AOD 9604 vs. Fragment 171-196: Fat-Burning Peptides Explained

Here’s everything you need to know before you try AOD 9604 and Fragment 171-196. I did a deep dive into these two fat burning peptides so you don’t have to. Read below to learn about their differences, benefits and potential risks and to see if one is right for you.

Disclaimer: This blog is for informational purposes only and is not intended to provide medical advice. Always consult your healthcare provider before starting any new supplement or injectable therapy.

What Are AOD 9604 and Fragment 171-196?

Let’s start with the basics. AOD 9604 and Fragment 171-196 are synthetic (made in a lab) peptides derived from a small portion of the human growth hormone (HGH) molecule. Both were developed with one primary goal in mind: fat loss—without the full-body effects or side effects of traditional HGH therapy.

Here’s the science in a nutshell:

• HGH is a 191-amino acid chain that plays a key role in growth, metabolism, muscle repair, and fat burning.
• Fragment 171-196 and AOD 9604 are shortened versions of this chain that mimic HGH’s fat-burning properties without stimulating growth.

These peptides were designed to target fat by increasing its breakdown while minimizing unwanted side effects associated with HGH, like insulin resistance or excessive muscle growth.

Related Read: THE POTENTIAL OF EPITALON: A COMPREHENSIVE GUIDE TO THIS GROUNDBREAKING PEPTIDE

AOD 9604: The Anti-Obesity Peptide

AOD stands for “Advanced Obesity Drug,” and scientists in Australia originally developed it to combat obesity in a way that was safer than traditional growth hormone therapy.

How It Works:

AOD 9604 is made up of the last 15 amino acids of HGH (positions 177–191), that enhances its fat-burning activity without anabolic effects. It is essentially the same peptide as Frag 176-191, except that scientists replaced the last amino acid in AOD’s chain with L-Tyrosine.

It works by:

• Stimulating the breakdown of stored fat
• Inhibiting the formation of new fat
• Boosting metabolism (without increasing blood sugar or muscle mass)

Unlike HGH, studies show that AOD 9604 does not affect blood glucose levels or IGF-1 (insulin growth factor), which makes it appealing to people worried about insulin resistance or long-term hormone imbalances.

Fragment 171-196: The Fat-Burning Clone of HGH

This peptide, often referred to as Frag 176-191, is a synthetic piece of HGH designed to amplify the fat-burning effects without influencing growth or insulin levels.

How It Works:

Fragment 171-196 stimulates fat breakdown and inhibits fat storage, especially in stubborn areas like:

• Belly fat
• Thighs
• Love handles

It’s shown promising results in reducing visceral fat while preserving lean muscle mass, which is why it’s popular among athletes, biohackers, and those working through weight loss plateaus.

Key Differences Between AOD 9604 and Frag 171-196

• Derived from: HGH (176–191)
• Purpose: Fat loss; performance enhancement
• Clinical history: Limited human studies
• Legal Status: Research chemical only
• Muscle growth: No
• Insulin impact: None 
• Fat loss: Yes

Related Read: TOP 6 INJECTABLE PEPTIDES FOR MITOCHONDRIAL HEALTH AND LONGEVITY

Dosage and Administration

Both peptides are typically administered via subcutaneous injection—usually in the stomach area or thighs for targeted fat burning.

⚖️ Recommended Dosages:

AOD 9604: 250-300 mcg once or twice a day

Frag 171-196: 250–500 mcg once daily (AM fasted)

⏰ Best Times to Inject:

• On an empty stomach (at least 1 hour before or after eating)
• First thing in the morning
• Pre-workout or post-workout for best fat metabolism

Make sure to rotate injection sites to prevent irritation.

Results: What to Expect

Let’s be honest—these aren’t miracle drugs. You still have to eat clean, move daily, and stay consistent. But when used correctly, users report:

AOD 9604:

• Gradual, consistent fat loss (especially around the midsection)
• Improved recovery after workouts
• Enhanced metabolism

Frag 171-196:

• Faster results with fat-burning
• Improved energy and performance
• Visible difference in body composition within 4–6 weeks

💡 Pro Tip: Both peptides work best when combined with intermittent fasting, a low-carb diet, or fasted cardio.

Do They Raise Blood Pressure, Insulin, or Triglycerides?

Blood Pressure:

• Both AOD 9604 and Frag 171-196 are not known to raise blood pressure.
• They do not stimulate systemic HGH or IGF-1, so the cardiovascular side effects seen with full HGH are avoided.

Insulin or Blood Sugar:

• Neither peptide increases insulin or blood glucose.
• AOD 9604 has been studied in obese individuals with metabolic syndrome and did not worsen insulin resistance.

Triglycerides:

• No studies show a direct increase in triglycerides.
• Some data suggest that improvements in fat metabolism support healthier lipid levels over time.

Have These Peptides Been Studied in Humans?

✅ AOD 9604:

• Yes! It has undergone human clinical trials in Australia.
• Studied for obesity treatment, fat metabolism, and safety.
• Results: Well-tolerated, no impact on IGF-1, blood sugar, or insulin.
• It has been classified as GRAS (Generally Recognized As Safe) in the U.S.

⚠️ Fragment 171-196:

• Human research is limited.
• Most studies are in animals or lab settings.
• Widely used anecdotally in fitness and performance spaces, but lacks clinical trials.

Risks and Considerations

While side effects are minimal, there are still risks to consider:

• Product purity – Always get peptides from a reputable compounding pharmacy or research lab.
• Storage – Keep reconstituted peptides in the fridge and use within 30 days.
• Overuse – More is not better. Stick to recommended doses and cycle on/off to prevent tolerance.
• Legal status – Laws vary. In some countries, peptides like Frag 171-196 are legal for personal research use; in others, they may be restricted.

How to Make Them Work Best

If you’re going to invest in peptides, make them count. Here are tips to get the most bang for your buck:

1. Clean Up Your Diet – Focus on whole foods, lean proteins, and fewer processed carbs.
2. Incorporate Fasted Workouts – A morning walk, strength training, or Pilates on an empty stomach can amplify fat loss.
3. Stay Hydrated – Peptides metabolize best when you’re well-hydrated.
4. Sleep – HGH and peptide function is tied to circadian rhythm. Aim for 7–9 hours of quality sleep.
5. Track Progress – Take weekly pics, measure waist circumference, or use a smart scale to monitor changes.

Which One Is Better?

It depends on your goals.

• Choose AOD 9604 for a gentle, sustained fat-loss peptide with a more favorable safety profile. It is great for beginners or those looking to reduce stubborn fat without dramatic effects.
• Go with Fragment 171-196 if you’re serious about visible, faster fat reduction, especially if you’re already active or hitting a weight loss plateau.

💥 Some people stack both together for synergistic results but always consult with a provider before combining therapies.

Where to Get Them

Be selective about your source if you’re considering trying peptides like AOD 9604 or Frag 171-196 because quality can vary greatly.

Look for:

• Compounding pharmacies with a medical provider overseeing prescriptions
• Third-party testing for purity and potency
• Transparency in sourcing and manufacturing

A functional medicine provider, biohacking clinic, or weight loss specialist may legally and responsibly offer these peptides.

👉 There are many places to purchase peptides online. As previously stated, do your research before buying peptides. Here’s a list of online suppliers; however, I am not affiliated with any of these sites or recommending any of them. Make sure to do your due diligence and read their company information, reviews, disclaimers, and Certificates of Authenticities (COAs). Be sure to look for high purity, good reviews, and clear labeling. Here’s a short list to check out:  

Peptide Pros

Peptide Sciences

Polaris Peptides

Limitless Life Nootropics

AC Peptides I personally have ordered from this site. I am not an affiliate nor recommending, however they have offered me a referral link to save 10% on peptides.

It’s always best to find a health practitioner who will guide you in making the right decisions based on your medical history about which peptides are best for you. 

Kelly’s Thoughts

Peptides like AOD 9604 and Fragment 171-196 are exciting tools in the health and longevity space, especially for people who are already living a healthy lifestyle but want to accelerate their results.

Peptides are not magic pills (or shots), but when used correctly, they can support fat loss in a safe and targeted way. Always pair peptides with nutrition, movement, hydration, and rest for optimal results.

And remember—this isn’t medical advice. It’s just good ol’ info from someone who’s passionate about wellness, longevity, and feeling your best.

DISCLAIMER: THIS IS NOT MEDICAL ADVICE. IT IS FOR INFORMATIONAL PURPOSES ONLY. FOR THE FULL PRIVACY POLICY, CLICK HERE. 

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References:

1. Ng FM, et al. “The effect of AOD9604 on body weight and fat mass in overweight and obese adults: a randomized controlled trial.” J Endocrinol Metab. 2006.
2. Heffernan M, et al. “AOD9604 – a lipolytic peptide derived from human growth hormone: efficacy and safety studies.” Obesity Research & Clinical Practice. 2010.
3. Wu Z, et al. “GH fragment 176-191 stimulates lipolysis in adipocytes via beta-adrenergic pathways.” J Mol Endocrinol. 2009.
4. https://www.corepeptides.com/fragment-176-191-peptide-and-studies-in-weight/
5. Li L, et al. “Pharmacological profile of a human growth hormone fragment (hGH 177-191) in obese Zucker rats.” Neuropeptides. 2000.
6. FDA GRAS Notice No. GRN 000638. AOD9604. U.S. Food & Drug Administration.