- E-cigarette flavorings harm blood vessels and can lead to cardiovascular disease
- Flavoring chemicals used in tobacco products such as e-cigarettes have negative effects on endothelial cells
- When blood vessels are exposed to flavoring additives, blood flow decreases and inflammation increases
E-cigarette flavorings and other tobacco products were found to impair blood vessel function and can increase the risk of cardiovascular disease, reveals a new laboratory research published in Arteriosclerosis, Thrombosis and Vascular Biology, an American Heart Association journal.
In recent times, a rapid rise in the use of e-cigarettes has been seen, partially due to flavoring additives in tobacco products and also of the perception that traditional combustible cigarettes cause less harm.
What are E-cigarettes?
Many studies have been done on the risks of e-cigarettes to lungs, and whether e-cigarettes are dangerous to blood vessels also have been done. However, there are no studies that investigated the risk to blood vessels and how the flavored additives can affect the body.
Scientists at Boston University School of Medicine (BUSM) investigated the short-term effects of flavoring chemicals used in tobacco products such as e-cigarettes on endothelial cells, which are cells that line the blood vessels and inside of the heart.
Nine chemical flavorings are usually used in e-cigarettes, hookah, little cigars, and cigarillos. The nine flavors include:
- Menthol (mint)
- Vanillin (vanilla)
- Eugenol (clove)
- Diacetyl (butter)
- Eucalyptol (spicy cooling)
- Acetylpyridine (burnt flavor)
- Cinnamaldehyde (cinnamon)
- Isoamyl acetate (banana) and
- Dimethylpyrazine (strawberry)
The results showed that all nine flavors were dangerous to cells in the laboratory at the highest levels tested and they also impaired nitric oxide production in endothelial cells in culture (outside of the body).
Nitric oxide is a molecule that inhibits inflammation and clotting, and regulates blood vessels' ability to widen for greater blood flow. However, it was found that flavorings such as menthol, clove, vanillin, cinnamon and burnt flavoring lead to higher levels of an inflammatory marker and lower levels of nitric oxide.
"Increased inflammation and a loss of nitric oxide are some of the first changes to occur leading up to cardiovascular disease and events like heart attacks and stroke, so they are considered early predictors of heart disease," said lead author Jessica L. Fetterman, Ph.D., assistant professor of medicine at Boston University School of Medicine in Massachusetts.
The results show that these flavoring additives can cause some serious health consequences.
Effect of E-cigarettes on the Body
The endothelial cells were collected from volunteers where there were about nine non-smokers or non-e-cigarette users; six non-menthol smokers and six menthol cigarette smokers and later were tested in the laboratory.
The research team found that when blood vessels were exposed to flavoring additives, the normally released chemicals that promote blood flow were decreased, which increased inflammation. Also, endothelial cells from smokers showed the same toxicity as those treated with flavoring chemicals.
"Our work and prior research have provided evidence that flavorings induce toxicity in the lung and cardiovascular systems. Flavorings are also a driver of youth tobacco use and sustained tobacco use among smokers. We still don't know what concentrations of the flavorings make it inside the body," said Fetterman said.
The effects of just the flavorings were tested directly at levels likely to be reached in the body, which is the key strength of the study.
The study limitations were that testing did not heat all the flavorings or include other chemicals used in e-cigarettes. Also, the study measured just the short-term effects of the flavorings and captured these with cells outside the body, and not inside the body.
In 2015, e-cigarette use has rapidly increased among youth with 37 percent of high schoolers reporting they had an e-cigarette. Most youth are up for experimenting the flavored tobacco products.
The American Heart Association (AHA) cautions against the use of e-cigarettes and also calls for new regulations to prevent access, sales and marketing of e-cigarettes to youth.