Background/objectives: Inflammation characterizes obesity and is nutritionally modifiable. The hypothesis of this study is that full-fat dairy foods influence circulating inflammatory and atherogenic biomarkers according to fermentation status.
Subjects/methods: Thirteen overweight subjects participated in five test meals. Single breakfasts containing control low-fat milk or 45 g fat from butter, cream, yoghurt or cheese were tested over 3 weeks. Plasmas obtained 3 and 6 h were later analyzed for inflammatory markers interleukin (IL)-6, IL-1β, tumor necrosis factor-α and high-sensitive C-reactive protein, and atherogenesis-related markers monocyte chemoattractant protein-1, macrophage inflammatory protein-1α, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. A 4-week study in 12 subjects compared the effects on these biomarkers of diets containing ≈50 g dairy fat daily as either butter, cream and ice cream (non-fermented) or cheese plus yoghurt (fermented) dairy foods.
Results: In single-meal study, one outlier subject showed marked increments in biomarkers, hence the following results apply to 12. Within group analysis includes significant falls at 3 h in four inflammatory markers after cream, butter and low fat, and three atherogenesis-related biomarkers after cream. Changes were few after cheese and yoghurt. By 6 h, most values returned to baseline. However, between group analysis showed no differences between the five meals. The 4-week study showed no significant differences in fasting biomarker concentrations between non-fermented and fermented dairy diets.
Conclusions: Single high-fat meals containing sequentially four different full-fat dairy foods did not increase eight circulating biomarkers related to inflammation or atherogenesis. Among subjects, significant falls occurred at 3 h in inflammatory biomarkers after cream and butter but were not specific for full-fat dairy foods. We could not confirm the reported increments in inflammation after fat meals.