Health – Proving causation, is much, much more difficult than correlation. Your “facts” say that the act of smoking CAUSES heart disease. I would like to know what you base your opinion on. Please explain the methodology of the study done, or help me find out. I am genuinely curious. Smoking tends to affect one’s health badly, and can cause health problems, some of which can lead to death. Just not as many deaths as the government would like you to believe.