If you are one of those who compulsively smoke as soon as they wake up in the morning, then you are more likely to develop cancer than those who light up later in the day, says a latest study.

As many as 7,610 smokers were studied, and the results were published in the journal Cancer. The study said that this particular habit affected the person, irrespective of other smoking habits.

According to the study, lighting a cigarette within 30 minutes of waking up, doubles the already high risk of cancer.

Cancer Research UK suggested people who were quick to smoke may inhale more smoke into the lungs, according to a BBC report.

When Scientists at the Penn State College of Medicine, U.S. observed 4,776 smokers with lung cancer and 2,835 smokers without cancer, they concluded the early morning smokers were 79 percent more likely to have developed cancer than those who waited at least an hour.

The logic might lie behind the fact that early morning smokers tend to smoke each cigarette more intensively.

The researchers said that the "time to first cigarette" effect was present even after they statistically adjusted for other factors such as the number of cigarettes smoked in a day, said the report.

Another study in the same journal, that observed 1,850 smokers, 1,055 of whom had head and neck cancers concluded that people who smoked in the first half hour were 59 percent more likely to have developed a tumour than those who waited at least an hour.

The authors of the study are not very sure of the reasons behind the relationship, DrJoshua Muscar, lead researcher established the possibility of higher levels of nicotine and other tobacco toxins in their body, and also the fact that they may be more addicted than smokers who refrain from smoking for half an hour or more.