GLOSSARY

Circulating Fatty Acids describes fatty acids in blood and does not necessarily mean only free forms; esterified fractions may also be included.

Circulating fatty acids occur both as albumin-bound non-esterified molecules and esterified within particle triglycerides and phospholipids. A study reporting a fatty-acid level must identify the measured fraction. A component's percentage in phospholipids differs from its absolute concentration in whole blood; direct comparison without matching fractions and units can be misleading.

Free and non-esterified usually refer here to fatty acids not ester-linked within triglycerides or phospholipids. In blood most travel bound to albumin, so free does not mean entirely unbound or freely water-soluble. This pool is not equivalent to all fatty acids across plasma lipids or to the triglyceride value in a lipid panel.

Between meals and during some activity, adipose lipolysis releases fatty acids for other tissues; insulin and exercise-related hormones influence this flow. Blood concentration reflects release balanced against uptake, not a direct measurement of total fat oxidation. A high sample value alone therefore does not demonstrate body-fat loss or a superior training programme.