Blood protein status
You want enough of it arriving. Fatty acids do not dissolve in blood; they travel bound. When carrier supply was varied in perfused tissue while release was held constant, NET output still changed — proof that carriage, not the enzymes, can be the limiting step. The reciprocal is measured too: scavenging fatty acids away from the cell with extra carrier prevents the feedback inhibition that free fatty acids otherwise exert on their own release. Carry them off and the brake never engages.
In depth
The blood protein that carries released fat away — without it, fat cannot leave the tissue.
What drives it
Liver increases it.
Albumin is synthesized exclusively by hepatocytes; serum albumin is the classical index of hepatic synthetic function. PMID 29295548
Liver scarring reduces it.
Loss of functional hepatocyte mass in cirrhosis reduces albumin synthesis and lowers serum albumin. doi 10.22416/1382-4376-2022-32-4-7-16
What it drives
It increases Blood flow to fat tissue.
'The supply of free fatty acid (ffa) carrier to the tissue was varied either by variations in the rate of blood flow OR by changes in the albumin concentration of the perfusing blood at constant flow rate. The net production of FFA from the tissue was found to depend on the supply of carrier' (PMID 7195565). ⇒ flow and carrier are two ways of delivering the same thing. PMID 7195565
It reduces Fat re-storage.
The reciprocal test, and it is the strongest evidence on this pathway. 'The inhibition of FFAs on lipolysis is associated with a reduced production of cAMP due to AC inhibition, which can be prevented by reducing intracellular ffa level via extracellular albumin scavenging' (doi 10.3389/fphys.2022.826314). Carry the fatty acids off and the feedback brake never engages. doi 10.3389/fphys.2022.826314
Blends that modulate it
Each blend page names this pathway and carries the study behind its claim.
See it on the map
Open the causal map to follow this pathway upstream and downstream, arrow by arrow, each with its study.