Objective: In short-term feeding trials, replacement of other macronutrients with monounsaturated fatty acid reduces blood pressure. However, observational studies have not clearly demonstrated a relationship between monounsaturated fatty acid intake and blood pressure. We report associations of monounsaturated fatty acid intake of individuals with blood pressure in a cross-sectional study. Methods: The International Study of Macro/Micronutrients and Blood Pressure is a cross-sectional epidemiologic study of 4,680 men and women ages 40-59 from 17 population samples in China, Japan, United Kingdom, and United States. Nutrient intake data were based on four in-depth multi-pass 24-hour dietary recalls/person and two timed 24-hour urine collections/person. Blood pressure was measured eight times at four visits. Results: Mean monounsaturated fatty acid intake ranged from 8.1 %kcal (China) to 12.2%kcal (United States). With sequential models to control for possible confounders (dietary, other), linear regression analyses showed significant inverse relationship of total monounsaturated fatty acid intake with diastolic blood pressure for all participants; for 2,238 “non-intervened” individuals, the relationship was stronger. Estimated diastolic blood pressure differences with 2-SD higher monounsaturated fatty acids (5.35 %kcal) were -0.82 mm Hg (P<0.05) for all participants and -1.70 mm Hg (P<0.01) for non-intervened individuals. Inverse associations of dietary total oleic acid (main monounsaturated) with blood pressure in non-intervened individuals were not significant, but those of oleic acid from vegetable sources were stronger and significant (P<0.05). Conclusions: Dietary monounsaturated fatty acid intake, especially oleic acid from vegetable sources, may contribute to prevention and control of adverse blood pressure levels in general populations. Condensed Abstract The associations of monounsaturated fatty acid intake of individuals with blood pressure was investigated in a cross-sectional epidemiologic study of 4,680 men and women ages 40-59 from 17 population samples in China, Japan, United Kingdom, and United States. Linear regression analyses showed significant inverse relationship of total monounsaturated fatty acid intake with diastolic blood pressure. Inverse associations of dietary total oleic acid from vegetable sources with blood pressure in non-intervened individuals were stronger and significant. Dietary monounsaturated fatty acid intake, especially oleic acid from vegetable sources, may contribute to prevention and control of adverse blood pressure levels in general populations. |