2.2. Study Design, Body Composition Measures, and Blood Sample Collection
CLOT, BLOOD, HEART, LUNG
A human controlled feeding trial with a parallel design was performed in which females (n = 17) and males (n = 11) aged 65+ years were randomized to consume either 3 oz (85 g; n = 15) or 6oz (170.1 g; n = 13) of lean fresh beef within a standardized DASH diet. As previously described, Nutritionist Pro™ software was used to create the study diet. The nutrient composition was based upon the 2015–2020 dietary guidelines for daily caloric intake for older sedentary adults and the DASH eating plan using the National Heart, Lung, and Blood Institute, National Institutes of Health [Body composition and cardiometabolic methods have been previously reported [Participants provided fasted blood samples at weeks 0, 3, 6, 9, and 12. Due to limited resources for analysis, for this study measures were performed at weeks 0, 6, and 12. The fasted blood samples were collected into 10 mL serum separator clot activator tubes (SST Vacutainer; Pulmolab, Northridge, CA, USA) and EDTA-coated tubes (Pulmolab) by a trained phlebotomist. Blood for serum collection was kept at room temperature, allowed to clot, and centrifuged at 650× 