9 Best Glycine Supplements for Antioxidant Support & Anti-Aging

Did you know that glycine—a simple amino acid—makes up nearly one-third of the amino acids in collagen, the body’s most abundant structural protein? (Fajar et al., 2022) [15].

This little-known fact highlights glycine’s critical role in maintaining the strength and flexibility of our skin, bones, tendons, and ligaments.

But its benefits don’t stop there. Glycine also acts as an inhibitory neurotransmitter in the brain, helping to regulate and stabilize the central nervous system—a function that has made it increasingly popular among those seeking better sleep, stress relief, and overall wellness [5].

As interest in glycine continues to grow, so does the number of supplements on the market. But not all glycine supplements are created equal—especially given that they’re not regulated by the FDA for safety or effectiveness.

To help you make an informed decision, we’ve researched and reviewed the 9 best glycine supplements available today.

Comparison Table of 9 Best Glycine Supplements

How Do We Choose the Best Glycine Supplements?

Purity and Dosage

We prioritize supplements that offer high-purity glycine without unnecessary fillers or additives. An effective serving typically ranges from 2 to 5 grams, depending on your needs. Clear labeling and transparent sourcing are non-negotiable.

Some products today incorporate synergistic compounds to enhance glycine’s effects and bioavailability. One notable combination is Glycine + NAC, which supports detoxification and cellular health. When choosing these formulas, pay attention to the ratio of ingredients to ensure they align with your health goals.

Form and Bioavailability

Glycine is available in several forms—powder, capsules, and tablets. We evaluate each form based on ease of use and absorption. Powders that dissolve quickly and capsules with minimal additives are preferred for their convenience and effectiveness in daily routines.

Manufacturing Standards

We only consider supplements produced in certified facilities that follow Good Manufacturing Practices (GMP) and are tested by third-party laboratories. Certifications from reputable bodies like NSF or production in FDA-registered facilities signal a high level of quality control and safety assurance.

Health Benefits and Effectiveness

The best glycine supplements deliver proven benefits such as improved sleep quality, enhanced cognitive function, joint support, and healthier skin. We take real-user experiences into account to evaluate how well the product performs in practice.

Allergen-Free and Clean Label

Today’s health-conscious consumers demand clean formulations. We prioritize glycine supplements that are non-GMO, vegan, and free from common allergens such as gluten, soy, and dairy. Products with no artificial sweeteners, preservatives, or colorings also receive higher marks.

Brand Reputation and Transparency

We seek out brands that are not only established and trusted but also transparent about their ingredient sourcing, formulation, and testing protocols.

Reputable companies often publish third-party test results and are endorsed by health professionals or wellness influencers. A brand’s willingness to disclose full product information without hiding behind vague marketing is a key sign of integrity.

Value for Money

We assess not just the bottle price, but the cost per serving—a more accurate indicator of real value. Most quality glycine supplements fall between $0.30 to $0.70 per serving, depending on dosage, formulation, and ingredient quality.

We also consider quantity per bottle and whether it includes premium features like synergistic compounds or clinically backed ingredients to determine true cost-effectiveness.

9 Best Glycine Supplements for Antioxidant Support & Anti-Aging

Vinatura GLYNAC Supplement 1000MG - 45 Servings | $25.89

Review

Vinatura GLYNAC Supplement 1000MG is an Amazon’s Choice product that has earned recognition for its quality and value. Designed to support healthy aging and cellular vitality, each serving delivers 1000mg of a powerful combination of 600mg N-Acetylcysteine (NAC) and 400mg Glycine.

These two amino acids play a critical role in replenishing glutathione—an essential antioxidant in the body—and promoting overall cellular health and protein synthesis.

A study published on PubMed examining the effects of supplementing Glycine and N-Acetylcysteine (GlyNAC) in older adults reported significant improvements in multiple age-related abnormalities. Over a 16-week period, GlyNAC supplementation was shown to help reverse key markers of aging and enhance overall health in elderly individuals (Kumar et al., 2022) [1].

This research has contributed to growing interest in products like Viantura GlyNAC 1000mg, particularly among middle-aged and older adults who are seeking proactive solutions to support healthy aging.

Many users report noticeable improvements in energy, recovery, and overall well-being.

As one satisfied customer, Tatiana, puts it: “I’ve been using VINATURA GLYNAC Supplement (Glycine & NAC) and really feel the benefits—better energy, recovery, and overall well-being. The NAC has a strong sulfur smell, which is totally normal and actually a sign of good quality!”*

The supplement is also designed with clean-label attributes that align with modern consumer needs. It is non-GMO, vegan, gluten-free, dairy-free, and sugar-free, and is manufactured under cGMP standards with third-party testing.

Over 84% of users express satisfaction, praising the quality and the energy-boosting effects. However, it's worth noting that some individuals may be sensitive to the naturally strong scent of NAC, which may affect taste perception.*

Pros

• Scientifically backed blend of Glycine and NAC for optimal cellular health.
  1000mg per serving with a balanced ratio of 600mg NAC and 400mg Glycine.
• Non-GMO, vegan, gluten-free, dairy-free, and sugar-free.
• Manufactured in a cGMP-certified facility and third-party tested.
• Recognized as Amazon’s Choice for its value and customer satisfaction.
• Highly rated for improving energy, recovery, and overall vitality.

Cons

• NAC has a naturally strong sulfur odor that some users may find unpleasant.
• Taste may not be suitable for all palates, depending on individual sensitivity.

Horbäach Glycine 3000mg 33 Capsules | $9.99

Horbäach Glycine 3000mg is a focused, single-ingredient supplement ideal for those specifically seeking high-potency Glycine. Earning the Amazon’s Choice badge and with over 1,000 purchases monthly, this product appeals to consumers looking for effective support in sleep quality, joint health, and overall well-being.

Each serving delivers 3000mg of therapeutic-grade Glycine, delivered via three quick-release capsules—equivalent to about a one-month supply.

This supplement is well-regarded for its purity and clean formulation. It’s free from common allergens including gluten, soy, milk, and lactose, and contains no artificial ingredients. It's also non-GMO, made in the USA under GMP standards, and third-party tested for safety and quality.

With up to 87% of customers expressing satisfaction, users report better sleep, enhanced joint mobility, and even a rejuvenated feeling, with one reviewer sharing they "feel younger at 60."*

However, the product’s front labeling has caused confusion for some customers. The “3000mg” displayed prominently may mislead consumers into thinking each capsule contains 3000mg, whereas the actual dose per capsule is 1000mg, requiring three capsules per serving.*

One reviewer, FiguringStuffOut, commented, “By putting 3,000 front and center you would think that this has 3,000 IU per capsule. That is not true... It's misleading.” While the value and quality are solid, this aspect has led to concerns about transparency and perceived cost-effectiveness.*

Pros

• Delivers 3000mg of therapeutic-grade Glycine per serving.
• Focused single-ingredient formula ideal for Glycine-only supplementation.
• Quick-release capsules for fast absorption.
• Allergen-friendly: gluten-free, soy-free, lactose-free, and non-GMO.
• Manufactured in the USA under GMP standards with third-party testing.
• Amazon’s Choice product with strong customer satisfaction.

Cons

• Labeling may mislead consumers into thinking 3000mg is per capsule, not per serving.
• Requires 3 capsules per serving, which may be inconvenient for some users.
  Some users reported no noticeable effects.

Vital Nutrient Glycine Powder 4000mg - 62 Servings | $34.90

The next contender on this list is a powder-form glycine supplement, ideal for those who prefer mixing their supplements into beverages for convenient daily use.

Each serving provides a generous 4000mg (4g) of pure Glycine, with 62 servings per container—making it a long-lasting and cost-effective option for individuals looking to support sleep, cognitive health, detoxification, and antioxidant defenses.

This product is produced in an NSF-certified facility in Middletown, CT and comes from a brand with over 30 years of practitioner-driven history.

Vital Nutrients is known for its commitment to clinically relevant, clean-label formulas trusted by health professionals and wellness enthusiasts alike. The powder format makes it easy to mix into beverages, which many users find convenient and customizable for their routines.

Receiving the Amazon’s Choice badge and more than 400 monthly purchases, Vital Nutrient Glycine Powder garners positive feedback from over 90% of users. Customers report improved sleep quality—many noting they sleep through the night and wake up feeling refreshed.*

Others highlight the product’s calming effects, value for money, and pleasant taste. One user shared that the supplement "quiets their mind," contributing to better rest and relaxation.*

Despite overwhelmingly positive reviews, a small minority have noted quality concerns, such as the appearance of brown flecks in newer containers.* Additionally, as a powder supplement, it may not be suitable for those who prefer the convenience of capsules and dislike mixing their supplements into drinks.

Pros

• Delivers 4000mg of Glycine per serving—highest potency among the options.
• Powder format allows flexible dosing and easy mixing into beverages.
• Clean-label formula: free from gluten, dairy, nuts, eggs, sugar, artificial colors and sweeteners.
• Produced in an NSF-certified facility with over 30 years of brand credibility.
• Highly rated with over 90% positive feedback and minimal negative reviews.
• Supports sleep, cognition, detox, and antioxidant defenses effectively.

Cons

• Powder form may be less convenient for those who prefer capsules.
• Minor quality complaints (e.g., brown flecks in some containers).
• Slightly higher price point compared to capsule-based alternatives.

Pure Encapsulations Glycine 180's 1500mg - 60 Servings | $32.60

Pure Encapsulations Glycine offers 1500mg of free-form Glycine per serving, across 60 servings per bottle. As a capsule-based formula, it is ideal for users who prioritize convenience and clean, clinically-backed formulations.

The brand has built a strong reputation for purity, and this product is no exception—certified gluten-free by GFCO.org and free from GMOs, soy, dairy, artificial additives, and unnecessary fillers like magnesium stearate or hydrogenated oils.

What sets this supplement apart is not only its formulation but also the brand's environmental commitment.

Pure Encapsulations actively reduces plastic consumption by eliminating unnecessary packaging such as bottle neckbands, and they partner with TerraCycle to offer recycling options for materials not accepted in curbside programs. These sustainability efforts resonate strongly with eco-conscious consumers.

The supplement holds the Amazon’s Choice badge, backed by over 2,000 monthly purchases and a 92% positive rating. Users consistently praise its effectiveness in promoting restful sleep, reducing stress, and aiding detoxification.*

One enthusiastic user, T & T Vero, shared: “I am dreaming for the first time in years! I take a total of 3 as per the instructions in between meals… it really did change my life!” Such feedback illustrates the product’s impact, especially for those dealing with long-standing sleep challenges or chronic stress.*

However, as with many supplements, individual responses may vary. A small number of users have reported digestive issues such as diarrhea.* While these cases are rare, they highlight the importance of starting with a lower dose and observing one’s own tolerance.

Pros

• 1500mg of free-form Glycine per serving in easy-to-swallow capsules.
  
• Certified gluten-free; free from GMO, soy, dairy, artificial additives, trans fats, and unnecessary fillers.
• Strong brand commitment to sustainability and eco-friendly packaging.
• Clinically backed benefits for stress relief, improved sleep, and detoxification.
• Amazon’s Choice product with high customer satisfaction (92% positive reviews).
• Trusted by health professionals and widely used for wellness support.
  

Cons

• Some users report digestive discomfort, including diarrhea.*
• Slightly higher price point relative to some Glycine-only alternatives.
• Effects may vary depending on individual tolerance and health needs.

Best Naturals Glycine Supplement 1000 Mg - 180 servings | $14.99

Best Naturals Glycine Supplement delivers a straightforward, cost-effective approach to Glycine supplementation. With 1000mg per serving and 180 capsules per bottle, it offers a generous supply ideal for long-term use.

This product focuses on supporting energy production and improving sleep quality, while maintaining a clean-label profile that appeals to health-conscious consumers.

Manufactured in a GMP-compliant, FDA-registered facility in the USA, the supplement is also third-party lab tested for purity and quality. It’s free from artificial colors, flavors, sweeteners, and common allergens including gluten, egg, lactose, and yeast.

The capsule includes minimal excipients such as magnesium stearate (vegetable source), silicon dioxide, and maltodextrin.

Customers appreciate the supplement’s affordability and effectiveness—many report falling asleep within 30 minutes of taking it and waking up feeling refreshed. Its simplicity and price point make it a popular choice, with over 100 purchases monthly and 82% of users leaving positive feedback.*

Despite its benefits, some users find the capsule size too large, making it difficult to swallow. Additionally, there have been occasional complaints about product packaging not being sturdy or secure during shipment. While these are not widespread issues, they are worth considering for those sensitive to capsule size or relying on secure packaging for online orders.*

Pros

• 1000mg Glycine per capsule with 180 servings per bottle—great value.
• Free from gluten, sugar, artificial additives, and common allergens.
• Manufactured in the USA in a GMP-compliant, FDA-registered facility.
• Third-party lab tested for purity and quality.
• Supports sleep and energy production effectively.
• Affordable price point and well-suited for daily long-term use.

Cons

• Capsules are large, which may be difficult for some users to swallow.
• Some packaging issues reported during shipping.
• Slightly lower satisfaction rate compared to higher-end Glycine products.

NOW Foods Supplements, Glycine 1,000 mg - 33 serrvings | $9.97

NOW Foods Glycine 1,000 mg is a widely recognized and trusted supplement from a longstanding family-owned company, with manufacturing roots dating back to 1968. With over 8,000 monthly purchases and more than 4,700 global reviews, this product has rightfully earned the Amazon’s Choice badge in its category.

Each serving provides 3,000mg of free-form Glycine, delivered through three capsules per serving, with a total of 33 servings per bottle—approximately a one-month supply.

It's formulated to support restful sleep and nervous system function, making it a practical choice for individuals looking to ease into glycine supplementation or address stress-related concerns.

NOW’s commitment to quality is evident through its Intertek GMP certification and U.S.-based packaging. Users consistently report enhanced sleep quality, improved muscle recovery, and increased glutathione levels. The product is also praised for offering solid value at a reasonable price, with minimal side effects reported in the majority of cases.

However, some customers experience gastrointestinal discomfort such as nausea or stomach pain, and a few users mention that it did not deliver noticeable effects for them. Another common concern is the capsule size—described by several as too large to swallow comfortably.*

Pros

• 3,000mg of free-form Glycine per serving.
  
• Trusted brand with long-standing manufacturing history (since 1968).
• Intertek GMP certified and packaged in the USA.
• Supports restful sleep, muscle recovery, and nervous system health.
• Amazon’s Choice with strong customer satisfaction (89% positive reviews).
• Affordable and accessible for beginners.

Cons

• Requires taking 3 large capsules per serving—may be difficult for some users.
• Reports of mild side effects like stomach discomfort and nausea.
• May not work for all users; results can vary.
  

Life Extension Glycine, 1000 mg - 100 servings | $12.00

Life Extension Glycine is a sleep-supporting amino acid supplement developed by a trusted brand with over 40 years of scientific research and formulation expertise.

Each capsule contains 1000mg of Glycine, and with 100 capsules per bottle, it offers a solid supply for regular users. Manufactured in the USA with non-GMO and gluten-free standards, this vegetarian-friendly supplement is geared toward individuals seeking a clean, high-quality solution for better rest and relaxation.

With more than 5,000 monthly purchases and 2,500+ global reviews averaging 4.6 stars, this product has become a top-tier choice for those prioritizing sleep quality. The brand emphasizes the use of the finest raw ingredients and provides a Certificate of Analysis for transparency—an added layer of trust appreciated by health-conscious users.

A large majority of users—around 90%—report being highly satisfied with the product, noting noticeable improvements in sleep quality and relaxation. One verified customer, Cade Joiner, emphasized its effectiveness, stating that it had a greater impact than any other supplement he had tried and expressing a strong recommendation for those seeking better rest.*

Despite the widespread praise, some users have reported mild side effects related to gut health, prostate, or urinary issues. Others have commented on the product’s taste, which may be unpleasant for a few, even in capsule form.*

While these experiences are not common, they serve as important considerations when evaluating supplement suitability on an individual basis.*

Pros

• 1000mg Glycine per capsule with 100 servings per bottle.
• Developed by a brand with 40+ years of research-backed reputation.
• Non-GMO, gluten-free, vegetarian formula.
• Manufactured in the USA with a Certificate of Analysis available.
• Highly rated (4.6 stars) with strong user satisfaction (90% positive feedback).
• Proven support for sleep quality and relaxation.

Cons

• Some users report mild side effects related to gut and urinary health.
• Unpleasant taste noted by a few customers.
• Effects may vary depending on individual health conditions.

THORNE Glycine - 125 servings | $29.00

THORNE Glycine is a high-quality amino acid supplement developed by one of the most trusted names in the health and wellness industry.

Known for partnerships with over 45,000 health professionals, 100+ sports teams, and institutions like the Mayo Clinic, THORNE has earned a reputation for clinical-grade quality. Each serving delivers 1000mg of Glycine, designed to support muscle function, detoxification, and relaxation—making it especially appealing for fitness enthusiasts and athletes.

This supplement has gained significant popularity, with more than 3,000 monthly purchases and over 1,000 global reviews. With an 89% positive feedback rate, customers frequently highlight its effectiveness in improving sleep, enhancing energy, and aiding post-exercise recovery.*

Many appreciate the clean-label formula, which is gluten-free, dairy-free, soy-free, and free from artificial flavors. Users also find the capsules easy to swallow and mention the product has a neutral to pleasant taste—something that sets it apart in the amino acid category.*

While widely praised, the supplement has received mixed feedback on its sleep-related effects. Some users report improved rest and feeling more refreshed in the morning, but others experienced sleep disturbances after taking it. These divergent reactions underscore the importance of personal body chemistry when it comes to amino acid supplementation.*

Pros

• 1000mg Glycine per serving—ideal for muscle support and relaxation.
• From a highly reputable brand trusted by professionals and elite athletes.
• Clean-label: gluten-free, dairy-free, soy-free, and no artificial flavors.
• Effective for detox, muscle recovery, and improved sleep for many users.
• Pleasant taste and easy-to-swallow capsules.
• Modern packaging and consistent quality assurance.

Cons

• Mixed user responses regarding sleep—may disturb sleep in some cases.
• Slightly premium-priced compared to standard glycine supplements.
  
• Effects may vary depending on personal tolerance and usage timing.

Nutricost Glycine Powder 1lb -  151 servings | $21.95

Nutricost Glycine Powder is a high-value, unflavored supplement that offers a generous 3000mg of Glycine per scoop, with 151 servings per container—enough for approximately five months of daily use.

As an Amazon’s Choice product with over 2,000 monthly purchases, it stands out for its simplicity, effectiveness, and cost-efficiency. The powder dissolves easily in liquids, making it an excellent choice for those who prefer mixing their supplements into beverages like coffee or water.

Certified non-GMO, gluten-free, and manufactured in a GMP-compliant, third-party tested facility, the product delivers clean and reliable support for sleep improvement and relaxation. Customers consistently praise its subtle sweetness, ease of use, and effectiveness.

One enthusiastic user mentioned incorporating the supplement into their daily routine, noting its neutral taste with a slight sweetness. They found it easy to mix into coffee in the morning and reported that taking it before bed helped improve their sleep quality.*

With 92% of users rating it 4 or 5 stars, most reviews are highly positive. However, there are a few concerns regarding product packaging and quality control. Some customers reported torn seals upon delivery, and in rare cases, foreign contamination like hair found in the powder. These incidents have led to questions about manufacturing consistency, though they remain a small portion of the overall feedback.*

Pros

• 3000mg of Glycine per serving with a large 151-serving container.
• Unflavored powder with a slight natural sweetness—easy to mix into drinks.
• Non-GMO, gluten-free, GMP-compliant, and third-party tested.
• Excellent value for money with a long-lasting 5-month supply.
• Highly rated (92% 4–5 stars) for sleep support and relaxation.
• Amazon’s Choice product with strong monthly sales.

Cons

• Some reports of poor packaging (e.g., broken seals).
• Rare incidents of product contamination (e.g., foreign objects in powder).
• Powder format may not suit users who prefer capsules or ready-to-take forms.

Conclusion

In summary, glycine is an essential amino acid that supports a range of critical health functions, including sleep quality, neurological health, and muscle recovery. Choosing the right glycine supplement can significantly enhance its benefits and overall effectiveness. Reputable brands such as Vinatura Supplements, Horbäach, Pure Encapsulations, and NOW Foods offer high-quality products tailored to diverse needs and preferences. Selecting a supplement that aligns with your lifestyle and wellness goals can help you experience noticeable improvements in your daily health and well-being.