Health Effects of the New Tobacco

There are two types of new cigarettes: heated cigarettes, which use tobacco leaves just like cigarettes, and electronic cigarettes, which do not use tobacco leaves. In this issue, we will introduce the health effects of heated cigarettes, including passive smoking, which has recently become known.

◆What are the negative effects of smoking from a young age on health?

On May 31, the National Cancer Center released the results of a survey. When asked about the negative effects of smoking from a young age on health, 40.7% of the respondents knew that smoking from a young age “increases nicotine dependence,” for example. 42.9% knew that it “increases the risk of disease” and 29.5% knew that it “increases the risk of premature death. Although these are things that are scientifically known about cigarettes, it is clear that people do not understand that “smoking from a young age has a negative impact on health.

So far, we have learned many things about cigarette smoke. For example, the smoke contains more than 5,000 chemicals and toxins, including nicotine and carbon monoxide, and about 70 carcinogens, including formaldehyde. And smoking is associated with a great many diseases. For example, it has been linked to many cancers such as lung cancer, esophageal cancer, stomach cancer, and cervical cancer, as well as stroke, periodontal disease, myocardial infarction, diabetes, and many other diseases.

◆How many people use new types of cigarettes?

So, how many people are smoking these days? According to 2019 data, which includes heated cigarettes as well as paper cigarettes, the combined smoking rate for men and women is 16.7%. Looking at the smoking rate among young people in their 20s, the rate is 25.5% for men. The rate for women is 7.6%. Heated cigarettes, which use tobacco leaves, have been available in Japan since 2014, and one research study on the use of heated cigarettes found that the percentage of users in Japan has been increasing year by year, and by 2019, more than 10% of the population will be using heated cigarettes. In addition, by age group, for example, looking at people in their 20s and 60s, we can see that the percentage of users in their 20s is increasing more.

What are heated cigarettes?

Heated cigarettes are used by heating tobacco leaves. When this happens, an aerosol is generated. Aerosols are a combination of gases and particulate matter. At first glance, you might think it is a vapor-like substance, but like cigarettes, it contains nicotine and other substances. For example, carbon monoxide and benzpyrene are reported to be reduced compared to paper cigarettes, while nicotine and formaldehyde, a carcinogen, are reported to be present in about the same amounts as in paper cigarettes. Nicotine is an addictive substance. Even if you switch from cigarettes to heated cigarettes, nicotine dependence will continue. Although the amount of toxic substances is decreasing in some types of cigarettes, it has not been confirmed that the disease is decreasing. Heated cigarettes use substances that are not contained in cigarettes. For example, substances that have been used as additives in foods and medicines but are not known what effects they have when taken into the lungs in large quantities for the first time are also used.

◆What are the risks of passive smoking?

What about the effects of heated cigarettes on people around them? For example, a research paper published in May revealed that heated cigarettes also cause passive smoking. The participants in the study were families of fathers who use paper and heated cigarettes and families of nonsmoker fathers. The study examined whether nicotine was absorbed by the body by measuring the concentration of nicotine metabolites in urine. The results showed that family members of cigarette users had the highest concentrations of urinary nicotine metabolites, followed by family members of heated tobacco users, and family members of nonsmokers had the lowest concentrations. As can be seen by comparing the families of heated cigarette users in the middle of the graph with the families of nonsmokers on the right, heated cigarettes are clearly higher, indicating that there is passive smoking. When we spoke with Kota Katanoda, director of the National Cancer Center’s Institute for Cancer Control, he told us to be careful because “the Corona Disaster has increased the number of people working from home, and there are cases where people use heated cigarettes because they think it is okay to smoke at home even though they were not allowed to smoke at home. Looking at this graph, one might think that the concentration of nicotine metabolites in heated cigarettes is lower than in cigarettes. However, according to Mr. Katanoda, “Previous studies have shown that even if the concentration of toxic substances is reduced, it does not necessarily mean that the risk of passive smoking is reduced.

In the United States, a tobacco company applied to the Food and Drug Administration (FDA) for heated cigarettes as “risk-reducing cigarettes,” and the FDA determined that “there is no evidence that switching from paper cigarettes to heated cigarettes reduces the risk of tobacco-related diseases. In the U.S., heated cigarettes are being treated as having a negative impact on the health of users and those around them because there is no evidence that they reduce the risk of disease, although the amount of toxic substances exposed to them is reduced depending on the type. As more and more is being learned scientifically, it may be necessary to consider what to do about heated cigarettes in Japan from the perspective of protecting the health of those who use them and those around them.