Early morning smokers 'twice as likely to develop cancer than those who light up later

Smokers who light up their first cigarettes as soon as they wake up are more likely to develop cancer than those who manage to wait an hour.

A study found they had much higher levels of nicotine than those who put off their first smoke of the day. This effect was independent of other smoking habits.

Scientists said the results could be because smokers who light up straight away draw more intensively on their cigarettes.

Can't wait to light up? Those who smoke first thing are more likely to develop lung, head and neck cancer

The results, published online in the journal Cancer, may help identify smokers who have an especially high risk of developing cancer and would benefit from targeted smoking interventions to reduce their risk.

Doctors have long-warned that cigarette smoking increases one's likelihood of developing various types of cancers.

The addictive chemical nicotine breaks down into cotinine, a molecule linked with cancer risk.

But scientists from the Penn State College of Medicine in Pennsylvania, wanted to know why only some smokers developed cancer.

They studied the relationship between time to first cigarette after waking and developing cancer, regardless of duration of habit and frequency.

The lung cancer analysis included 4,775 lung cancer cases and 2,835 controls, all of whom were regular cigarette smokers.

 

Compared with individuals who smoked more than 60 minutes after waking, people who smoked 31 to 60 minutes after waking were 1.31 times as likely to develop lung cancer

Those who smoked within 30 minutes were 1.79 times as likely to develop lung cancer.

The head and neck cancer analysis included 1,055 head and neck cancer cases and 795 controls.

Compared with people who smoked more than 60 minutes after waking, those who smoked 31 to 60 minutes after waking were 1.42 times as likely to develop head and neck cancer, and those who smoked within 30 minutes were 1.59 times as likely to develop head and neck cancer.

These findings indicate that the need to smoke right after waking in the morning may increase smokers' likelihood of getting cancer.

Cancer Research UK’s Professor Robert West, said: 'Smokers who light up soon after waking tend to smoke each cigarette more intensively.

'So the most likely explanation for this finding is that the sooner a smoker lights up, the more smoke is taken into the lungs, and the higher the level of exposure to cancer causing chemicals.

'This may help estimating levels of tobacco exposure more than just looking at the usual daily cigarette consumption.'

Study leader Dr Joshua Muscat said: 'These smokers have higher levels of nicotine and possibly other tobacco toxins in their body, and they may be more addicted than smokers who refrain from smoking for a half hour or more.

'It may be a combination of genetic and personal factors that cause a higher dependence to nicotine.'