Why Do Insurance Companies Test Blood & Urine?

Before a life insurance company issues you a policy and takes you on as a financial risk, it usually requires you to undergo a thorough medical screening -- a process called underwriting. Depending on your age and the amount of insurance you applied for, the underwriter will request a variety of tests to evaluate your overall health. Blood and urine are sampled to detect a variety of diseases and habits that determine whether or not you represent a higher degree of risk for premature death than the average population.

Urine tests can generally detect the presence of nicotine and alcohol in the body. Smoking habits are especially important to detect, because insurance companies charge higher premiums for smokers due to their elevated mortality statistics. The liver metabolizes nicotine into a variety of compounds that are then flushed out by the kidneys in your urine. The urine test can check for levels of nicotine and cotinine -- a byproduct of nicotine -- to confirm your smoking habits.

A blood test can reveal the presence of the human immunodeficiency virus, or HIV, the virus that causes AIDS. HIV attacks your body's immune system and makes you more vulnerable to infections that can be fatal.

A blood test can reveal elevated blood sugar or cholesterol levels that may be a warning sign for diseases such as high blood pressure, diabetes, heart attack and stroke.

Another test that can be performed with a blood sample is a bilirubin test, more commonly referred to as a liver function test. Elevated levels of the bilirubin pigment may indicate liver damage, liver disease or bile duct blockage.

A urine test can detect the presence of illicit substances such as cocaine, marijuana and other drugs. The presence of dangerous drugs such as cocaine may lead to an immediate denial of the insurance coverage. If the test shows marijuana use, the insurance company may treat you simply as a smoker or it might charge higher premiums or deny coverage on grounds that marijuana use is technically an illegal act under federal law.

A blood sample can be used to perform a blood urea nitrogen test and a urine sample can be used in a creatinine test. Nitrogen is a chemical element, and creatinine is a byproduct of creatine phosphate in muscle tissue. Both tests determine your kidney functions; elevated levels of these elements may suggest renal problems.

Blood tests are typically not sufficient to detect the presence of cancer, but some insurance companies perform a carcinoembryonic antigen test, to evaluate the presence of markers that affect the recurrence of certain cancers. The underwriter typically would have to work with the applicant's doctor to further investigate a potential cancer risk.