Table 3.

Effect of Met and GAA supplementation on plasma and urinary concentrations of homocysteine, GAA, creatine, and creatinine

		GAA, g/d						P-value1
Item	Met, g/d	0	10	20	30	40	SEM	Met	G-L	G-Q	Met × G-L	Met × G-Q
Plasma
Homocysteine, µM	0	15.4	16.4	16.1	18.5	18.2	1.0	0.27	0.32	0.38	0.003	0.43
	12	16.9	15.6	16.4	13.6	15.8
GAA, mg/L	0	0.98	1.36	2.08	2.63	2.59	0.24	0.06	<0.001	0.62	0.03	0.26
	12	1.19	1.26	1.37	1.85	1.94
Creatine, mg/L	0	26.0	31.0	30.9	31.5	25.9	2.4	0.83	0.42	0.03	0.46	0.07
	12	26.4	28.4	28.0	30.0	29.7
Creatinine, mg/L	0	9.04	9.57	10.19	9.80	9.99	0.32	0.17	<0.001	0.06	0.70	0.12
	12	8.51	8.78	9.23	9.14	9.59
Urine
GAA, mg/L	0	67	81	116	106	65	14	0.99	0.06	0.01	0.21	0.06
	12	63	80	94	95	104
Creatine, mg/L	0	491	618	1,027	829	386	150	0.47	0.35	0.02	0.35	0.03
	12	634	666	861	782	933
Creatinine, mg/L	0	1,546	1,245	1,597	1,174	1,118	161	0.54	0.02	0.89	0.92	0.56
	12	1,404	1,347	1,334	958	1,172

¹G-L, linear effect of GAA; G-Q, quadratic effect of GAA.