Bulk Glycine vs Nutricost L-Theanine
Side-by-side comparison of scores, ingredients, prices and real customer feedback for Bulk Glycine and Nutricost L-Theanine.
Last verified: 26 Mar 2026 · Based on 43 reviews
Bulk Glycine scores 77.0/100 vs Nutricost L-Theanine at 76.0/100. Bulk Glycine wins on ingredient quality, value for money, certifications. Nutricost L-Theanine is stronger on effectiveness and side effects.
How Do the Scores Compare?
Bulk Glycine Powder
Bulk
|
Nutricost L-Theanine 200mg,...
Nutricost
|
|
|---|---|---|
| Overall Score | 77.0 | 76.0 |
| Effectiveness | 72.0/100 |
82.0/100
Best
|
| Ingredient Quality |
87.0/100
Best
|
75.0/100 |
| Value for Money |
86.0/100
Best
|
62.0/100 |
| Side Effects | 74.0/100 |
90.0/100
Best
|
| Certifications |
68.0/100
Best
|
58.0/100 |
| Best Price |
£4.99
£3.99
Amazon UK →
-20% deal
|
£8.36 Amazon UK → |
| Price per Serving |
£0.02
166 servings
Best value
|
£8.36 1 servings |
| Form | Powder | Capsule |
| Dose | 3000mg glycine per serving | 2.2 Ounces |
| Third-Party Tested | ✓ Yes | ✗ No |
| Reviews Analysed | 27 | 16 |
Bulk Glycine Powder
Pros
- ✓Clinical 3g serving matches research-backed dose for sleep quality improvement
- ✓100% pure glycine — zero fillers, flavourings, or additives
- ✓Excellent cost-per-serving: 166 servings at a competitive UK price
- ✓GMP certified and third-party tested; made in the UK with strong brand transparency
Cons
- ✗Individual response varies significantly — some users report glycine as stimulating rather than sedating
- ✗At least one Reddit user reported anhedonia and worsened sleep at 3g daily; personal titration advised
- ✗No NSF or Informed Sport certification — relevant for competitive athletes
- ✗Prop 65 heavy-metal concerns raised by one user; COA should be requested for long-term high-dose use
Best For
Nutricost L-Theanine 200mg, 120 ...
Pros
- ✓Strong anxiety and stress reduction reported across the majority of reviews
- ✓Highly effective for smoothing caffeine jitters and improving focus quality
- ✓Notable sleep improvement, especially when combined with magnesium glycinate
- ✓Well-tolerated with no side effects reported across all 12 reviews
Cons
- ✗Price flagged as expensive relative to equivalent products on the market
- ✗Sleep benefits may take 4–6 weeks to fully manifest for some users
- ✗Third-party testing claimed in marketing copy but contradicted by product specs
- ✗Not vegan — capsule shell may contain gelatin
Best For
Score Breakdown: Bulk Glycine vs Nutricost L-Theanine
Bulk Glycine Powder delivers a clinical 3g dose of pure, additive-free glycine per serving across 166 servings, making it one of the better-value single-ingredient glycine options in the UK market.
What are the key differences?
Frequently Asked Questions
Which is better, Bulk Glycine or Nutricost L-Theanine? ▼
Is Bulk Glycine worth the price compared to Nutricost L-Theanine? ▼
Which has fewer side effects? ▼
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Disclaimer: AIScored provides data-driven comparisons based on publicly available reviews. This is not medical advice. Affiliate links may earn us a commission at no extra cost to you.
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