Effects of vaping

Using electronic cigarettes (vaping) is by no means harmless. It can cause definite damage to multiple vital organs in the human body, including the respiratory system, cardiovascular system and brain. Compared to traditional tobacco cigarettes that burn, electronic cigarettes may contain fewer toxic substances, but this does not mean they are safe. 
?? Major Health Risks of E-cigarettes
Affected System    Key Risk Points    Specific Findings and Data Support
Respiratory System     Lung Damage and Airway Diseases     - Triggering Lung Diseases: Compared to those who have never used e-cigarettes, current e-cigarette users have a significantly higher risk of developing chronic obstructive pulmonary disease (COPD) [12†L22-L24]; a large-scale study involving nearly 250,000 people also found that using e-cigarettes alone is associated with a higher risk of COPD [20†L5-L7].
- Damaging Airways and Aggravating Asthma: Evidence suggests that e-cigarettes are associated with an increased risk of asthma, lung inflammation, and damage among non-smokers [10†L29-L31]. E-cigarette aerosol irritates and inflames the respiratory tract, causing symptoms such as coughing, bronchitis, and exacerbating existing asthma [22†L38-L41].
- EVALI Acute Injury: A large-scale outbreak of lung injury related to e-cigarette product use occurred in the United States, resulting in 2,807 hospitalizations and 68 deaths as of February 2020. This epidemic was mainly associated with illegal products containing THC (tetrahydrocannabinol) or "black market" cartridges, with vitamin E acetate being one of the main culprits [19†L26-L33].
Cardiovascular System    Acute Stimulation and Long-Term Risks     - Immediate Physiological Impact: Studies have confirmed that acute exposure to e-cigarettes significantly increases heart rate and blood pressure.
- Accelerating Atherosclerosis: A meta-analysis indicates that e-cigarettes containing nicotine increase arterial stiffness, similar to traditional tobacco [25†L13-L14][25†L18-L20].
- Increasing Cardiovascular Event Risk: Using e-cigarettes is associated with a 31% increase in the overall risk of complex cardiovascular diseases [9†L22-L24]. The research of the National Institutes of Health (NIH) found that e-cigarette users have a 19% increased risk of a specific type of heart failure.
Brain and Nervous System    Addiction and Harm to Adolescent Development     - Nicotine Addiction: The nicotine in e-cigarettes is highly addictive and alters the brain's reward circuit, leading to dependence [19†L45-L47].
- Damaging Adolescent Brain Development: The greatest risk is for adolescents, as nicotine damages the areas of the brain responsible for attention, learning, emotion, and impulse control, which may lead to long-term cognitive and behavioral problems [26†L28-L31].
- As a "Jumping Board" for Smoking: Adolescents who use e-cigarettes are approximately three times more likely to start smoking traditional cigarettes in the future, making it a "gateway" product for nicotine dependence [17†L23-L26].
Other Health Risks    Multi-System Impact    - Cancer Risk: E-cigarette aerosol contains various chemicals classified as carcinogens, including formaldehyde, acetaldehyde, and heavy metals, and long-term inhalation increases the risk of future cancer [23†L11-L14][29†L8-L10].
- Oral Health Problems: May be related to oral injuries, bad breath, gum problems, and tooth sensitivity [17†L33-L35].
- Potential Impact on Young Men: Studies have shown that e-cigarettes may be associated with a decrease in the total sperm count in young men [17†L34-L35].
- Physical Injuries: The battery of the device has a risk of overheating and explosion, which may cause severe injuries such as burns and disfigurement [17†L32].
⚖️ Relative Risks and Uncertainty
E-cigarettes vs. Traditional Cigarettes: This is a relative concept. When evaluating "harm reduction", current evidence indicates that smokers who completely switch from traditional cigarettes to e-cigarettes have less exposure to carcinogens and may have a lower health risk than those who continue to smoke. However, this does not mean that e-cigarettes are safe. Moreover, this behavior pattern is essentially replacing one addictive product with another and does not address the issue of nicotine addiction. 
Dual use and smoking cessation effect: The health risks are the highest for those who use both e-cigarettes and traditional cigarettes simultaneously (dual users). Their risks of developing cardiovascular diseases (increased by 67%) and COPD (risk ratio as high as 3.86) are significantly higher than those of single users. The World Health Organization clearly states that e-cigarettes are not recommended as a smoking cessation tool, and there is insufficient evidence to support their effectiveness as an aid for smoking cessation. They are not approved or recommended as smoking cessation methods by the US Food and Drug Administration. 
The long-term effects are still unclear: Although e-cigarette use has been ongoing for over a decade, as a public health issue, its true impact may not fully manifest for several decades. Therefore, future research is crucial for a comprehensive understanding of its long-term risks. 
Regulation of domestic e-cigarette cartridges: In China, mainstream e-cigarette brands such as RELX have their product and cartridge production and sales strictly regulated by the State Tobacco Monopoly Administration. Compared to the earlier "three-no" black market products, compliant products have certain guarantees for their ingredients and production standards, and the risks are relatively controllable. However, they still contain nicotine, and the addictive nature and most of the health risks mentioned above still exist. 
?? Summary
In conclusion, e-cigarettes are a product that causes known damage to multiple systems in the human body. Although their risk profile is not exactly the same as that of combustible tobacco, the generally higher relative risks and uncertainties make them not suitable as safe general consumer products, especially among non-smokers.