Can tryptophan supplement intake at breakfast enhance melatonin secretion at night?

Table 3 DLMOs in the four conditions (n = 8)

	Day 1 DLMO (h:min)	Day 2 DLMO (h:min)	p value	t value	dz value	Δ DLMO^a (min)
TRP*Bright	22:51 ± 0:11	21:53 ± 0:17	.001	5.12	1.81	+58.5 ± 11.4
Placebo*Bright	22:26 ± 0:12	21:40 ± 0:15	.002	4.89	1.73	+46.6 ± 9.5
TRP*Dim	22:01 ± 0:09	22:24 ± 0:14	.050	2.37	0.84	−22.7 ± 9.6
Placebo*Dim	22:21 ± 0:12	22:35 ± 0:17	.118	1.78	0.63	−13.8 ± 7.8

A DLMO was not detected for four subjects during the sampling period; therefore, their data were excluded from this analysis. All data are shown as the mean ± standard error of the mean. Times for day 1 DLMO and day 2 DLMO are presented as clock time (h:min). Δ DLMO = change in DLMO (min)
DLMO dim light melatonin onset
^aA positive value for Δ means that the DLMO on the second day had advanced from its value on the first day

ISSN: 1880-6805