Intake of fermented dairy products induces a less pro-inflammatory postprandial peripheral blood mononuclear cell gene expression response than non-fermented dairy products: A randomized controlled cross-over trial

Scope It is aimed to investigate how intake of high‐fat meals composed of different dairy products with a similar fat content affects postprandial peripheral blood mononuclear cell (PBMC) expression of inflammation‐related genes, as well as circulating inflammatory markers and metabolites. Methods and results Healthy subjects (n = 47) consume four different high‐fat meals composed of either butter, cheese, whipped cream, or sour cream in a randomized controlled cross‐over study. Fasting and postprandial PBMC gene expression, plasma metabolites, and circulating inflammatory markers are measured. Using a linear mixed model, it is found that expression of genes related to lymphocyte activation, cytokine signaling, chemokine signaling, and cell adhesion is differentially altered between the four meals. In general, intake of the fermented products cheese and sour cream reduces, while intake of the non‐fermented products butter and whipped cream increases, expression of these genes. Plasma amino acid concentrations increase after intake of cheese compared to the other meals, and the amino acid changes correlate with several of the differentially altered genes. Conclusion Intake of fermented dairy products, especially cheese, induces a less inflammatory postprandial PBMC gene expression response than non‐fermented dairy products. These findings may partly explain inconsistent findings in studies on health effects of dairy products.