Mo Z, et al. - Given metabolic endotoxemia is regarded as a reason for a high-fat diet (HFD)-induced inflammation, researchers investigated if an increased LPS and LPS-mediated cytokine generation in the postprandial blood can be induced by HFD or moderately HFD. From the cross-sectional phenotyping study, 98 volunteers (age: 37.3 ± 1.5 y) were included, and 62 volunteers (age: 26.8 ± 1.2 y) were included from the intervention study (IS). These participants were asked to consume a breakfast comprising 60% kcal fat (HF) and 36% kcal fat (moderately HF), respectively. Only the outcomes from the placebo group were presented for the IS. Findings revealed that among healthy adults consuming a moderately HF meal (36% kcal fat, similar to the typical American diet) or a HF meal (60% kcal fat), the major reason of postprandial inflammation may not be LPS. Experts concluded that postprandial inflammation may be modulated by plasma FFAs. There is a need for careful re-assessment of the popular concept of HFD-induced metabolic endotoxemia.