I feel full even when I eat a little... for past one week .. I feel very active though but loss of apitite and even if I eat a little my stomach is full. I used to eat a lot before but for the past one week  I could not eat anything .. I never  had this issue before ... I am smoker as as well I also  consume alcohol... now I feel more worried about the fact that I could not eat anything . Is this an huge health issue ..