LONDON -- In the "bad old days," tuberculosis and epidemics of infectious diseases were the main killers. In advanced societies today, the No. 1 killers are cardiovascular problems and various forms of cancer. Some of these diseases can be traced to hereditary causes, but lifestyle and environment are major factors. Although we probably cannot eliminate these factors entirely, we can certainly reduce their effects if we are willing to take serious measures to control the substances that cause us so much harm.
Most advanced societies have been forced by popular pressure to ensure that the worst types of pollution caused by dust, smoke, chemicals and industrial wastes are reduced, but the situation in China and in developing countries shows that much more still needs to be done.
However, tobacco, the biggest killer, is still allowed to thrive in many societies. In 1604 King James I of England colorfully described smoking tobacco as "a custom loathsome to the eye, hateful to the brain, dangerous to the lungs, and in the black, stinking fume thereof, nearest resembling the horrible Stygian smoke of the pit that is bottomless."