Why Do They Take Blood For Life Insurance? 
They take blood for life insurance so that they can detect evidence of tobacco use , drug use , or signs of illness or predisposition to illness . These are all factors that would cause the insurance company to rate you higher due to the increased risk . Partly , they do not trust all applicants to be honest about their vices or health , so use this concrete assessment . Partly , applicants are often unaware of their own health condition . 