Generally it used to said that, in an average, the life of smoker is nearly 10 years less than a non-smoker. Later it has been proven by clinical researches that smoking can cause many diseases like heart diseases, lung cancer and etc. so automatically reduction in life span.
That is why insurance companies conduct the nicotine test and persons who are considered as the smokers in test, then insurers collect higher premiums from them. Actually insurance companies conduct nicotine test, in order to know whether claims, which are made in the application form are correct. Nicotine test is the part of the medical screening, because that helps the insurer to finalize the premium to charge. Generally the premium of the non smoker for life insurance and health insurance can be the lower than premium of smoker. So the smoker need to pay higher premiums than the non smokers.
Nicotine test can be conducted by using different samples like blood, urine, or saliva. Detecting the nicotine can take longer time in hair drug test. Hair test to find out the nicotine is expensive one. So it can not be feasible for testing all those who apply for life insurance plan and health insurance plan.
Most of the times urine test is conducted to find out whether the person is smoker or not. Essentially the level of the nicotine can be determined by the cotinine test.
If you want to take the insurance plan, then give away the smoking habit in order to reduce the premium, charged by insurance companies.