Abstract MP054: Associations of Monounsaturated Fat From Plant and Animal Sources With Coronary Heart Disease Risk

Background: The association between monounsaturated fat (MUFA) intake and coronary heart disease (CHD) risk remains unclear. We aimed to investigate whether MUFA from plant foods (MUFA-P) and animal foods (MUFA-A) show different associations with CHD risk in two large prospective studies of U.S. men and women. Method: We calculated MUFA-P and MUFA-A among 60,931 women in the Nurses’ Health Study (1990-2012), and 28,445 men in the Health Professionals Follow-Up Study (1990-2010). Diet was assessed by validated food-frequency questionnaire every 4 years. CHD incidence was self-reported and confirmed by review of medical records or death certificates. Result: MUFA-A (median intake: 5.8-6.1% energy) was highly correlated with saturated fat (SFA; spearman correlation [ r ] =0.81-0.83) but not polyunsaturated fat (PUFA, r =0.04 -0.19), whereas MUFA-P intake (median: 5.3-5.4.9% energy) was strongly correlated with PUFA(r=0.61 for both cohorts) but not SFA ( r =0.20-0.21; All P<0.001). In multivariate models adjusted for demographic, lifestyle, and dietary factors, hazard ratios of CHD (HR, 95% confidence interval[95%CI]) from low to high total MUFA quintiles were 1 (reference), 0.92 (0.83, 1.02), 1.03 (0.93, 1.05), 0.89 (0.79,1.00). 0.95(0.873, 1.08; P trend =0.42). For MUFA P these were 1(reference), 0.98 (0.89, 1.07), 0.90 (0.82, 0.99), 0.85 (0.77, 0.93), and 0.86 (0.78, 0.94; P trend <0.001) and for MUFA-A 1(reference), 1.09 (0.99, 1.20), 1.22 (1.11, 1.35), 1.26 (1.13, 1.39), and 1.33 (1.19, 1.48; P trend <0.001). In the energy-density model, CHD risk was lower when MUFA-P iso-calorically replaced 1% energy from total SFA (HR [95%CI]: 0.96[0.92, 1.00]; P=0.03), with no significant changes when MUFA-A replacing SFA (HR [95%CI]: 1.01[0.95, 1.07]; P=0.76). When grouping fat intake as the sum of animal MUFA plus saturated fat and the sum of plant MUFA plus PUFA, the HR (95%CI) of CHD was 0.96 (0.95, 0.98; P<0.001) for replacing 1% energy from the former with the latter. Conclusion: Because MUFA compositions of animal and plant origins are largely similar, our data suggested other components in plant and animal foods may lead to the observed different associations of MUFA-P and MUFA-A with CHD risk. These findings provided a possible explanation on current controversies regarding MUFA intake and CHD risk, and further support health benefit of MUFA intake.