People who puff away on a cigarette soon after waking up in the morning could have a higher risk for developing lung, head and neck cancers than those who enjoy a smoke later, according to two studies.

Scientists at the Penn State College of Medicine looked at 4,776 smokers with lung cancer and 2,835 smokers without cancer, and found that patients who smoked in the first 30 minutes after waking up were 79 percent more likely to have developed cancer when compared to those who waited for at least an hour.

"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," says Joshua Muscat of the Penn State College of Medicine, who led the investigation, in a CNN article.

Researchers found that people who smoked their first cigarette between 31 and 60 minutes after waking up were more than 30 percent more likely to develop lung cancer; the odds increased to nearly 80 percent for those who smoked in their first half-hour awake.

As for head and neck cancers, the subjects were more than 40 percent more likely if they light up in the 31 to 60 minute window, and nearly 60 percent more likely for those who smoked in their first half-hour awake.

In another study published in the same journal, researchers looked at 1,850 smokers, of whom 1,055 had head and neck cancers.

They found that people who smoked in the first half hour were 59 percent more likely to have developed cancer than those who waited for hour.

 "Smokers who light up soon after waking tend to smoke each cigarette more intensively," Cancer Research UK's Professor Robert West said in a BBC article. "So the most likely explanation of 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."