How Does A Life Insurance Company Know If You Smoke? 
Well for one thing , in most cases there is a question on the application asking about the use of tobacco . Another way is that in many cases the subject will come up on a paramedic exam , which may also include the collection of blood and urine samples , which will show levels of nicotine etc. . Records from your doctor will be ordered and reviewed by underwriting and they may identify you as a smoker . 