Jarrow Formulas N-A-G

Supplement Facts

Serving Size: 1 Capsule

Amount Per Serving

%DV

N-Acetyl-D-Glucosamine

700 mg

†

The product is found useful for the following medical conditions

We explored the effects of N-acetyl glucosamine and chondroitin sulfate supplements on knee pain in Japanese adults aged 52 to 87 over 24 weeks. Participants were divided into two groups, one receiving the active supplements and the other a placebo. The results showed a positive impact on knee function and daily physical activity, indicating that longer-term use of these supplements can be beneficial for easing knee pain and improving mobility in older adults.

However, it's important to note that some previous studies have not found such satisfying results about glucosamine and chondroitin effectiveness.

Knee crunch resolved

Most Useful Review

10 people found this helpful

My knee was very crunchy after an injury. I initially took only glucosamine and chondroitin; they did not help. Once I added N-A-G, I finally walked without a crunch in my knee! Those who haven't experienced knee pain will not understand the happiness it brings. The various sources mention the benefits for mucous membranes, but I mainly noticed relief in my knee discomfort.

Updated: Mar 2026

Leg Cramps details

1 people found this helpful

I began taking it on my acupuncturist’s recommendation due to heavy and dull legs. A few days later, I noticed the effects. The size is somewhat large, but one tablet daily is effective, making it hassle-free to use. I am pleased with the quality and the remarkable effect it has had.

Updated: Apr 2025

Liver Disease details

Improved liver function

Most Useful Review

3 people found this helpful

Absolutely fantastic! I periodically purchase NAG for use in complex joint therapy, based on my doctor's recommendation. This is an excellent form of NAG for optimal absorption. Products containing NAG consistently work and assist; I've personally verified this multiple times. Each time, I've noticed improvements with my liver (having had my gallbladder removed), meaning that NAG positively affects my overloaded liver.

Updated: Mar 2026

Tendonitis details

Quick healing benefits

Most Useful Review

2 people found this helpful

I purchased this NAG for my knee, and despite some tummy issues with another product, this one has been fantastic. It works surprisingly quickly! Recently, I fell and sprained my ankle, but I was relieved to have already started taking this, knowing it would expedite my recovery. I had previously used this product successfully for my stomach, which is why I chose it for my knee and now my ankle.

Updated: Apr 2025

Anxiety details

Effective for anxiety

Most Useful Review

This product is excellent for those who suffer from anxiety; it really does alleviate it. However, it causes constipation for me, which is why I rated it four stars.

Updated: Mar 2026

Bloating details

69 people found this helpful

I was diagnosed with Crohn's Disease, which causes extreme pain and bloating. After trying many remedies, Jarrow's NAG and Swanson's Zinc Carnosine have been life-changing. They keep my intestinal discomfort in check, enabling me to function without pharmaceuticals. If I skip it, the pain returns. I plan to take it long-term.

Updated: Mar 2026

Chronic Cough details

Reduces cough severity

Most Useful Review

Following my recovery from COVID, I noticed a significant decrease in my chronic cough after taking this product; it has been quite helpful.

Updated: Apr 2025

Cold Sores details

I often experience inflammation in my joints, particularly my knees, even without exercising. I was recommended NAG for this, and so far, it appears to be beneficial. You can notice the difference over time, and I would suggest it for anyone to take after exercise to assist in relaxing the joints.

Updated: Apr 2025

Flu details

Useful for parents' knee joints. I have repurchased it many times as it is quite effective for the discomfort of knee joint degeneration. I no longer feel uneasy while walking. It also aids in the fluid secretion of the vitreous body of the eye.

Updated: Apr 2025

Multiple Sclerosis details

83 people found this helpful

I drink with multiple sclerosis and have observed its effects on myself. My head has calmed down, and I believe N-acetylglucosamine (NAG) supports the body in restoring myelin membranes—assuming the body has enough building materials. I take LECITHIN alongside NAG and vitamin B6, which aids in myelin construction. If this review was helpful, please let me know. 👍🏼

Updated: Mar 2026

Urinary Tract Infection details

Significant difference

Most Useful Review

2 people found this helpful

I now rely heavily on this product for irritation in my gastrointestinal tract. Taking one daily, it took a few weeks to notice a significant improvement. I have hardly any irritation after about a month of ongoing use.

Updated: Mar 2026

Cold details

4 people found this helpful

Once I started with Glucosamine/Chondroitin, I learned that when I don’t take them during cold or rainy seasons, arthritis pain returns. I've used this brand for about two years, only taking two capsules daily. Until proven otherwise, I will continue as it helps me.

Ulcer details

Remarkable ulcer relief

Most Useful Review

14 people found this helpful

Amazing results for ulcerative colitis and gut issues! After 10 years of mild ulcerative colitis, I had been using probiotics like Visbiome, but it wasn't enough. I started taking this after a six-month flare and, within a week, felt 100% better! I’m so happy to find this product. Just one a day lasts me four months, and alongside taking zinc carnosine, it has been miraculous. I discovered this through another Amazon review and am extremely grateful!

Updated: Apr 2025

Allergies details

Reduced inflammation noted

Most Useful Review

21 people found this helpful

This supplement works well for my allergies and digestive inflammation. With just one capsule twice a day, inflammation has decreased by 75%. I'm cautious due to my shellfish allergy but have had no adverse reactions.

Updated: Mar 2026

Colitis details

14 people found this helpful

Amazing results for ulcerative colitis and gut issues! After ten years of mild ulcerative colitis and various medications, I felt something was missing. After a six-month flare, I started this and within a week, I was back to normal! I'm thrilled to have discovered this, which complements my routine and lasts me four months!

Updated: Apr 2025

Frozen Shoulder details

I take this product three times a day for reducing knee and shoulder joint pain. It appears to be aiding my joint discomfort. I also use Multi Collagen Peptides and Calcium Hydroxyapatite.

Updated: Apr 2025

Gastritis details

Positive healing effects

Most Useful Review

So far, it’s been a great aid in healing my gastritis.

Updated: Apr 2025

Irritable Bowel Syndrome details

Intestinal recovery aid

Most Useful Review

This is very good for maintaining and recovering the intestinal lining.

Updated: Mar 2026

Pelvic Pain details

16 people found this helpful

Pain vanished Since using N-A-G from Jarrow Formulas, the nagging joint and coccyx pain that I had been experiencing for years has largely disappeared.

Updated: Mar 2026

Back Pain details

122 people found this helpful

I have ulcerative colitis and began using this product following some promising studies. My joint pain significantly reduced within a week, allowing me to exercise again. My joints are now functioning at 99%, and I can engage in high-impact workouts without discomfort. My bowel symptoms improved as well, making this product invaluable for my overall health.

Updated: Mar 2026

Arthritis details

SCIENTIFIC SCORE

Questionable

Based on 18 Researches

Potential OA treatment advancements

Serpi M, Bibbo R, Rat S, Roberts H, Hughes C, et al. Novel phosphoramidate prodrugs of N-acetyl-(D)-glucosamine with antidegenerative activity on bovine and human cartilage explants. J Med Chem. 2012;55:4629. doi:10.1021/jm300074y

We explored the potential of N-acetyl-(D)-glucosamine, a compound often used as a dietary supplement for osteoarthritis (OA), to provide effective relief from this chronic joint condition. Our research focused on a series of newly developed prodrugs, specifically targeting ways to enhance the compound's absorption and effectiveness within the body.

We found that some modified versions of N-acetyl-(D)-glucosamine, known as O-3 and O-4 phosphate prodrugs, demonstrated significant chondroprotective effects in vitro. In simple terms, this means they helped protect and support cartilage health, which is vital for those suffering from OA. Notably, the prodrugs that included a specific amino acid called (L)-proline were particularly effective, even outperforming earlier versions.

Overall, our findings suggest that these novel compounds hold promise as new leads in the search for more effective treatments for osteoarthritis. They signify a positive step toward improving the management of this painful and degenerative joint disease.

Effective for osteoarthritis

Most Useful Review

9 people found this helpful

Sodium-free and the most effective I've tried, this product greatly alleviates my osteoarthritis pain and improves my mobility. I switched brands recently, but it was nearly twice the cost and ineffective. Upon returning to this brand, the pain subsided remarkably. Highly recommended.

Updated: Mar 2026

Heart Disease details

SCIENTIFIC SCORE

Moderately Effective

Based on 7 Researches

Excessive -GlcNAcylation effects noted

Umapathi P, Mesubi OO, Banerjee PS, Abrol N, Wang Q, et al. Excessive -GlcNAcylation Causes Heart Failure and Sudden Death. Circulation. 2021;143:1687. doi:10.1161/CIRCULATIONAHA.120.051911

We investigated how levels of -GlcNAcylation, a modification involving N-acetyl glucosamine, relate to heart disease. Using transgenic mouse models, we found that excessive -GlcNAcylation can lead to serious heart issues, including cardiomyopathy and arrhythmias. Interestingly, reducing -GlcNAcylation levels through enhanced OGA activity shows promise in protecting against heart damage, especially under stress conditions. These insights suggest targeting -GlcNAcylation could be a new strategy in heart disease treatment.

Restores sensitivity

Most Useful Review

12 people found this helpful

I purchase this for an adult with multiple sclerosis. Research suggests that this amino acid helps restore nerve connections in experimental models. Given the lack of alternatives aside from symptomatic treatment, we took the plunge. After one month, finger sensitivity improved, speech clarity increased, and overall, there were only positive outcomes. I have ordered another jar.