cut on your alcohol intake if you are heavy drinker or stop taking alcoholic drinks!
Unintentional and unexplained weight loss is definitely not good. One possibility is that you have an eating disorder. In which case taking help from a doctor specialized in treating eating disorders will help. There are many other causes like worms in stool, depression, anorexia nervosa, AIDS, cancers especially colon cancers, drug abuse, infections and loss of appetite. Loss of appetite can again be due to certain medications, drug abuse, depression, AIDS, acute and chronic infections, cancers and hypothyroidism. Either you do not eat well or there is increased metabolism as in hyperthyroid states, HIV, cancer etc. Poor absorption as in irritable bowel syndromes and malabsorption syndromes too is possible. Malabsorption syndromes are seen in intestinal tuberculosis, HIV, tropical sprue, parasites in stool and Whipple’s Disease. Diabetes too can be the cause. Do discuss this with your doctor and get yourself examined. Take care!