In this study participants will participate in one or two arms of the study. In one arm the participants will be administered GEBT tests that contain different 13C-Spirulina/Egg mix drug lots. In the second arm, the participants will be administered GEBT tests from the same 13C-Spirulina/Egg mix drug lot. All GEBT kit lots will be administered according to the FDA-approved labeling.
The purpose of this study is to collect information regarding lot-to-lot variability in 13C-Spirulina test meal lets and within-subject biological variability.