Though the longevity of Japanese citizens may be relatively well understood, the high smoking rate coupled with the low lung cancer rate has scientists scratching their heads. They call this the Japanese Smoking Paradox.
Smoking rates in Japanese males is higher than that of male U.S. citizens—it’s estimated that over 30 percent of Japanese males smoke. However, Japanese smokers are nearly 7 times less likely to get lung cancer than U.S. smokers. Researchers found that male smokers were 40 times more likely to get lung cancer than non-smokers in the United States. However, when compared to Japan, male smokers were only 6.3 times more likely to develop lung cancer than a male non-smoker in Japan. So while there is definitely a big correlation between smoking and lung cancer, scientists are puzzled as to why the Japanese lung cancer rate is so much lower than that of the United States for smokers. Scientists have tried to answer this paradox with a few possible reasons.
Possible Reasons for the Paradox
- One possible reason for the lower lung cancer rates is the lower alcohol consumption of the average Japanese citizen when compared with citizens of the United States. Alcohol is a very well documented contributor to cancer, and males in the U.S. tend to consume much more than their Japanese counterparts. To make matters worse, the relatively poor diets of males in the West as compared to Japanese males can also contribute to higher rates of cancer.
- Another interesting fact to note is the composition of Japanese cigarettes as compared to the cigarettes of the United States. It is very possible that cigarettes in Japan contain much lower amounts of carcinogens than cigarettes in the U.S., which are made of nearly 70 percent cancer-causing chemicals. Activated charcoal is also found in many filters of Japanese cigarettes, which binds to many dangerous chemicals and prevents them from passing into the lungs of the smoker.
- A third possible reason for the lower rate of cancer incidence might be due to the Japanese diet. Japanese people do not eat meat often, eat in small portions, eat a lot of vegetables and fermented foods, eat a lot of fish, and drink green tea. All this compounded might have a lasting effect in suppressing cancer.