Furan fatty acids are unique, naturally occurring lipids that are found in significant amounts in dietary phospholipids, such as in salmon roe.{13184} CMPF is an endogenous metabolite of furan fatty acids in humans. CMPF is highly albumin-bound and accumulates in the serum of uremic patients to concentrations in excess of 0.2 mM. Its primary effect is to inhibit cellular transport and subsequent deiodination of thyroxine (T4).{13104,13105} CMPF is tightly bound to albumin but only moderately inhibits T4 binding in a direct manner (10-14% at 0.3 mM). However, CMPF effectively displaces competitive T4 binding molecules from albumin, such as acidic drugs and free fatty acids.{13105} Therefore, CMPF may indirectly influence T4 binding to albumin by increasing the serum concentration of competitive binding molecules, particularly free fatty acids such as oleic acid.{13105}