use to sit in front of computer for 10 hours a day. Is this have any impact on my hair fall . for the past 3 months i could see some of my hairs turning white. that too at the middle of my head. please give me an advice. Would be better if you could provide me the best oil available in the market for preventing white hair and dandruff. Thanks a lot for your help.