[Study on the correlation between dietary N-glycolylneuraminic acid intake and chronic inflammation state of body].

Objective: To explore the correlation between dietary N-glycolylneuraminic acid (Neu5Gc) intake and chronic inflammation state of body. Methods: A total of 306 samples of 102 types of food were purchased from a supermarket in Xiamen in September 2019, including grains, meat, poultry, seafood, eggs, beans, dairy products, vegetables and fruits. The content of Neu5Gc in food was determined by liquid chromatography-mass spectrometry. A total of 500 healthy freshmen from Xiamen University were selected by using a simple random sampling method. The food frequency questionnaire was used to investigate the food intake in the past year. The food intake was corrected by 3 consecutive 24-hour recalls, and the amount of Neu5Gc intake was calculated. The concentration of anti-Neu5Gc antibody, C-reactive protein (CRP) and interleukin-6 (IL-6) in serum was detected. Spearman correlation analysis was used to explore the correlation between Neu5Gc intake and anti-Neu5Gc antibody, CRP and IL-6 levels. Results: Neu5Gc was mainly found in red meat and liquid dairy products. The contents of Neu5Gc in beef, lamb and pork were (30.32±2.84), (20.39±4.73) and (5.58±1.04) mg/kg, respectively, and in liquid milk and yogurt were (10.87±1.54) and (6.91±0.24) mg/L, respectively. The M (P25, P75) intake of Neu5Gc for all participants was 4.62 (2.20, 8.60) mg/d. The M(P25, P75) intake of Neu5Gc for males about 6.60(2.83, 10.20) was higher than that for females about [3.84 (1.84, 6.35) mg/d] (P<0.001). The M (P25, P75) of serum anti-Neu5Gc, CRP and IL-6 levels were 3.07 (2.17, 4.14) µg/ml, 0.37 (0.22, 0.87) mg/ml and 61.82 (12.23, 315.30) pg/ml, respectively. Spearman correlation analysis showed that the intake level of Neu5Gc was positively correlated with serum anti-Neu5Gc antibody, CRP and IL-6 levels, with rs values about 0.222, 0.102 and 0.126, respectively (all P values <0.05). Conclusion: Dietary Neu5Gc intake is mainly from red meat and liquid dairy products, and its intake level is positively correlated with chronic inflammatory state of body.