Perhaps everything else on this list would be far less problematic if we were not such creatures of habit. In fact, studies have found that even when the risks of a particular bad habit are well-known, people find it hard to quit.
"It's not because they haven't gotten the information that these are big risks," says Cindy Jardine of the University of Alberta. "We tend to sort of live for now and into the limited future — not the long term."
Jardine, who has studied why people cling to bad habits, cites these reasons:
-- Innate human defiance
-- Need for social acceptance
-- Inability to truly understand the nature of risk
-- Individualistic view of the world and the ability to rationalize unhealthy habits
-- Genetic predisposition to addiction
People tend to justify bad habits, she says, by noting exceptions to known statistics, such as: "It hasn't hurt me yet," or, "My grandmother smoked all her life and lived to be 90."