TABLE 2.

Model-predicted parameters for retinol kinetics in healthy young adults of European ancestry¹

Parameter	Value
L(2,1)	24.2 ± 39.0
L(5,2)	0.114 ± 0.191
DT(3)	0.113 ± 0.0442
L(5,4)	2.98 ± 5.18
L(6,5)	5.50 ± 2.11
L(5,6)	0.169 ± 0.108
L(10,6)	0.0599 ± 0.0231
L(15,12)	0.110 ± 0.205
DT(13)	0.152 ± 0.0327
L(15,14)	1.43 ± 0.872
P(11)	10.9 ± 5.54

¹Values are means ± SDs, n = 30. Parameters are fractional transfer coefficients [L(I,J)] or the fraction of retinol in compartment J that is transferred to compartment I each day. For example, L(6,5) is the fractional transfer of retinol to compartment 6 (stores) from compartment 5 (plasma) (d⁻¹) and L(5,6) is the fractional transfer of retinol back to plasma from stores (d⁻¹). L(0,11), the fraction of the oral dose of β-carotene that was not absorbed, was calculated as P(11) × L(12,11), where P(11) is a constant. L(0,1) = 0.333 × L(2,1), L(16,15) = L(6, 5), L(15,16) = L(5,6), L(20,16) = L(10,6), and L(2,1) = L(3,2) = L(12,11) = L(13,12). The model is shown in Figure 1. DT(3) and DT(13), delay times in components 3 and 13, respectively.