Epidemiological evidence suggests that the diet influences CHD risk, although the protective effects of dietary intervention for patients in diseased states has gained less attention. Secondary care prevention strategies for patients often involves drug therapy that is expensive and can result in undesirable side effects. Therefore, it is potentially beneficial to utilise other strategies, such as diet, in the management of CHD. A systematic review was conducted to examine the effects of specific nutrients on progression of atherosclerosis, vascular function, haemostasis and inflammation in CHD patients. Results show substantial evidence for the efficacy of n–3 oils in reducing cardiovascular mortality and one mechanism may be related to the stabilisation of vulnerable atherosclerotic plaques, although the effects on progression of atherosclerosis, haemostatic activity and vascular inflammation remain equivocal. Promising data also exist for the efficacy of flavonoid-rich foods for improving endothelial function, although strong clinical endpoint evidence is lacking. The variation in the efficacy of certain nutrients in CHD patients may be explained by genetics, existing risk factors, psychosocial factors and methodological issues, although these are often not adequately taken into consideration. We conclude that there is a need to undertake more appropriately designed trials in specific clinical populations, controlling for additional lifestyle and risk factors, examining potential interactions with medications, and also establishing methods to increase compliance to dietary recommendations before specific nutrients can be widely prescribed for secondary prevention. Future research should also utilise techniques that provide a direct measure of atherosclerosis.