Table 1. Cysteine and glutathione (μM) concentrations in plasma after 2, 4 and 6 months of water or 0.5 and 1% methionine solution treatments.

		Cysteine (μM)	Glutathione (μM)
2 months	CT (N = 10)	354.21±17.5	181.44±17.7
	M05 (N = 10)	310.43±14.7	172.08±19.4
	M1 (N = 10)	297.69±11.2 *	192.36±16.0
p value (ANOVA)		0.029	0.724
4 months	CT (N = 10)	351.42±14.2	202.08±19.0
	M05 (N = 8–9)	317.29±12.4	269.15±28.1
	M1 (N = 9)	348.04±13.5	241.47±31.4
p value (ANOVA)		0.167	0.218
6 months	CT (N = 10)	268.54±13.7	257.95±19.7
	M05 (N = 9–11)	300.52±20.9	264.9± 31.7
	M1 (N = 10–11)	304.69±14.2	254.94±27.4
p value (ANOVA)		0.723	0.964

CT = Control. M05 = Methionine 0.5%. M1 = Methionine 1%. (N = 9–11). *p = 0.03 (Tukey's post hoc test) when compared with CT group in same period. Data are presented as the mean ± SEM.