- Heated tobacco products (HTPs) cause significantly lower levels of oxidative stress and inflammation in eye tissues compared to cigarettes
- Cigarette smoke is proven to be harmful for eye health, increasing the risk of inflammation and oxidative damage
- Smoking is a confirmed risk factor for corneal epithelial diseases
Heated Tobacco Products cause significantly less stress to the eyes than smoking, a world-first study has concluded.
Toxic smoke from cigarettes has long been linked to inflammation and oxidative stress in the eye, both of which are risk factors for more severe ocular diseases such as glaucoma and cataracts. However, less has been known about the risks to vision of nicotine alternatives.
Now, an international team of researchers, led by the Centre of Excellence for the Acceleration of Harm Reduction (CoEHAR) in Catania, has completed the world’s first study analysing the effects of HTPs on the human cornea.
Professor Giovanni Li Volti, Director of CoEHAR in Catania and one of the study’s authors, said: “This analysis specifically highlighted that the amount of oxidised proteins following exposure to heated tobacco products was significantly lower compared to traditional cigarettes.”
HTPs, also known as “heat-not-burn” products, are electronic devices that heat tobacco instead of burning it, releasing a nicotine-containing aerosol rather than smoke.
Smoking linked to severe ocular diseases
The study said: “Tobacco smoke harbours a complex mixture of different chemicals, eventually being responsible for the oxidative stress characterising smokers.
“As a consequence, smoke has been associated with several pathologies characterised by an enhanced inflammatory response. Among them, several ocular diseases have been linked to the toxic effects of smoke exposure on corneal epithelium, in turn triggering an inflammatory and oxidative stress response.
“In the latest years, novel devices named HTPs, emerged as a potential alternative to conventional cigarettes, eventually reducing the exposure to cigarettes’ harmful chemical components.
“Therefore HTPs emerged as a combustion-free nicotine delivery system considered for smoking harm reduction, in turn also releasing an aerosol expected to be much less toxic for the eye.
“To investigate this aspect, we explored the impact of conventional cigarettes and HTPs on the cornea by using standard and clinically relevant conditions.”
Groundbreaking analysis
In the groundbreaking new study, researchers used staining dyes on human corneal tissue to analyse and compare the risks to vision of both smoking and HTPs.
“The uniqueness of this study lies in the use of untargeted proteomics, a methodology designed to identify all proteins involved in the different toxicity mechanisms of traditional cigarettes and heated tobacco products,” Prof. Li Volti said.
In simple terms, this means HTPs present a different toxicity profile to cigarettes. They contain less harmful substances and also release different compounds that have distinct effects on corneas and cells. The researchers found the aerosol released by HTPs has a significantly less harmful effect on the eye than smoke from cigarettes.
Smoking proven to be most harmful to eye health
Meanwhile, their analysis confirmed previous research showing tobacco smoke as extremely harmful to eye health.
It said: “Our data, based on two different experimental models, demonstrated using standard and clinically relevant conditions that smoking has to be accounted as a risk factor for epithelial cornea related diseases.
“Smoke might indeed trigger chronic inflammation, delaying wound healing and exacerbating dry eye syndrome by reducing tear production and damaging the ocular surface.
“Furthermore, chemicals in tobacco smoke can harm the corneal epithelium and impair its function. Corroborating this, we show here that conventional cigarettes enhance oxidative stress, in turn oxidising several proteins downstream. As a result, the epithelium undergoes significant damage, showing also a marked grade of inflammation.” A separate recent study by CoEHAR found that vaping has no significant impact on lung function, regardless of a person’s pattern of vaping.
