The global prevalence of obesity and
obesity-associated cardiometabolic diseases is a significant public health
burden. Chronic low-grade inflammation in metabolic tissues such as white
adipose tissue (WAT) is linked to obesity and may play a role in disease
progression. The overconsumption of dietary fat has been suggested to modulate
the WAT inflammatory environment. It is also recognised that fats varying in
degree of fatty acid (FA) saturation may elicit differential WAT inflammatory
responses. This information has originated predominantly from animal or cell
models and translation into humans in vivo remains limited. This review will
summarise human intervention studies investigating the effect of dietary fat quantity
and quality on subcutaneous WAT inflammation, with a specific focus on the toll
like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) and nucleotide-binding and
oligomerisation domain-like receptor, leucine-rich repeat and pyrin
domain-containing 3 (NLRP3) inflammasome molecular signalling pathways. Overall,
firm conclusions are hard to draw regarding the effect of dietary fat quantity
and quality on WAT inflammatory responses due to the heterogeneity of study
designs, composition of the diets and participant cohorts recruited. Previous
studies have predominantly focused on measures of WAT gene expression. It is suggested
that future work includes measures of WAT total content and phosphorylation of
proteins involved in TLR4/NF-κB and NLRP3 signalling as this is more
representative of alterations in WAT physiological function. Understanding pathways linking intake of total fat and specific FAs
with WAT metabolic-inflammatory responses may have important implications for public
health by informing dietary guidelines aimed at cardiometabolic risk reduction<br