Table 4.

Metabolites reported by all studies and three out of four studies listed in Table 2 and their associated metabolic pathways.

Metabolite [47] (Meta-Analysis n = 9	Metabolite [10]	Metabolite [2]	Metabolite [48] (Xiu)	Matched Pathways
Alanine	Alanine ↓	Alanine ↑	Alanine ↓	Aminoacyl-tRNA biosynthesis Alanine, aspartate, glutamate metabolism Selenocompound metabolism
Histidine	Histidine ↓	Histidine ↓	Histidine ↓	Aminoacyl-tRNA biosynthesis Histadine metabolism Β-alanine metabolism
Tryptophan	Tryptophan ↓	Tryptophan ↓	Tryptophan ↓	Aminoacyl-tRNA biosynthesis Tryptophan metabolism
Asparagine	Asparagine ↑	Asparagine ↑	Asparagine ↓	Aminoacyl-tRNA biosynthesis Alanine, aspartate, glutamate metabolism
Lysine	Lysine	Lysine ↑	Lysine ↓	Aminoacyl-tRNA biosynthesis Biotin metabolism Lysine degradation
Tyrosine		Tyrosine ↓	Tyrosine ↓	Aminoacyl-tRNA biosynthesis Phenylalanine, tyrosine, tryptophan biosynthesis Ubiquinone and terpenoid-quinone biosynthesis Phenylalanine metabolism Tyrosine metabolism
Threonine	Threonine		Threonine ↓	Aminoacyl-tRNA biosynthesis Valine, leucine, isoleucine biosynthesis Glycine, serine, threonine metabolism
Arginine	Arginine ↑		Arginine ↓	Aminoacyl-tRNA biosynthesis Arginine biosynthesis Arginine and proline metabolism
Methionine	Methionine		Methionine ↓	Aminoacyl-tRNA biosynthesis Cysteine, methionine metabolism
Glutamine		Glutamine ↓	Glutamine ↓	Aminoacyl-tRNA biosynthesis Arginine biosynthesis Alanine, aspartate, glutamate metabolism Glutamine and glutamate metabolism Nitrogen metabolism Glyoxylate and dicarboxylate metabolism Pyrimidine metabolism Purine metabolism
Citrulline	Citrulline	Citrulline		Arginine biosynthesis
Ornithine	Ornithine	Ornithine		Arginine biosynthesis Arginine and proline metabolism Glutathione metabolism

The arrows indicate reported increasing or decreasing trends relative to non-GC controls.