Secondhand Smoke and Type 2 Diabetes, What's the Connection?
It makes sense that secondhand smoke is associated with an increased risk of respiratory disease and lung cancer, but now researchers say you might add type 2 diabetes to the list. At least among women, those who were exposed to secondhand smoke as children and who never smoked themselves and nonsmoking adults appear to be at increased risk for type 2 diabetes.
Where there’s smoke there’s type 2 diabetes
To arrive at this conclusion, researchers from the National Institute of Public Health in Mexico City evaluated more than 37,000 French women who had never smoked and who did not have type 2 diabetes, cancer, or cardiovascular disease at the beginning of the study in 1992. The women were questioned about their exposure to secondhand smoke during childhood from their parents and during adulthood.
The investigators discovered the following:
- A total of 796 cases of type 2 diabetes were diagnosed in the women in the study, which ran from 1992 through 2007
- Women who had at least one parent who smoked had an 18 percent greater chance of developing type 2 diabetes than those who had parents who did not smoke
- Adult secondhand smoke exposure (at least 4 hours daily) from a spouse or other domestic close contact was associated with a 36 percent increased risk of type 2 diabetes
- This finding held true after investigators took into account the following factors: parental history of diabetes, education, physical activity, body mass index, high blood pressure, high cholesterol, hormone use, alcohol use, red meat consumption, and coffee intake, among others
The findings of this study suggest parents should be aware that their smoking exposes their children to subsequent development of type 2 diabetes. In addition, secondhand smoke continues to be a significant health hazard for adults.
Dangers of second- and thirdhand smoke
Secondhand smoke is defined as the smoke that is exhaled by smokers as well as the smoke that is released from a burning tobacco product. This smoke contains thousands of poisonous compounds, including ammonia, butane, carbon monoxide, cyanide, formaldehyde, lead, and polonium, among others.
In addition to lung disease, secondhand smoke also can cause or contribute to heart disease, asthma (especially among children), leukemia, low-birth weight, sudden infant death syndrome, and middle ear infections among children.
Even after a smoker has left the room, the residue sticks to items in the environment, such as furniture, drapes, clothing, and carpeting, which means children and others living in the home are chronically exposed to the toxins. The smoke that remains on these and other items is sometimes called thirdhand smoke, and even at this stage it is a health hazard.
Given the growing epidemic of type 2 diabetes, everyone should be aware of the risk factors, which include but are not limited to obesity, high cholesterol, high blood pressure, metabolic syndrome, and lack of physical activity. Now it appears exposure to secondhand smoke may be another risk factor for type 2 diabetes.
Lajous M et al. Childhood and adult secondhand smoke and type 2 diabetes in women. Diabetes Care 2013 Jun 11 Epub ahead of print