Objective: Abdominal obesity is associated with a fasting proinflammatory condition. However, not much is known of the potential variations in circulating inflammatory markers after food intake. The purpose of the present study was to examine postprandial changes in plasma tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and C-reactive protein (CRP) concentrations in men and their potential associations with fat distribution and metabolic profile variables.
Research methods and procedures: Thirty-eight men were given a high-fat meal in the morning after an overnight fast, and TNF-alpha, IL-6, and CRP levels were measured in plasma at 0, 4, and 8 hours after the meal. Physical and metabolic profiles were also assessed for each participant.
Results: We observed a substantial increase in circulating IL-6 levels (p < 0.0001) after the meal. Although postprandial variations in circulating TNF-alpha levels across time failed to reach statistical significance (p = 0.02), we noted a significant decrease in plasma TNF-alpha concentrations 4 hours (-10%, p < 0.001 vs. 0 hours) after food intake. Plasma CRP levels were not affected by the fat load. We also noted that insulin-sensitive individuals displayed a less pronounced inflammatory response after food intake than insulin-resistant subjects.
Discussion: Results of the present study show that consumption of a high-fat meal leads to an increase in plasma IL-6 concentrations and transient decrease in circulating TNF-alpha levels in overweight men. Our results suggest a possible role of insulin resistance in the modulation of the postprandial inflammatory response, which could, in turn, contribute to worsen the state of insulin resistance.