What is MK-677? | What You MUST Know

Dr. Mike Jansen

Last Updated December 17, 2022

Dr. Mike Jansen

 December 17, 2022

Curious… what is MK-677?

Have you been wondering about what benefits this supplement has, or what an optimal dose of MK-677 looks like?

Then you’ve come to the right place. In this comprehensive guide, we detail everything you need to know about MK-677, including exactly what this over-the-counter supplement is, and why it’s helpful for both bodybuilders and those recovering from illnesses or injuries.

We also answer your most important questions, including:

  • Is MK-677 a steroid?
  • Do I have to cycle MK-677?
  • What are the side effects of MK-677?

…And much more!

In this article, we put together a detailed collection of facts about MK-677 and how it has been applied in the world of medicine.

We also explore how people use it, and more importantly, why you should consider buying it soon in order to conduct your own research.

Now let’s get started!

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What is MK-677?

MK-677, also known as Ibutamoren, Nutrabol, and MK-0677, was first patented in 1995. It was originally developed to help individuals suffering from growth hormone deficiency, as well as muscle catabolism and bone frailty in the elderly [1].

MK-677 solves this problem in a unique manner because it is a growth hormone secretagogue.

Essentially, instead of having to inject exogenous growth hormone, MK-677 stimulates the pituitary gland to release growth hormone naturally.

MK-677 is often erroneously lumped into the same category as SARMs, or selective androgen receptor modulators. This class of substances was developed to replace steroids in the medical industry.

Researchers were under the impression they would provide the muscle building effects of anabolic steroids without as many harmful side effects.

MK-677 Vs Sarms

To be clear, MK-677 is not a SARM. MK-677 is a growth hormone (GH) releasing peptide-mimetic [2].

In other words, MK-677 will stimulate the pituitary gland to produce more growth hormone, which in turn would also increase the amount of Insulin Growth like Factor (IGF-1) in the body. Researches has found substances like these to be beneficial for patients suffering from muscle wastage or a growth hormone deficiency [2].

MK-677 is technically a non-peptide agonist of the Ghrelin Receptor, increasing somatotrophe secretion of GH [3].

This means that MK-677 can increase the amount of growth hormone the pituitary gland secretes, which in turn will also increase IGF-1 levels within the body.

Increased levels of GH and IGF can aid in muscle growth as well as fat loss [4].

MK-677 And Growth Hormone

Another benefit of MK-677 over other secretagogues is the ability to raise GH levels without raising cortisol levels, allowing for greater increase in fat free mass.

Growth hormone secretagogues like MK-677 enhance the pulsatile release of growth hormone in the anterior pituitary gland, resulting in sustained elevation of insulin-like growth factor (IGF)-I levels.

Growth hormone is a large peptide molecule, so it typically needs to be injected into subcutaneous tissue or muscle to get it into the blood. However, since MK-677 is an orally active non-peptide mimic of GHSs, it can stimulate the release of growth hormone effectively by intravenous, subcutaneous, intraperitoneal, and oral administration [5].


What are the Benefits of MK-677?

Over the past few years, talk about the benefits of taking MK-677 has swept through the bodybuilding and fitness community, due to the fact that it’s often referred to as ‘legal growth hormone’.

But could it be that this substance is being overhyped?

Could this be just another short-lived trend in the supplement industry?

Or, can MK-677 actually produce the same, or even greater muscle-building benefits than often seen with human growth hormone (HGH)?

Here are some of the biggest benefits of MK-677:

  • Lean muscle mass gains
  • Decreased body fat levels
  • Faster recovery from workouts
  • Enhanced sleep

Lean Muscle Mass Gains

Of the many benefits that can come from taking MK-677, one of the most noticeable is improvements in both lean muscle mass and strength [1].

Part of the reason why this happens is because MK-677 is a growth hormone secretagogue. This means it causes the body to produce more growth hormone and thus increase muscular size.

More specifically, a number of studies have shown MK-677 can increase IGF-1 levels by between 39-89% [6].

One study in particular found that healthy elderly subjects who took MK-677 experienced a sustained increase in the amplitude of GH and IGF-I pulsatile secretion to levels observed in young adults.

This increase in muscle mass also comes about due to the fact that MK-677 can lead to an increased appetite.

It’s perfect if you’re trying to bulk up, as it will allow you to stomach much more calories than you would otherwise be able to [7].

Decreased Body Fat Levels

Burning body fat is another prominent benefit that MK-677 can confer due to an increase in basal metabolic rate.

One study involving 24 obese males were treated with MK-677 25 mg or placebo daily for 8 weeks.

The results of this trial indicated changes in body composition and energy expenditure of an anabolic nature, with a sustained increase in fat-free mass [8].

Faster Recovery From Workouts

In addition, MK-677 is also well-known for its healing and therapeutic benefits – not just for building muscle.

This growth hormone secretagogue has been effectively used in several cases to help medical patients recover from injuries and increase bone muscle density, such as in one randomized, double-blind study that looked at 123 elderly hip fracture patients receiving 25mg/day of MK-677 or placebo [6].

After 24 weeks had passed, the group of participants dosing MK-677 were able to walk upstairs at a faster pace compared to the placebo, with their gait speed also increasing.

In addition, the MK-677 group experienced fewer falls during the study compared to the placebo. On top of that, IGF-1 levels in treated patients increased by 51.4 ng/mL compared to placebo.

In conclusion, it was found that a daily dose of MK-677 stimulates bone turnover in the elderly based on elevations in biochemical markers of bone resorption and formation [6].

Enhanced Sleep

Proper MK-677 usage has also been associated with improved sleep, as evidenced in one double-blind, placebo-controlled study involving 8 subjects between the ages of 18-30. Doses were 5 and 25 milligrams of MK-677 and matching placebo.

The high-dose MK-677 treatment resulted in an approximately 50% increase in the duration of stage IV and in a more than 20% increase in REM sleep as compared to placebo.

They also found that interruptions to normal sleep decreased from 42% under placebo to 8% under high-dose MK-677.

Essentially, not only did subjects experience a much deeper, more restful sleep, but they also remained in those deep states of sleep for longer periods without interruptions. Ultimately, improved sleep has a multitude of benefits for overall health and well-being, in addition to helping build muscle more effectively [9].

Is MK-677 Safe?

The choice to start taking any sort of bodybuilding supplement often comes with many factors to consider.

Firstly, does it actually produce the benefits it promises to? And secondly, how safe is this supplement?

In order to illustrate MK-677’s risk profile more clearly, we’ll first draw a comparison with anabolic steroids. Even responsible use of anabolic steroids can present the risk of adverse side effects, depending on what kind of steroid is used, for how long, and what the dosage is.

Irritability, or an increased appetite are some of the less harmful effects.

Skin rashes, shrinking of the gonads, high blood pressure, and gynecomastia are some of the more severe effects that users may experience [10].

Since MK-677 is a growth hormone secretagogue, it would also make sense to point out that consuming pure human growth hormone also carries some risks with it.

Adverse side effects reported as the result of injecting human growth hormone can include carpal tunnel syndrome, growth of cancerous tumors, and hyperglycemia [11].

In comparison, studies conducted on MK-677 have shown that side effects tend to be minor at the very worst. In fact, we can reference one study conducted recently in 2020. Ibutamoren (MK-677) use was examined for 6 months in 161 elderly patients recovering from hip fracture. No adverse effects were observed in any of the participants [6].

To limit and prevent unwanted side effects, it’s advised that research subjects perform no more than 1-2 cycles per year, and to not exceed 50 mg per day during the study.


Is MK-677 Legal?

Taking into account the exciting claims made about MK-677, such as it being labeled ‘legal growth hormone’, it’s understandable that some might be confused about whether or not MK-677 is totally legal.

As of early 2023, when this article was written, MK-677 is completely legal and available to buy as an over-the-counter supplement.

This is a crucial difference to take into account between MK-677 and steroids, as well as SARMs.

As mentioned in this guide, MK-677 is not classified as an anabolic steroid nor a SARM, and is therefore completely legal to purchase, possess, or consume in the United States and most other countries [10].

There are no ‘loopholes’ being exploited here, either.

This is often the case with SARMs, which can be purchased online and used legally under the guise that they are for ‘research purposes.’ MK-677 isn’t a SARM and doesn’t pose any of the risks associated with them, so there’s no need for manufacturers to label MK-677 supplements as ‘not for human consumption’ and only for ‘research purposes’.

As such, there’s no need to worry that a nosy customs agent might seize your order of MK-677 because they suspect the product isn’t going to be used properly, according to the law.

Is MK-677 a Banned Substance?

While MK-677 isn’t listed as a Controlled Drug in a number of countries, such as Canada and the United States, it’s a different story when it comes to professional sports.

The governing body responsible for deciding which substances can be allowed to be consumed in professional competitive sports, the World Anti-Doping Agency (WADA), has banned MK-677 and placed it under category S2 of prohibited substances.

This means that athletes competing at the highest levels of sport, such as the Olympics or the IFBB, are not permitted to have MK-677 in their system when competing [12].

This is most likely due to the fact that MK-677 is a growth hormone secretagogue, and thus causes the body to release more growth hormone and grow at an accelerated pace, which goes against the spirit of fair play and can be considered an unfair advantage.


MK-677 and Bodybuilding

In bodybuilding, substances like MK-677 are looked at as a convenient alternative to traditional anabolic steroids, pro-hormones, or SARMS, as it has an especially low risk profile.

MK-677 is currently available in capsules and liquid form, which makes it easy to take with food or mixed into a beverage.

Despite limited exceptions, such as the oral steroid dianabol, using a syringe for taking these compounds is usually a point of consternation for athletes who want to take their physiques to the next level, hence why they opt for less invasive performance-enhancing substances, such as MK-677.

When it comes to how MK-677 ought to be dosed, the data available from various studies has shown that an optimal daily dose would be around 25 milligrams, as this is the dose most often studied in randomized controlled trials.

The studies referenced in this article have mainly focused on MK-677 cycles between 8-12 weeks, with very few serious adverse effects being noticed.

We also recommend cycles be kept within this range, and to not exceed two cycles per year..

Best MK-677 Supplements | 2023 Edition

With the wide selection of MK-677 supplements on the market, it can be difficult to determine which vendor to trust when it comes to making a purchase. Hence, we set about researching the myriad of MK-677 supplements available online.

Ultimately, our team discovered a reputable source for buying MK-677 supplements from, according to certain parameters.

  • How’s their shipping?
  • What is their manufacturing process like?
  • Do their products have positive, verified reviews?

We’ve answered all these questions and more.

Coming in as our number one recommendation for a vetted and reputable source to buy MK-677 capsules from, would be Chemyo. Here’s why:

  • Reliable shipping. Their shipping is world class, as they can send your purchase to any country. In fact, they offer free shipping on international orders over $275.
  • Optimal dosing. Chemyo MK-677 is dosed at 25 milligrams per milliliter.
  • Pure ingredients. One advantage that Chemyo MK-677 has over competing products, is that it is third party tested for its identity, purity, and concentration. Their products are all produced in accordance with high standards of quality in an FDA-approved facility in the United States.
  • Positive customer reviews. Chemyo MK-677 stood at over 45 positive reviews from verified customers at the time this article was written in early 2023, which is a trustworthy sign that their product actually works as advertised.

We recommend grabbing at least two bottles so that you have enough to complete a proper 12-week cycle.

As you can see, there’s a number of reasons why Chemyo MK-677 is our #1 recommended MK-677 supplement.

Order MK-677 from our top-rated USA vendor...

What is MK-677? | Overall

In conclusion…

That wraps up our article answering the question ‘what is MK-677?’. We’ve covered why MK-677 was developed, how it can consumed optimally, and how it can help bodybuilders enhance their physique.

Generally, MK-677 is safe to use and produces virtually no adverse side effects.

While MK-677 isn’t technically illegal, it isn’t permitted for use in professional sports competitions like the Olympics, as per a ruling by WADA, the World Anti-Doping Agency. This could be due to the fact that more human trial data needs to be made available, in order to provide more evidence that it is safe for humans to consume.

Most of the confusion about whether MK-677 is a SARM or not originates from it being marketed alongside SARMs.

Again, it’s important to point out that MK-677 is not an anabolic steroid or a SARM. Some of the reasons for this, is because it doesn’t bind to androgen receptors in the body.

Ready to get started with MK-677?

If so, then Chemyo is our #1 recommendation for a reliable online MK-677 vendor.

We like Chemyo because they put all of their products through rigorous 3rd-party testing standards. This means you get the highest quality product available anywhere in the world.

So what are you waiting for?

Pick up a bottle of Chemyo MK-677 today and take your physique to the next level!


  1. M. G. Murphy, L. M. Plunkett, B. J. Gertz, W. He, J. Wittreich, W. M. Polvino, D. R. Clemmons, MK-677, an Orally Active Growth Hormone Secretagogue, Reverses Diet-Induced Catabolism, The Journal of Clinical Endocrinology & Metabolism, Volume 83, Issue 2, 1 February 1998, Pages 320–325, https://doi.org/10.1210/jcem.83.2.4551
  2. Ian M. Chapman, Ora H. Pescovitz, Gail Murphy, Theresa Treep, Kristine A. Cerchio, David Krupa, Barry Gertz, William J. Polvino, Emily H. Skiles, Suzan S. Pezzoli, Michael O. Thorner, Oral Administration of Growth Hormone (GH) Releasing Peptide-Mimetic MK-677 Stimulates the GH/Insulin-Like Growth Factor-I Axis in Selected GH-Deficient Adults, The Journal of Clinical Endocrinology & Metabolism, Volume 82, Issue 10, 1 October 1997, Pages 3455–3463, https://doi.org/10.1210/jcem.82.10.4297
  3. Nass R, Pezzoli SS, Oliveri MC, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med. 2008;149(9):601-611. doi:10.7326/0003-4819-149-9-200811040-00003
  4. Ishida, J., Saitoh, M., Ebner, N., Springer, J., Anker, S. D., and von Haehling, S. (2020) Growth hormone secretagogues: history, mechanism of action, and clinical development. JCSM Rapid Communications, 3: 25– 37. https://doi.org/10.1002/rco2.9.
  5. Lee, J., Kwon, A., Chae, H. W., Lee, W. J., Kim, T. H., & Kim, H.-S. (2018, November 15). Effect of the orally active growth hormone secretagogue MK-677 on somatic growth in rats. Yonsei Medical Journal. Retrieved May 3, 2022, from https://synapse.koreamed.org/articles/1107574
  6. Dr. Idiberto Jose Zotarelli Filho, M. S. (2020, May 23). Major approaches the use of GH secretagogue (MK-677) for muscle mass gain in elderly: A brief systematic review. Authorea. Retrieved May 3, 2022, from https://www.authorea.com/doi/full/10.22541/au.159050681.10910720
  7. Smith, R. G. (2005, May 1). Development of growth hormone secretagogues. OUP Academic. Retrieved May 3, 2022, from https://academic.oup.com/edrv/article/26/3/346/2355231?login=true
  8. Svensson, J., Lönn, L., Jansson, J.-O., Murphy, G., Wyss, D., Krupa, D., Cerchio, K., Polvino, W., Gertz, B., Boseaus, I., Sjöström, L., & Bengtsson, B.-A. (1998, February 1). Two-month treatment of obese subjects with the oral growth hormone (GH) secretagogue mk-677 increases GH secretion, fat-free mass, and Energy Expenditure1. OUP Academic. Retrieved May 3, 2022, from https://academic.oup.com/jcem/article/83/2/362/2865156?login=true
  9. Copinschi, G., Leproult, R., Onderbergen, A. V., Caufriez, A., Cole, K. Y., Schilling, L. M., Mendel, C. M., Lepeleire, I. D., Bolognese, J. A., & Cauter, E. V. (2008, April 9). Prolonged oral treatment with MK-677, a novel growth hormone secretagogue, improves sleep quality in man. Neuroendocrinology. Retrieved May 5, 2022, from https://www.karger.com/Article/Abstract/127249
  10. Anabolic steroids. (n.d.). Retrieved February 18, 2022, from https://www.deadiversion.usdoj.gov/pubs/brochures/steroids/public/
  11. Cronkleton, E. (2019, March 29). HGH: Side effects in men and women. Healthline. Retrieved May 5, 2022, from https://www.healthline.com/health/hgh-side-effects#side-effects
  12. The prohibited list. World Anti-Doping Agency. (2022, February 9). Retrieved May 5, 2022, from https://www.wada-ama.org/en/prohibited-list?q=growth+hormone+secretagogue
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