Does Secondhand Smoke Increase the Risk of Breast Cancer?

Breast cancer continues to be the most common type of cancer in Turkey and worldwide. Reminding that statistics show approximately 2.3 million women are diagnosed with breast cancer each year worldwide, General Surgery Specialist Prof. Dr. Neşet KÖKSAL said that a new study points to secondhand smoke as a notable risk factor for breast cancer. Prof. Dr. KÖKSAL said that the study showed that women exposed to cigarette smoke, even if they do not smoke at home or at work, have a 24 percent higher risk of developing breast cancer, adding, “Considering the increase in cigarette smoking among women, this situation makes it necessary to take new measures.”

While genetics and lifestyle habits rank among the top risk factors for breast cancer, a comprehensive meta-analysis published in the British Journal of Cancer shows that exposure to secondhand smoke increases the risk of breast cancer by 24 percent in women who do not smoke. Commenting that this data is extremely noteworthy, Prof. Dr. Neşet KÖKSAL, General Surgery Specialist at Yeditepe University Koşuyolu Hospital, evaluated the findings of the study: “In a meta-analysis evaluating 63 scientific studies published between 1984 and 2022, over 35,000 breast cancer cases were analyzed. The findings revealed that passive smoking at home is one of the factors that most significantly increases the risk of breast cancer.”
“Unfortunately, many women are unaware of this risk, and this link is often overlooked,” said Prof. Dr. KÖKSAL. “Because individuals do not smoke actively, they do not think they are at risk. However, it has been determined that passive smokers carry a similar risk to individuals who smoke.”

The Risk of Cigarette Smoke in the Home is Greater

Sharing an interesting finding from the study, our expert continued: "The risk of breast cancer has increased by 17 percent, especially for women who smoke at home and are therefore exposed to smoke. In addition, the risk has been found to increase by approximately 16 percent in women whose spouses smoke. Furthermore, although the risk is relatively lower for women exposed to smoke in the workplace, there is a significant increase compared to the general population. Therefore, it can be said that women who are passive smokers exposed to cigarette smoke increase their risk of breast cancer regardless of where they are."

Exposure to Cigarette Smoke Increases Breast Cancer Risk

Our general surgery specialist pointed out another striking finding from the study: that risk increases with exposure. "It was already known that there is a direct relationship between the amount of smoking and cancer risk for smokers. The same is true for exposure. A woman exposed to approximately 20 cigarettes a day has an approximately 38 percent increased risk of breast cancer. The risk rises to 29 percent for those who have been passive smokers for 40 years, and up to 50 percent for those with 40 pack-years of exposure, which is extremely striking data. Considering that cigarette use is also increasing among young women, this situation already indicates that a serious picture is inevitable in the coming years." 

Higher Risk for Those Exposed to Cigarette Smoke in Childhood

"Cigarette smoke exposure, especially during pre-adolescence and early adolescence, can cause DNA damage in developing breast tissue. This damage lays the foundation for cellular changes that can turn into cancer years later,“ said our expert, explaining the following about children exposed to smoke: ”The study showed that passive smoking not only in adulthood but also during childhood can increase the risk of breast cancer in later years. It was emphasized that children whose parents smoke are at higher risk later in life."

One in Eight Women Will Face Breast Cancer at Some Point in Their Lives

Reminding us that breast cancer, a significant health threat to women, is prevalent enough to affect one in eight women during their lifetime, our expert said, "Breast cancer is the most common cancer among women worldwide. According to the World Health Organization's (WHO) GLOBOCAN 2020 data, 2.3 million women worldwide were diagnosed with breast cancer in 2020 alone. In the same year, 685,000 women lost their lives to breast cancer."

Our expert reminds us that breast cancer accounts for approximately 24 percent of all cancer cases in women in our country, stating, "Approximately 20,000 women are diagnosed with breast cancer each year in Turkey. Although its incidence increases after the age of 50, we are also seeing breast cancer in women in their 30s, especially in recent years. Therefore, this picture shows that awareness needs to be raised not only among older women but also among young women."

The Chance of Success is Very High in the Early Stages of Breast Cancer

Reminding us that breast cancer patients have a chance of treatment at every stage today, but that treatment success increases significantly with early diagnosis, our expert said, “The 5-year survival rate for breast cancers detected in the early stages is over 90%. This once again highlights the vital importance of participating in screening programs.”

“Smoke-Free Air is a Vital Need”

As the research also reveals, our expert emphasizes that passive smoking is among the modifiable risk factors for breast cancer, such as obesity, alcohol, and a sedentary lifestyle, stating, "Measures must be taken against this threat, which should be taken seriously. Compliance with smoking bans, especially in homes and workplaces, is crucial for protecting children and women. Therefore, women who grew up with parents who smoked, individuals who have spent long periods in homes or workplaces where smoking occurs, and those who live with a spouse or partner who smokes should be particularly sensitive to this issue. Awareness, protection, and early screening can help prevent this silent risk. We must remember that smoke-free environments in our homes, workplaces, and shared living spaces are no longer a choice but a vital necessity.