Dietary Intake of Protein by Food Source and Incident Hypertension Among Diverse U.S. Adults: The Multi-ethnic Study of Atherosclerosis (MESA)

Objectives: Higher intake of plant protein has been linked to a lower risk of hypertension, while higher intake of animal protein has been associated with increased risk. However, these relationships have not been well established. Further, the relationship between diversity of protein foods and hypertension risk is mostly unknown. We examined associations of protein intake by food source and protein diversity with incident hypertension. Methods: We evaluated 2,294 US adults in the Multi-Ethnic Study of Atherosclerosis 45-84y who were free of hypertension at baseline. Intakes of protein were assessed using a 120-item food frequency questionnaire. Diversity of protein foods was estimated using the number of protein foods consumed at least once/week and a dissimilarity score reflecting diversity of the attributes of the protein sources consumed. During a median follow up time of 9 y, 1,356 new hypertension cases were identified using blood pressure measurements and medication records. Multivariable-adjusted Cox proportional hazards models and restricted cubic spline analyses were used to examine associations with hypertension risk. Results: After adjusting for sociodemographic, lifestyle, and comorbidity factors, there was a non-linear inverse association between plant protein intake and hypertension risk, with a plateauing ∼24% lower risk associated with ≥ 30 g/day (P for non-linearity:0.03). In contrast, greater intake of animal protein was associated with higher hypertension risk [HR (95% CI) for +20 g/d: 1.12 (1.00, 1.24)]. There was a non-linear inverse association between plant protein count, with ∼25% lower risk associated with intakes of ≥ 2 plant protein foods/week (P for non-linearity: 0.005), while greater dissimilarity in plant protein sources was associated with higher hypertension risk [HR (95% CI) 1.72 (1.06, 2.81)]. There was no association with diversity of animal protein sources and hypertension risk. Findings were consistent across genders and race-ethnicities. Conclusions: In a multi-ethnic cohort of middle-aged adults, higher consumption of plant protein foods were associated with lower risk of hypertension, while greater intake of animal protein was associated with higher hypertension risk. Funding Sources: This research was supported by the American Heart Association.