Thermogenic
Gamma-butyrobetaine (GBB)
Gamma-butyrobetaine is a carnitine precursor with no human trial showing fat-loss, energy, or exercise benefit.
How it counts: Not part of the score
We show it on the label and count it as disclosed, but it never affects Dose, any sub-score or the grade. The basis below explains why.
- Clinical dose
- No established clinical dose
- Safety ceiling
- โ
- Evidence
- weak
- Category
- Thermogenic
Evidence summary
Research confidence: low
No reference dose. Gamma-butyrobetaine (GBB) is the compound the body turns into carnitine, and it is sold as a fat burner said to boost carnitine and cause sweating. No published human trial tests GBB supplements for fat loss, energy or exercise at any dose; human data only show that the kidneys convert it to carnitine (Rebouche 1980).
Research sources
- Significance of renal gamma-butyrobetaine hydroxylase for carnitine biosynthesis in man (Rebouche & Engel, J Biol Chem 1980)(opens in new window)
- ฮณ-Butyrobetaine is a proatherogenic intermediate in gut microbial metabolism of L-carnitine to TMAO (Koeth et al., Cell Metab 2014)(opens in new window)
In mice, gut bacteria turn GBB into TMA/TMAO and chronic dietary GBB accelerated atherosclerosis. Animal data at dietary doses; relevance to 5 mg in humans unknown.