Table 3. Review of the published research measuring the concentrations of Δ4-dafachronic acid and cholestenoic acid in human and mouse sera.

Concentrations in human serum (nM)
Δ4-dafachronic acid		cholestenoic acid
Mean	Variability	Mean	Variability	References
4.52	1.39 (SD)	223.82	76.96 (SD)	Crick et al., Mol Neurobiol, 2017 [18]
2.51	1.40–3.54 (range)	132.01	105.92–154.14 (range)	Höflinger et al., J Lipid Res, 2021 [21]
5.28	1.21 (SD)	198.69	42.29 (SD)	Abdel-Khalik et al., J Lipid Res, 2017 [22]
4.22	0.017 (technical SD)	201.20	7.15 (technical SD)	Crick et al., Clinical Chemistry, 2015 [23]
Concentrations in mouse serum (nM)
Δ4-dafachronic acid		cholestenoic acid
Mean	Variability	Mean	Variability	References
3.43	1.14 (SD)	6.42	3.00 (SD)	Crick et al., JSBMB, 2019 [19]
4.21	0.18 (SD)	8.55	2.93 (SD)	Griffiths et al., BBA—MCB Lipids, 2019 [20]