Dietary total, plant, and animal protein intake in relation to cardiovascular outcomes and inflammatory factors in elderly men: A cross-sectional study

The source and amount of protein intake may influence cardiovascular and inflammatory risk, especially in elders who are often more vulnerable. However, findings on elders have been contradictory. Therefore, we examined the association between dietary total, plant, and animal protein intake in relation to cardiovascular outcomes and inflammatory factors in elderly men. The present cross-sectional study included 357 elderly men. A validated and reliable food frequency questionnaire (FFQ) was used to assess dietary intake. All biochemical factors including triglycerides (TG), fasting blood sugar (FBS), high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL6), and tumor necrosis factor-alpha (TNF-alpha) were measured. Waist circumference (WC) and blood pressure (BP) were also assessed. A significant inverse association was found between animal protein intake and systolic blood pressure (SBP; OR: 0.62; 95% CI: 0.42, 0.91; ptrend = .014). There were significant inverse associations between plant protein intake and WC (OR: 0.34; 95% CI: 0.17, 0.68; ptrend < .001), FBS (OR: 0.51; 95% CI: 0.29, 0.89; ptrend = .018) and Hs-CRP (OR: 0.39; 95% CI: 0.21, 0.70; ptrend = .002). Moreover, significant inverse associations were also found between total protein intake and SBP (OR: 0.54; 95% CI: 0.33, 0.86; ptrend = .010) and total protein and Hs-CRP (OR: 0.50; 95% CI: 0.28, 0.88; ptrend = .015). In elderly men, a high dietary intake of plant protein was associated with lower odds of having high WC, FBS, and Hs-CRP. In addition, high dietary intake of animal protein was associated with higher odds of having a high SBP level, which was explained by higher intake of dairy products.