Postprandial Inflammation and Nuts (PIN) in Older Adults

The aging population is rapidly increasing, and it is important to identify dietary factors that can prevent disease and promote health in this group. Legumes, such as peanuts, are a plant-based food high in protein and unsaturated fat making this a healthy choice but are not consumed frequently enough in older adults. Studies have shown that regular nut consumption is associated with lower adiposity and reduced weight gain, and several dietary pattern studies indicate that nuts and legumes are associated with better bone health. Given these findings, this study will address the postprandial effects of meals with 2 levels of saturated fatty acids (SFA) on metabolic endotoxemia, inflammation and satiety, using a randomized cross-over design. The low SFA meal includes peanuts that are high in monounsaturated fatty acids (MUFA) and the serum endotoxin (lipopolysaccharide, LPS) postprandial response will be compared to a high SFA meal. Baseline measurements will include body composition and serum lipids and glucose. The objectives of the study are: 1. To determine the endotoxin and inflammatory response to a meal with two levels of saturated fat in older individuals with overweight or obesity using a randomized cross-over design; 2. To evaluate satiety and fullness in response to the two meals. It is hypothesized that postprandial circulating endotoxin and inflammation will be higher, and satiety will be similar after the SFA enriched compared to the lower SFA (peanut based) meal. A sample size analysis indicates that 16 participants are needed (α set at 0.05, and power set at 90%) to detect a significant difference in endotoxin between groups. Assuming a 10% dropout, up to 18 individuals will be enrolled. The results of this study have the potential to provide valuable insights into the role of peanuts in promoting health and preventing disease in at-risk older adults.