Relation between concentrations of free glycerol and triglycerides in human sera

The concentrations of total glycerol, unesterified glycerol, and glycerol deriving from triglycerides (triacylglycerols) were measured in 468 fresh human sera from unselected outpatients of a municipal hospital. The distribution mode of free glycerol was log-normal; that of triglycerides was neither normal nor log-normal. A weak but statistically approved correlation between these variables was demonstrated. A comparison of triglyceride concentrations corrected for unesterified glycerol with those based on total glycerol shows that, for the triglycerides determination, analysis for total glycerol and substraction of 0.11 mmol/liter from the resulting value appears to be justified in clinical routine. Subtraction of individual sample-blank values is unnecessary. In a triglyceride concentration range from 1.71 to 2.85 mmol/liter the 95 percentile for the possible error of this procedure ranges from + 0.04 to - 0.08 mmol/liter.