Dietary triacylglycerol (TAG)

Dietary triacylglycerols (TAGs) are the predominant form of dietary lipid, consisting of three fatty acids esterified to a glycerol backbone (StatPearls, 2023). In the intestinal lumen, these fats must be emulsified by bile salts and subsequently hydrolyzed by enzymes, primarily pancreatic lipase, into free fatty acids and 2-monoacylglycerols to be absorbed by the intestinal mucosa (NIH, 2022). While they serve as a critical energy source and are necessary for the absorption of fat-soluble vitamins (A, D, E, and K), chronic excessive intake is a major driver of obesity, metabolic syndrome, and cardiovascular disease (PubMed, 2021). Pharmacological strategies typically do not target the fats directly but rather the processes governing their digestion; for instance, the drug Orlistat functions by inhibiting gastric and pancreatic lipases, preventing the breakdown of TAGs and thus reducing their absorption by approximately 30% (PubChem, 2024). This leads to the presence of undigested fats in the distal intestine, which can cause side effects such as steatorrhea and potential deficiencies in lipophilic nutrients.

Other names

TriglycerideDietary fatNeutral fatTriacylglycerols

Inhibition of enzymatic hydrolysis by pancreatic lipase, preventing the breakdown of triacylglycerols into absorbable fatty acids and monoglycerides; sequestration of bile acids to impair lipid emulsification; use of non-absorbable fat substitutes.