We have developed a previously published paradigm concerning causation of coronary heart disease, based on the probability that the fundamental cause is a microbe, probably Chlamydia pneumoniae, and that the progress of the disease is influenced by number of accelerating and inhibiting factors. We propose that cigarette smoking acts via respiratory infection, this itself being influenced by immunocompetence resulting from sunlight exposure. We also propose an immuno-enhancing effect of oestrogen and an anti-inflammatory effect of statin therapy. In respect of the geographical variation of coronary heart disease, we emphasize that this must be viewed as part of the bigger picture of a high mortality from all causes in countries of North-west Europe that have a particularly low level of sunlight exposure. Finally, we draw attention to the Albanian, French, Italian, Northern Ireland and Scottish paradoxes which should lead to a major review of the conventional wisdom concerning the aetiogenesis of coronary heart disease.