Cancer has been the No. 1 cause of death for Japanese since 1981, accounting for one-third of Japanese deaths. One's lifestyle is closely related to the contraction of cancer and one can avoid developing cancer to a large extent by changing one's lifestyle. Thus education can play an important role. Since many types of cancer develop slowly over many years, teaching children about the risk of cancer and the importance of having a healthy lifestyle will go a long way toward reducing cancer.
A report by researchers from the Geneva-based International Union Against Cancer (UICC) says that about 40 percent of cancers can be prevented by adopting a healthy lifestyle. Every year, Feb. 4 is marked as World Cancer Day, led by UICC and its member organizations in 86 nations with the support of the World Health Organization. This year UICC started a campaign "Cancers can be prevented too." WHO estimates that the number of global cancer deaths will increase 45 percent from 2007 to 11.5 million by 2030, up from 7.9 million deaths at present.
It is believed that smoking causes about 30 percent of cancer. "Not smoking" is one of the most effective ways to prevent cancer that is cost-free and is not difficult if one is determined. WHO says: "Tobacco is the single largest preventable cause of cancer in the world today. It causes 80 to 90 percent of all lung cancer deaths, and nearly one-third of all cancer deaths in developing countries." In North America and Europe, the decline in the incidence of cancer in the 1990s is attributed to a decrease in the number of smokers.
In Japan, habitual smokers, taking both sexes into account, stood at 21.8 percent of the population in 2008 — down 5.9 percent from 2003. While the percentage of female smokers was 9.1 percent, the figure for men was a record low 36.8 percent — a drop of 10 percentage points from 2003. Still the percentage in Japan is high compared with that of other developed countries. Teaching children about the importance of nonsmoking is important. Adults should be aware that their smoking habits could induce children to smoke. Not smoking not only serves as a good example for children but also helps prevent their "passive smoking."
People should be aware that drinking too much and some eating habits, including overeating, can cause cancer. It has been known that obesity is linked to colon cancer, cancer of the esophagus and postmenopausal breast cancer.
Research by a study panel of the health ministry has found that people who eat a lot of salt-preserved fish and roes have a high risk of developing not only stomach cancer but also other cancers. The research tracked some 80,000 people in eight prefectures for an average of eight years. It found that people who ingested 61 grams of salt-preserved fish a day are 1.11 times more likely to develop cancer than people who eat 0.8 gram of such food a day and that people who eat 7.3 grams of salt-preserved roe a day are 1.15 times more likely to develop cancer than people who don't eat such food.
Other research by the same panel shows that women who take alcoholic beverages equivalent to at least seven large bottles of beer a week (150 milliliters of alcohol) are 1.75 times more likely to suffer from breast cancer than women who do not drink at all. The research tracked some 50,000 women in nine prefectures for an average of 13 years. Factors such as the onset of menopause were excluded. In terms of alcohol amount, seven large bottles of beer are equivalent to seven "go" of sake (one go being 180 milliliters), 14 glasses of wine or seven glasses of "double" whiskey.
The research findings show that restraint in drinking is effective in preventing cancer. Individuals may have difficulty in trying to adopt a healthy lifestyle. The whole family should take care so that each family member gets meals with balanced nutrition and exercises regularly.
Roughly 20 percent of cancers, including liver cancer and cervical cancer, is caused by virus- or bacteria-related infections. Some types of cancer can be prevented by vaccination or disinfection. According to the health ministry, some 9,000 women are diagnosed as having cervical cancer each year. Caused by human papillomavirus infections, it takes the lives of some 2,400 women every year.
In October, the ministry approved a vaccine to prevent cervical cancer. If the vaccine is given to girls in their early teens, it is believed that it can prevent 70 percent to 80 percent of cervical cancer that would occur when they are in their 20s and 30s. The problem is that this vaccine must be injected three times and costs ¥40,000 to ¥50,000.
The Uonuma city government in Niigata Prefecture has decided to financially help girls who want to receive the vaccination from fiscal 2010. The central government should seriously consider subsidizing the vaccine.