6. Unexplained Weight Loss
Unexplained weight loss of about 10 pounds and more may be associated with the lung cancer disease, or some other type of cancer. This drop in weight may be as a result of the cancer cells using up your energy. It can also result from a shift in the way your body utilizes energy from food. Never write off a drastic change in your weight. You should consult your doctor, in case you happen to notice drastic weight loss, especially if you have not been trying to lose weight.