Beta-Alanine vs Glycine
Performance vs Sleep · evidence-backed comparison
- • Beta-Alanine has the stronger evidence base (strong (multiple rcts / meta-analyses)).
- • Glycine has the broader effect profile across the 9 effect categories.
- • Glycine is cheaper per serving ($0.10 vs $0.30).
- • Glycine has higher bioavailability (better absorption).
Side-by-side traits
| Trait | Beta-Alanine | Glycine |
|---|---|---|
Category | Performance | Sleep |
Active compound | β-alanine | Glycine |
Form available | Powder, Capsule | Powder, Capsule |
Source | synthetic | synthetic |
Typical dose | 3.2–6.4 g daily (split doses) | 3 g before bed |
Dose range | 3.2–6.4 g | 3–5 g |
Loading protocol | — | — |
Best taken with | split into 800 mg doses to reduce tingling | water, 30 min before bed |
Best time of day | any | evening |
Bioavailability How efficiently the body absorbs and utilizes the compound. | High (4/5) | Very High (5/5) |
Onset time | Cumulative: 2–4 weeks | Acute: 30–60 min |
Half-life | ~25 min (plasma) | ~1 hour |
Evidence level Quality and quantity of human research. | Strong (multiple RCTs / meta-analyses) | Moderate (some RCTs) |
Overall effect Subjective effect magnitude. | Moderate (3/5) | Low (2/5) |
Muscle / strength | Moderate (3/5) | Low (2/5) |
Physical energy | High (4/5) | Very Low (1/5) |
Focus / cognition | Very Low (1/5) | Low (2/5) |
Mood / stress | Very Low (1/5) | Moderate (3/5) |
Sleep quality | Very Low (1/5) | High (4/5) |
Immunity | Very Low (1/5) | Very Low (1/5) |
Recovery Post-exercise recovery support. | Low (2/5) | Low (2/5) |
Longevity / healthspan | Very Low (1/5) | Moderate (3/5) |
Safety rating 5 = exceptionally well-tolerated; 1 = significant risk profile. | Very High (5/5) | Very High (5/5) |
Price per serving Approximate USD per typical daily dose. | $0.30 | $0.10 |
Vegan friendly | Yes | Yes |
Gluten free | Yes | Yes |
3rd-party tested | Yes | Yes |
About Beta-Alanine
Buffers muscle acid build-up, extending high-intensity efforts in the 1–4 minute range. The 'tingles' are harmless and fade with use.
About Glycine
Sweet-tasting amino that lowers core body temperature for deeper sleep. Cheap, well-tolerated, and especially useful with magnesium glycinate.
Vetted brands, third-party testing, ships worldwide.
Vetted brands, third-party testing, ships worldwide.
Beta-Alanine safety
Common side effects:
- • Paresthesia (harmless tingling)
Glycine safety
Common side effects:
- • Generally none
Avoid if:
- • Clozapine therapy
Drug interactions:
- • Clozapine
Common uses
- • High-intensity endurance
- • CrossFit
- • HIIT
- • Combat sports
Stacks well with: Creatine Monohydrate, Caffeine, L-Citrulline
Common uses
- • Deep sleep
- • Sleep quality
- • Collagen synthesis
Stacks well with: Magnesium Glycinate, Melatonin
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Medical disclaimer
SupplementDuel is for educational purposes only and is not medical advice. Consult a physician before starting, stopping, or combining supplements — especially if you are pregnant, breastfeeding, take prescription medication, or have a chronic condition.