Gene tests may one day help target healthy living advice to those people most likely to succumb to risky lifestyles, claim scientists.
It's all in the genes - apparently.
However, others claim that the real reasons people drink heavily, smoke and take drugs are far more complex than simply their genetic makeup.
Poor lifestyle choices cannot simply be blamed on your genes, they say.
In an article in the journal Molecular Psychiatry, experts from the University of Oxford looked at all the evidence so far and concluded there was strong likelihood that certain people had genes which predisposed them to certain personality traits.
They may be naturally more anxious or depressed, say the scientists, and perhaps more likely to take solace in drink, tobacco or drugs.
This research suggests that some people are particularly prone to the kind of unhealthy lifestyles that we know can be a cause of cancer
Dr John Souhami, Cancer Research UK
One particular genetic variant was highlighted, involving a gene linked to the transport of the brain chemical serotonin.
Another link has been found between gene variants and the way the brain processes dopamine - another chemical key to certain personality traits, say the researchers.
Dr Marcus Munaf˛, of the Cancer Research UK GP Research Group at Oxford University, said: "Our study suggests that there's a genetic basis to certain kinds of personality trait, which may be important in influencing whether people take up habits such as smoking or whether they can subsequently give them up."
He said that the finding might help target different people in different ways with healthy living campaigns.
Professor Robert Souhami, Cancer Research UK's head of clinical research, said: "Around half of all cancers are potentially preventable if people were to alter their lifestyles, so finding ways of changing behaviour is one of our key priorities.
"This research suggests that some people are particularly prone to the kind of unhealthy lifestyles that we know can be a cause of cancer."
However, Dr Jonathan Chick, a consultant psychiatrist at the Royal Edinburgh Hospital, who specialises in alcohol problems, told BBC News Online that regardless of the influence of genes, free will still played an important role.
He said: "There is no genetic condition that completely removes free will with respect to drinking or smoking.
"Genes may make someone more likely to get a 'buzz' from alcohol or set up a pattern of behaviour that is more likely to become fixed than another person."
Dr John Maule, a psychologist who specialises in how humans make decisions, said that it was "implausible" to put too much emphasis on the role of genes in unhealthy living.
He told BBC News Online: "In younger people, certainly, it's much more about conforming, fitting in with other groups of young people - which seems to me to be quite far removed from a theory that everything is predetermined, and that you're either a risky person or a non-risky person.
"When it comes to risk it's too simplistic to link risk-taking behaviour to a single gene."