Content area
Full text
Correspondence to Dr Aseem Malhotra, Lister Hospital, Academy of Medical Royal Colleges, Stevenage, UK; [email protected]
Coronary artery disease pathogenesis and treatment urgently requires a paradigm shift. Despite popular belief among doctors and the public, the conceptual model of dietary saturated fat clogging a pipe is just plain wrong. A landmark systematic review and meta-analysis of observational studies showed no association between saturated fat consumption and (1) all-cause mortality, (2) coronary heart disease (CHD), (3) CHD mortality, (4) ischaemic stroke or (5) type 2 diabetes in healthy adults.1 Similarly in the secondary prevention of CHD there is no benefit from reduced fat, including saturated fat, on myocardial infarction, cardiovascular or all-cause mortality.2 It is instructive to note that in an angiographic study of postmenopausal women with CHD, greater intake of saturated fat was associated with less progression of atherosclerosis whereas carbohydrate and polyunsaturated fat intake were associated with greater progression.3
Preventing the development of atherosclerosis is important but it is atherothrombosis that is the real killer
The inflammatory processes that contribute to cholesterol deposition within the artery wall and subsequent plaque formation (atherosclerosis), more closely resembles a ‘pimple’ (figure 1). Most cardiac events occur at sites with <70% coronary artery obstruction and these do not generate ischaemia on stress testing.4 When plaques rupture (analogous to a pimple bursting), coronary thrombosis and myocardial infarction can occur within minutes. The limitation of the current plumbing approach (‘unclogging a pipe’) to the management of coronary disease is revealed by a series of randomised controlled trials (RCTs) which prove that stenting significantly obstructive stable lesions fail to prevent myocardial infarction or to reduce mortality.5
Dietary RCTs with outcome benefit in primary and secondary prevention
In comparison with advice to follow a ‘low fat’ diet (37% fat), an energy-unrestricted...