Increased Human Growth Hormone After Oral Consumption of an Amino Acid Supplement: Results of a Randomized, Placebo-Controlled, Double-Blind, Crossover Study in Healthy Subjects

Abstract

Background: Human growth hormone (hGH) is best known for influencing bone and muscle growth, as well as body composition, but the use of recombinant hGH is controversial. Amino acids are a potentially safer alternative; however, preliminary investigations of the effects of oral amino acids on hGH release have been inconclusive. Therefore, we tested the effects of a novel blend of amino acids optimized to increase hGH release.

Study question: Does an investigational amino acid supplement affect hGH release?

Study design: This was a randomized, placebo-controlled, double-blind, crossover study that included 16 (12 men, 4 women; age 32 ± 14 years; body mass index 26.4 ± 5.0 kg/m) healthy participants. All participants received both placebo and the amino acid supplement after an overnight fast and completed all study visits. Treatment order was randomized, and each treatment was separated by a 1-week washout period.

Measures and outcomes: The primary outcomes were the percent change in hGH from baseline to 120 minutes and the area under the curve of hGH over baseline. Serum hGH was measured using enzyme-linked immunosorbent assay at baseline and 15, 30, 60, 90, and 120 minutes.

Results: At 120 minutes, hGH levels increased by 682% (8-fold) from baseline and were significantly higher than placebo (P = 0.01). In addition, a significantly higher mean area under the curve was observed for the amino acid supplement compared with the placebo [20.4 (95% confidence interval, 19.9-21.0 ng/mL) vs. 19.7 (95% confidence interval, 18.7-20.6 ng/mL); P = 0.04].

Conclusions: These results show that a single dose of the oral amino acid supplement was sufficient to significantly increase hGH levels in healthy adult men and women. CLINICAL TRIAL REGISTRY:: clinicaltrials.gov NCT01540773.

Conflict of interest statement

Conflicts of interest:

CST, WDJ, and JR have no conflict of interest. ALH provides consultant services for Sierra Research Group, LLC. and Basic Research, LLC. FLG is a consultant for Beachbody, Basic Research, LLC., Eisai, Inc., General Nutrition Corporation, Melior Discoveries, and Techenterprises, is on advisory boards for Baronova, Inc., Curves-Jenny Craig, Gelesis, Microbiome Therapeutics, Novo Nordisk, Novartis, Plensat, and Zafgen, holds stock or stock options in Microbiome Therapeutics, Plensat, and Zafgen, and holds patents in Neuroquest.

Figures

Figure 1.. Percent change in serum hGH concentrations over 120 minutes.

Data are the % change from baseline in serum hGH levels following ingestion of SeroVital® or matching placebo (N=16). After an overnight fast, baseline blood samples were collected at −30, −15, and 0 minutes. Treatment was administered at 0 minutes and blood was collected at 15, 30, 60, 90, and 120 minutes.