Glycine is one of those supplements that sounds too simple to matter. It is the smallest amino acid, it tastes faintly sweet, and it shows up in collagen, gelatin, and just about every protein you eat. That simplicity is exactly why the label aisle gets confusing: a 1,000 mg capsule and a 3,000 mg capsule can look interchangeable when they are not.
I went through the Best Glycine Supplements by reading the supplement facts panels, checking the form and dose per serving, and comparing how each bottle fits into an actual evening routine. No taste tests, no personal use claims, just label-level research and the NC Score system we use across the site.
My overall pick for best glycine supplements is the NOW Supplements, Glycine 1,000 mg, Free-Form. It delivers a straightforward 1,000 mg of free-form glycine per capsule, which makes it easy to split a serving across the evening or take it all at once before bed. My top picks are just below.
Our Top Picks
| Product | NC Score | ||
|---|---|---|---|
| Best Overall NOW Supplements Glycine 1000mg Free-Form Veg Caps | 9.8 | Check Price on Amazon | |
| Best for High Doses Horbäach Glycine 3000mg Powder Capsules for Daily | 9.7 | Check Price on Amazon | |
| Best for budget buyers Life Extension Glycine 1000mg for Sleep Support | 9.7 | Check Price on Amazon | |
| Best for flexible intake BulkSupplements Glycine 3000mg Capsules for Daily | 9.6 | Check Price on Amazon | |
| Best for vegan diets Pure Encapsulations Glycine 180 Capsules for Liver | 9.6 | Check Price on Amazon | |
| Best for research dosing THORNE Glycine 1g per Serving with 250 Capsules | 9.5 | Check Price on Amazon | |
Full Reviews
NOW Supplements Glycine provides 1,000 mg of free-form glycine per serving in vegan capsules, with a non-GMO formula free from common allergens.
Pros
- +1,000 mg free-form glycine per serving
- +Vegan capsules with no gelatin
- +Non-GMO and free from major allergens
Cons
- −No third-party certification program named
- −100 capsules may require frequent repurchasing
Key Facts
Detailed Review
NOW Supplements Glycine delivers 1,000 mg of free-form glycine per serving in a vegan capsule, a straightforward format for anyone wanting a single amino acid without extra ingredients. The free-form version is the simplest molecular shape, so it does not need digestion to be broken down first.
The label carries several allergen exclusions: corn, dairy, egg, gluten, nuts, and soy, plus a non-GMO designation. That makes it easier to slot into a restricted diet. I'd consider this for someone who already tracks ingredient lists closely and wants a clean, one-ingredient capsule.
The main trade-off is the lack of a named third-party certification program, and the 100-count bottle means a daily routine will need restocking before long. I rate it a practical pick for a simple glycine routine, though anyone managing a medical condition should check with a healthcare provider first.
Horbäach Glycine delivers 3,000mg of free-form glycine per serving in quick-release capsules, naturally free of gluten, soy, and artificial flavors.
Pros
- +High 3,000mg glycine dose per serving
- +Free-form amino acid for direct absorption
- +Naturally free of gluten, soy, and lactose
- +Non-GMO with no artificial flavors or preservatives
Cons
- −Large 3,000mg dose likely requires multiple capsules per serving
- −No third-party certification program disclosed on label
- −Capsule form may be harder to swallow than powder
Key Facts
Detailed Review
Horbäach Glycine stands out for its straightforward approach: 3,000mg of free-form glycine per serving in quick-release capsules, with no artificial flavors or preservatives. For anyone looking to add a single amino acid to a daily routine, that dose is substantial compared to many glycine products that offer 500mg or 1,000mg per capsule.
The label also states the formula is naturally free of gluten, wheat, yeast, lactose, and soy, which matters if you are managing multiple food sensitivities. I see this fitting best for someone who already takes a capsule-based regimen and wants a higher-dose glycine option without mixing a powder.
The main trade-off is practical: hitting 3,000mg likely means swallowing several capsules, and the label does not name a third-party certification program. For my money, this suits a straightforward, high-dose glycine routine, though those who prefer powders or smaller pills may want to compare formats.
Life Extension Glycine provides 1000 mg of glycine per capsule, a higher dose than many traditional glycine supplements, in a gluten-free vegetarian capsule.
Pros
- +1000 mg glycine per capsule, higher than many traditional supplements
- +Gluten-free and vegetarian capsule format suits restricted diets
- +Certificate of Analysis available for every product
Cons
- −No third-party certification such as USP or NSF disclosed
- −Serving size not explicitly stated on label
Key Facts
Detailed Review
Life Extension Glycine delivers 1000 mg of glycine per capsule, a dose that stands out against many traditional glycine supplements. Glycine is a semi-essential amino acid with a calming effect on the brain, and this product is formulated to promote relaxation and support the ability to fall asleep. The capsules are gluten-free and vegetarian, which I see working well for anyone managing dietary restrictions.
What I appreciate is the transparency: a Certificate of Analysis is available for every Life Extension product, and the formula is manufactured in the USA with internationally sourced ingredients. The main trade-off is that no third-party certification like USP or NSF is disclosed, so independent verification of purity isn't guaranteed. Also, the label doesn't specify a serving size, so it's unclear whether one capsule equals one serving.
I'd consider this a reasonable pick for someone seeking a straightforward, higher-dose glycine supplement for evening relaxation. If you prefer a product with third-party certification, you may want to look elsewhere.
BulkSupplements Glycine Capsules deliver 3000mg of glycine per serving, taken as four capsules, in a 360-count bottle.
Pros
- +Single-ingredient glycine formula with no added blends
- +Four-capsule serving allows flexible intake adjustment
- +Gluten-free capsule format for gluten-sensitive routines
- +360-count bottle limits how often you reorder
Cons
- −Four capsules per serving means frequent restocking
- −No specific third-party certification program named
- −Large daily capsule count may deter pill-averse routines
Key Facts
Detailed Review
BulkSupplements keeps this one simple: glycine only, dosed at 3000mg per serving, with no filler ingredients to sort through. That single-ingredient approach suits anyone who wants to add glycine to an existing routine without stacking extra compounds.
The serving is four capsules, which is the detail that shapes daily use most. Taking four at once is manageable, but it does mean a 360-count bottle runs out faster than a one- or two-capsule product would. I see this working best for someone already comfortable with a multi-capsule regimen.
The main trade-off is the lack of a named third-party certification program. The label notes cGMP-compliant production and third-party review, but no specific seal like NSF or USP appears, so I'd weigh that against your own standards before buying.
Pure Encapsulations Glycine delivers 180 vegan capsules of the amino acid glycine, formulated to support liver function and restful sleep.
Pros
- +Vegan capsule shell with no gelatin or animal derivatives
- +Gluten-free and non-GMO formula suits restricted diets
- +Single-ingredient glycine supports targeted supplementation
- +180-count bottle reduces frequency of repurchasing
Cons
- −No third-party certification disclosed on the label
- −Capsule form may be harder to swallow than powder
- −No serving size or dose stated on the label
Key Facts
Detailed Review
Pure Encapsulations Glycine stands out for its single-ingredient focus: just glycine, an amino acid the brand ties to liver function and restful sleep support. The 180-count bottle uses a vegan capsule shell, so it fits gluten-free, non-GMO, and vegetarian routines without extra fillers or common allergens. I see this working best for someone who wants a straightforward amino acid to pair with an existing evening or liver-support regimen.
The main trade-off is transparency: the label does not state a per-serving dose, and no specific third-party certification is named. That makes it harder to compare against glycine products that publish exact milligrams or carry a named seal.
For my money, this suits a shopper who already trusts the Pure Encapsulations name and wants a clean, allergen-free capsule rather than a flavored powder. If precise dosing matters most, I'd look for a label that lists glycine in milligrams per serving.
THORNE Glycine delivers 1 g of the amino acid per serving in 250 capsules, third-party reviewed for label accuracy and contaminant safety.
Pros
- +Third-party reviewed for label accuracy and contaminant safety
- +250-capsule container supports a long daily routine
- +Single-ingredient formula with no unnecessary additives
- +1 g glycine per serving matches common research amounts
Cons
- −Capsule count means multiple pills per 1 g serving
- −No specific certification program named beyond third-party review
- −Capsule format may be harder to swallow than powder
Key Facts
Detailed Review
THORNE Glycine provides 1 gram of glycine per serving in a 250-capsule container, a straightforward single-amino-acid formula rather than a blend. The ingredient list is just glycine, so there is nothing to sort through if you want to isolate this amino acid.
What stands out is the third-party review confirming the label matches the contents and that contaminant levels are within safe limits. That matters for a supplement taken daily, since independent verification is not universal in this category. The 250-capsule size also suits a consistent routine, though it means more than one capsule per 1 g serving.
The main trade-off is the capsule format itself: if you dislike swallowing pills, a powder may be easier. I'd consider this a reasonable pick for someone who wants a plain glycine dose with label verification, but it's worth checking with a healthcare provider before adding any amino acid to a routine, especially if you take other medications.
Why You Should Trust Us
Nutrition Comparison does not run taste tests or ask readers to trust a single reviewer’s sleep diary. We score supplements on what the label actually discloses: ingredient form, dose per serving, capsule count, allergen and dietary flags, and whether the manufacturer publishes third-party testing information. That combination produces the NC Score you see on each product card.
Glycine is a well-studied amino acid, but it is still a supplement, and this article is for informational purposes only. It is not a substitute for medical advice. If you are pregnant, nursing, taking medication, or managing a health condition, talk with a doctor or registered dietitian before adding anything to your routine.
Final Thoughts
What separates a good glycine supplement from a forgettable one comes down to three things: a clearly stated dose per serving, a form your routine can actually accommodate, and a capsule count that does not force you to reorder every few weeks. Everything else is packaging.
For most readers, the NOW Supplements, Glycine 1,000 mg, Free-Form is the best overall choice. The 1,000 mg per capsule dose is easy to work with, whether you take one capsule before bed or split two across the evening, and the vegan capsule and free-form labeling keep the formula simple. If you prefer a larger single dose and do not mind swallowing more capsules at once, the Horbäach Glycine 3000mg Supplement is the budget-conscious pick: it packs 3,000 mg per serving into quick-release capsules at the lowest cost per gram in this group.
If your evening routine already includes magnesium, it is worth understanding how the two minerals and amino acids interact before stacking them. Our breakdown of magnesium glycinate versus citrate explains why the glycinate form is often chosen for nighttime use. And if sleep support is the broader goal, the best teas for insomnia covers non-capsule options that pair well with an amino acid routine.
The right glycine supplement should remove one specific point of confusion: not knowing how much you are actually taking. Once the dose per serving is clear, the rest of the decision gets much easier.
FAQs
Can you take glycine every night?
Glycine is commonly taken nightly as part of a wind-down routine, and most labels list a single 1,000 mg to 3,000 mg serving. Start with the lower end of that range for a week or two to see how your routine responds. If you take prescription medication or have a health condition, check with your doctor first.
Do you need 3,000 mg of glycine per serving?
Higher-dose products are convenient, not necessary. A 1,000 mg capsule gives you more control because you can take one, two, or three depending on the label’s serving guidance. The 3,000 mg formulas simply compress that into fewer capsules, which some people prefer for simplicity.
Is it better to take glycine powder or capsules?
Capsules win on portability and taste, while powder wins on cost per gram and flexibility with dosing. If you already mix a nighttime drink, powder dissolves easily. If you travel or dislike measuring scoops, capsules remove that step entirely. Both deliver the same amino acid.
What is the difference between glycine and magnesium glycinate?
Glycine is a standalone amino acid, while magnesium glycinate binds magnesium to glycine to improve absorption and stomach tolerance. They serve different purposes and can be taken together, though you should count total glycine intake if you use both. Our magnesium supplements for anxiety guide covers the mineral side in more detail.