In a recent randomized, double-blind, cross-over clinical trial, serum growth hormone (hGH) increased 682% above baseline 120 minutes after oral administration of an amino acid-based dietary supplement (SeroVital), p=0.01 vs placebo. In contrast to the mechanism of hGH stimulation by ghrelin, the investigators hypothesize that the supplement suppresses somatostatin, a know inhibitor of both hGH and TSH. To test this hypothesis, the investigators measured triiodothyronine (T3) after administration of the amino acid-base supplement.

Two molecular targets that regulate the synthesis and secretion of human growth hormone (hGH) include 1) ghrelin, an endogenous ligand secreted by the stomach that also has appetite-stimulation properties distinct from its hGH-stimulating effects, and 2) somatostatin, a family of 14 and 28 amino acid peptides that act as a potent noncompetitive inhibitor of the release of hGH. the investigators recently reported that oral administration of a 2.9g/dose of SeroVital, a blend of l-lysine HCl, l-arginine HCL, oxo-proline, N-acetyl-l-cysteine, l-glutamine, and schizonepeta (aerial parts) powder, leads to a significant 682% mean increase in endogenous hGH levels in male and female subjects in a period of 120 minutes following acute consumption. In the work presented here, the investigators seek to characterize the mechanistic target associated with this measured increase in endogenous hGH by SeroVital, which the investigators hypothesize to be somatostatin. The investigators test this hypothesis by assaying thyroid function, a secondary inhibition target of somatostatin. The investigators further compare our findings to ghrelin-based hGH secretagogues.

Inclusion Criteria:

• 12 healthy males and 4 healthy females
• Between 18 and 70 years

Exclusion Criteria:

• Pregnant or nursing
• Taking any chronic medication including birth control pills.