L-Arginine Hydrochloride vs. Arginine Alpha-Ketoglutarate (AAKG)
Among 1,304 on-market l-arginine products with an identifiable primary form, 43.2% use L-Arginine Hydrochloride (563 products) and 38.6% use Arginine Alpha-Ketoglutarate (AAKG) (503).
| L-Arginine Hydrochloride | Arginine Alpha-Ketoglutarate (AAKG) | |
|---|---|---|
| Quality tier | Unrated | Unrated |
| L-Arginine by weight | 82.7% | 70.5% |
| Share of market | 43.2% | 38.6% |
| On-market products | 563 | 503 |
| Median declared dose | 413.5 mg middle half: 84.35–827 | 705 mg middle half: 705–1,322.98 |
| Most common brands | Source Naturals, Vitamin World, Best Naturals | Cellucor, Universal, BSN |
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-Arginine Hydrochloride is unrated
Largest disclosed salt form; no human head-to-head bioavailability study of arginine HCl vs free arginine or other salts was located. The best-supported finding on arginine delivery is that oral citrulline raises plasma arginine more effectively than oral arginine itself (a separate compound).
Source: Schwedhelm E et al. 2008, Br J Clin Pharmacol 65(1):51-9, PMID 17662090 (citrulline vs arginine, not salt forms)
Why Arginine Alpha-Ketoglutarate (AAKG) is unrated
Tested in a controlled trial (4g three times daily x8 weeks improved 1RM bench press and Wingate peak power in 35 trained men) but only a time-release vs non-time-release comparison was run, not AAKG against other arginine forms.
Source: Campbell B et al. 2006, Nutrition 22(9):872-81, PMID 16928472
Other l-arginine comparisons
- L-Arginine Hydrochloride vs. Arginine Silicate Inositol Complex (Nitrosigine-type)
- L-Arginine Hydrochloride vs. Arginine Nitrate
- L-Arginine Hydrochloride vs. L-Arginine Pyroglutamate
- Arginine Alpha-Ketoglutarate (AAKG) vs. Arginine Silicate Inositol Complex (Nitrosigine-type)
- Arginine Alpha-Ketoglutarate (AAKG) vs. Arginine Nitrate
- Arginine Alpha-Ketoglutarate (AAKG) vs. L-Arginine Pyroglutamate
- Arginine Silicate Inositol Complex (Nitrosigine-type) vs. Arginine Nitrate
- Arginine Silicate Inositol Complex (Nitrosigine-type) vs. L-Arginine Pyroglutamate
- Arginine Nitrate vs. L-Arginine Pyroglutamate