Expert Review of Molecular Diagnostics, 19(9), 797-807
Considering the evidence addressing the ameliorating effects of either L-carnitine or biotics on metabolic indices, also the reports addressing higher efficacy of concomitant supplementation versus single-therapies, this clinical trial was conducted to assess the effects of L-carnitine + multi-species/multi-strain synbiotic combined supplementation compared to L-carnitine mono-therapy on atherogenic-indices, body composition, visceral obesity, and appetite sensations in 46 metabolically healthy women with obesity, randomly assigned to co-supplementation (L-carnitine-tartrate (2 500 mg/dl) + synbiotic (one capsule/day)) or mono-therapy (L-carnitine-tartrate (2 500 mg/dl) + maltodextrin (one capsule/day)) groups for 8 weeks
The honest answer is: it's more interesting than most peptides in this space, the mechanism is real, there's some legitimate clinical evidence and there are also significant gaps in the data that the internet tends to paper over
GIP may also influence fat metabolism and bone health, though these effects are still being investigated in humans
Natural Toxic Compounds of Foods, 103 (2018)