L-Alanyl-L-Glutamine (dipeptide) vs. Glutamine Alpha-Ketoglutarate
Among 231 on-market l-glutamine products with an identifiable primary form, 28.6% use L-Alanyl-L-Glutamine (dipeptide) (66 products) and 20.3% use Glutamine Alpha-Ketoglutarate (47).
| L-Alanyl-L-Glutamine (dipeptide) | Glutamine Alpha-Ketoglutarate | |
|---|---|---|
| Quality tier | Unrated | Unrated |
| L-Glutamine by weight | 67.3% | — |
| Share of market | 28.6% | 20.3% |
| On-market products | 66 | 47 |
| Median declared dose | 269.2 mg middle half: 67.3–336.5 | 2,000 mg middle half: 1,000–2,000 |
| Most common brands | Gaspari Nutrition, Metabolic Nutrition, VPX | Justified Laboratories, PMD, Universal |
Doses are declared per serving in mg. “By weight” is the share of the ingredient that is the nutrient itself (e.g. elemental magnesium in a magnesium salt).
Why L-Alanyl-L-Glutamine (dipeptide) is unrated
Marketed for solubility and stability; the cited trial tested acute dipeptide ingestion during hydration stress in endurance exercise but not against free glutamine. No head-to-head human bioavailability or efficacy comparison of this form was located in PubMed searches.
Source: Hoffman JR et al. 2010, J Int Soc Sports Nutr 7:8, PMID 20181080
Why Glutamine Alpha-Ketoglutarate is unrated
No head-to-head human bioavailability or efficacy comparison of this form was located in PubMed searches.