(RxWiki News) Smoking cigarettes increases the risk of cancer - no news there. The time of day smokers light up can increase their cancer risks, according to new research.
Two recent studies have shown that folks who smoke first thing in the morning - within 60 minutes of waking up - increase their cancer risks substantially. This early morning habit affects the odds of developing both lung and head and neck or oral cancers.
"If you can't quit on your own, get help giving up smoking."
Joshua Muscat, Ph.D., of the Penn State College of Medicine in Hershey, wanted to know why some cigarette smokers get cancer and others don't. He and his colleagues designed a study to try and answer that mystery.
They sought to learn if the time of day the first cigarette was smoked had a bearing on cancer risks. This was examined as a single risk factor for both lung and oral cancers and did not take into account how much and how long a person smoked.
The lung cancer study included 4,775 lung cancer cases, along with 2,835 controls. All participants smoked cigarettes regularly. The head and neck study involved 1,055 oral cancer cases and 795 controls, and all participants were cigarette smokers.
The studies found that the sooner a person smokes after awakening, the higher the risks. Compared to people who lit their first cigarette more than 60 minutes after awakening -
- People who smoked their first cigarette within 30 minutes of waking up were 1.79 times more likely to develop lung cancer
- Those who lit up within 31-60 minutes were 1.31 times more likely to get lung cancer
- For head and neck cancers, those who smoked within 30 minutes were 1.59 times more likely to get the disease
- Smokers who had first cigarette 31-60 minutes after getting up were 1.42 times more likely to develop oral cancer than those who lit up after 60 minutes of awakening
Muscat says that these first-thing smokers may actually be more addicted to tobacco because they have higher levels of nicotine and toxins in their bodies.
He says the root cause of the first cigarette timing may be the result of genetic and personal factors.
This research was first published online in Cancer, a peer-reviewed journal of the American Cancer Society.