Optimal Diets for Prevention of
Coronary Heart Disease
(JAMA ) 03/02/2003
Context Coronary heart disease (CHD) remains the
leading cause of mortality in industrialized countries and is rapidly
becoming a primary cause of death worldwide. Thus, identification
of the dietary changes that most effectively prevent CHD is critical.
Objective To review metabolic, epidemiologic, and clinical trial
evidence regarding diet and CHD prevention.
Data Sources and Study Selection We searched MEDLINE
through May 2002 for epidemiologic and clinical investigations of
major dietary factors (fat, cholesterol, omega-3 fatty acids, trans-fatty
acids, carbohydrates, glycemic index, fiber, folate, specific foods,
and dietary patterns) and CHD. We selected 147 original investigations
and reviews of metabolic studies, epidemiologic studies, and dietary
intervention trials of diet and CHD.
Data Extraction Data were examined for relevance and quality and
extracted by 1 of the authors.
Data Synthesis Compelling evidence from metabolic
studies, prospective cohort studies, and clinical trials in the
past several decades indicates that at least 3 dietary strategies
are effective in preventing CHD: substitute nonhydrogenated unsaturated
fats for saturated and trans-fats; increase consumption of omega-3
fatty acids from fish, fish oil supplements, or plant sources; and
consume a diet high in fruits, vegetables, nuts, and whole grains
and low in refined grain products. However, simply lowering the
percentage of energy from total fat in the diet is unlikely to improve
lipid profile or reduce CHD incidence. Many issues remain unsettled,
including the optimal amounts of monounsaturated and polyunsaturated
fats, the optimal balance between omega-3 and omega-6 polyunsaturated
fats, the amount and sources of protein, and the effects of individual
phytochemicals, antioxidant vitamins, and minerals.
Conclusions Substantial evidence indicates that
diets using nonhydrogenated unsaturated fats as the predominant
form of dietary fat, whole grains as the main form of carbohydrates,
an abundance of fruits and vegetables, and adequate omega-3 fatty
acids can offer significant protection against CHD. Such diets,
together with regular physical activity, avoidance of smoking, and
maintenance of a healthy body weight, may prevent the majority of
cardiovascular disease in Western populations.