I don't seriously suggest that anyone not brush her teeth. However, it's a fact that many people don't take care of their teeth for decades before suffering the consequences. If one lost one tooth every three years, one would probably improve one's oral care. However, with periodontal problems, the teeth often hang on for a really long time, before all failing at pretty much the same time.
Since lots of people don't take care of their teeth even though they know they should, some people will avoid all sunlight.
