(P02-010-23) Impact of a 12-Week Lentil Dietary Intervention on Inflammation in a Metabolically At-Risk Population

Objectives: Elevated postprandial triglycerides (TG) and inflammation are indicators of impaired metabolic health influenced by visceral adipose tissue (VAT) levels. Consumption of fiber-rich food, such as lentils, along with dietary fat can reduce postprandial fat absorption. However, it is unclear how long-term consumption of fiber-rich foods influences inflammatory responses from postprandial lipemia. The purpose of this study was to determine the effect of long-term lentil consumption on postprandial inflammation from a high fat meal.

Methods: Adults (n=33) aged 18-70 with elevated waist circumference (42.3 inches ± 5.2, mean ± SD) consumed 0 (CON, n=16) or 140 g of lentils (LEN, n=17) daily for 12 weeks. A high-fat meal challenge (50 g FAT, 54 g CHO, 12 g PRO) was repeated pre- and post-intervention with blood collected at fasting and hourly for 5 hours postprandially. Postprandial serum concentrations of interleukin (IL)-1β, IL-6, IL10, IL17-, IL-23, interferon gamma (IFN-γ), tumor necrosis factor-α (TNFα), granulocyte-macrophage colony stimulating factor (GMCSF) and TG were summarized as iAUC values. Bioelectrical impedance analysis was used to measure VAT pre- and post-intervention. All markers were summarized as a delta (d) value representing the change after intervention. Separate linear models were created to test the impact of an interaction between intervention meal and TG on each cytokine, accounting for changes in VAT.

Results: The joint impact of meal and dTG was an important predictor for dIL6 (β = 0.21, p < 0.01), dIL10 (β = 0.34, p = 0.02), dTNFα (β = 0.11, p < 0.01), and dGMCSF (β = 0.50, p = 0.04). Main effects for dTG were present for dIL6 (β = -0.02, p = 0.01) and dIL10 (β = -0.03, p = 0.04). Main effects for meal were present for dIL6 (β = -20.64, p = 0.04) and dGMCSF (β = -81.75, p = 0.02) with LEN decreasing inflammation.

Conclusions: Increased habitual lentil consumption alters the postprandial inflammation response to a high fat meal in a manner codependent on changes in postprandial lipid metabolism. Postprandial TG response positively associated with postprandial inflammation in the LEN diet and negatively in the CON. While lower inflammation is beneficial to metabolic health, more research is needed to understand how to lower postprandial TG responses and the interaction of TG and inflammation responses.

Funding Sources: USDA-ARS Pulse Crop Health Initiative