I have been researching into the Osta-Red supplements online. From the reviews I have been reading they seem to be great for lean muscle mass building without water retention or potential side effects that are normally associated with Steroids.

Is this an effective suppplement? And should I be taking any other supplements or be taking any pre-cautions simultaneously. Thanks.

2 Answers 2


First of all, you'd need to know what it is you're getting. Osta-Red contains ostarine, which is another name for a substance known as enobosarm. Its chemical formula is (or should be) (2S)-3-(4-cyanophenoxy)-N-[4-cyano-3-(trifluoromethyl)phenyl]-2-hydroxy-2-methylpropanamide. However, the name "ostarine" has also become associated with andarine, which has chemical formula (2S)-3-(4-acetamido-phenoxy)-2-hydroxy-2-methyl-N-(4-nitro-3-trifluoromethyl-phenyl)-propionamide, which is a similar but still different beast. From the Osta-Red site it seems that what you're getting is enobosarm, so let's focus on that.

Enobosarm was originally developed by pharma company Merck & Co. and is now developed by GTX, Inc. They're specialized in drugs influencing hormonal pathways. The formula given above was not publicly disclosed but it can be found through patents. It is an investigational substance, meaning its full range of effects and side-effects cannot be expected to be completely known. Anyone who'd try to sell this claiming it is safe or fully approved is lying through their teeth.

That's not to say there is no medical literature, but certainly not as much as is needed. On PubMed Central the most interesting thing I'm finding is this: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3177038/ (The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II trial; J Cachexia Sarcopenia Muscle. 2011 Sep; 2(3): 153–161). There are other studies regarding selective androgen receptor modulators (SARMs), of which enobosarm is one, which might be interesting.

One important thing of note is that this stuff is banned by the world anti-doping agency, meaning that if you want to compete in a sport there will be plenty of federations who could find it a reason for exclusion, and you could get into trouble for things outside of competition, such as drug tests in other contexts.

A second important thing is that this is a drug influencing your hormonal system. The idea behind SARMs is that they get some of the benefits you could get from hormones such as testosterone or anabolic steroids, while being selective enough in receptor activation to avoid side-effects that would occur from the effects on non-target tissues (for example, anything outside of skeletal muscle). Just because they aren't technically anabolic steroids or hormones doesn't mean it's safe to be messing with your hormonal regulation. With steroids and hormones, despite the potential for negative effects at least they've been extensively studied and you get some idea of what you're getting yourself into.

Now the Osta-Red site at least seems honest about a lot of these points. They note how the substance can make you fail doping tests, that this stuff is experimental and they don't seem to try to peddle it to folks who have no business hopping onto supplements. That's something that speaks in their favor. I'd still go looking for reports doing actual chemical analysis to make sure you're getting enobosarm, and only that.

Bottom line is, this thing is a wildcard and I don't think you should feel comfortable being the guinea pig for testing it. Could SARMs turn out to be amazing things that will benefit muscle growth and retention with nearly no side-effects? Certainly. But we just don't know enough yet and, at least to me, that makes the potential risks outweigh benefits.

  • +1 great answer. I really don't understand the need from so many people to use close-to-steroids.
    – John
    May 17, 2016 at 7:21
  • @JJosaur It's the alluring promise of an easy boost at no risk. Regular steroids carry risks and require plenty of study to figure out how to use them properly and get the best out of them (I know very little about them so I reserve my judgement). If something promises stimulated growth and strength without those risks and as simple as popping a pill, it's very easy to think "why not?". In the end it's a risk/reward call, but the problem is the risks and rewards might not be properly presented. I wouldn't even take creatine without first reading up on it.
    – G_H
    May 17, 2016 at 7:31

Osta-red is ostarine, or more commonly known as, Enobosarm. Answer below is adapted from the elite fitness forum

What is Ostarine?

Ostarine is the SARM (Selective androgen receptor modulator) that GTx is developing for the prevention and treatment of muscle wasting. It is currently undergoing clinical trials and may eventually be the medical prescription for prevention of cachexia, atrophy, and sarcopenia and for Hormone or Testoserone Replacement Therapy.

SARMs create selective anabolic activity at certain androgen receptors and not others, hence their name. Compared to testosterone and other anabolic steroids and pro hormones, the advantage of sarms such as (Ostarine) MK-2688 is that they do not have androgenic activity in non-skeletal-muscle tissues. Ostarine is effective in not only maintaining lean body mass (LBM) but actually increasing it.

SARMs were banned by the World Anti-Doping Agency in January 2008 despite no drugs from this class yet being in clinical use, and blood tests for all known SARMs have been developed.

Enobosarm (Ostarine, MK-2866, GTx-024) – affects both muscle and bone, intended mainly for osteoporosis but also general treatment for andropause and reversing muscle sarcopenia in the elderly and for cachexia in cancer patients

How does it work? (The science bit)

Selective androgen receptor modulators (SARMs) bind to the androgen receptor and demonstrate osteo (bone) and myo (muscular) anabolic activity. Androgen receptor activation

Binding and activation of the Androgen receptor alters the expression of genes and increases protein synthesis, hence builds muscle. So in essence, sarms such as Ostarine causes muscle growth in the same manner as steroids, however unlike testosterone and other anabolic steroids and prohormones, sarms (as nonsteroidal agents) don’t produce the growth effect on prostate and other secondary sexual organs.

Ostarine in particular exerts its anabolic effects on muscle tissue almost exclusively. So not only does it represent a new potential treatment option for a wide spectrum of conditions from muscle wasting diseases (from age-related to AIDS or cancer-related), but is also has immense potential for muscle building for Bodybuilders, fitness, athletes and an agent to minimize atrophy during recovery periods from serious surgery or similar situations.

Evidence of Ostarine’s Abilities?

To date, GTx has evaluated Ostarine in eight clinical trials involving approximately 600 subjects including three efficacy studies. A four month Phase IIb clinical trial enrolled 159 patients with the study meeting its primary objective of an absolute increase in total lean body mass (muscle) compared to placebo and the secondary objective of muscle function (increase in strength).

In particular application to bodybuilding, there have been many logs of users on various forums using Ostarine as an aid to increase lean body mass and strength levels.

Uses of Ostarine

Lean muscle gains (bulking)

As Ostarine is the most anabolic of the available sarms, its first and foremost use must be when trying to gain lean muscle. The gains in absolute weight won’t be comparable to steroids such as diannabol, however what will be gained will almost exclusively be lean mass. Due to the lack of shutdown in comparison to steroids/prohormones, a PCT - post cycle therapy - period is not needed and almost all the mass that is gained on Ostarine is kept once the cycle is finished.

Doses of 25mg for 4-6 weeks are the most common protocol for such goals. Over this 4-6 week period will typically produce 6lbs or 3kg of lean, keepable gains. However the abundant side effects of steroids/prohormones will not be present.

Users have as high as 36mg [only recommended for those who weigh in at 210lbs (95kg)+] for periods as long as 8 weeks. However the potential for suppression from such doses is higher and users would have to look into a PCT - post cycle therapy - protocol after undergoing such a cycle. As the majority of Ostarine supplies come in 30ml bottles at 25mg/ml, a dose of 17.5mg per day will give the user a 6 week cycle from one bottle, a very good compromise between an anabolic dose and cost.

Losing Bodyfat (cutting)

Ostarine would primarily fit into a cutting protocol for the maintenance of muscle mass whilst reducing calories.

The drop in metabolic rate and hormone levels (T3, IGF, Testosterone etc) with the lack of calories is a perfect catabolic environment for loss of muscle tissue. As Ostarine has anabolic effects, the dieter can cut calories without having to worry about muscle or strength loss. Ostarine has also shown noticeable nutrient partitioning effects among users, another reason why it can be of great help when cutting.

A 12.5-15mg dosing protocol for 4-6 weeks is good for cutting with Ostarine without undergoing any side effects or suppression. However it must be stated that due to the lack of androgenicity, muscle hardness and overall results are not as prominent as with the SARM S-4.

Recomping (gaining muscle and losing body fat at the same time)

Recomping is where Ostarine really shines. The recomping effect of losing fat and gaining muscle at the same time is what the majority of users are looking for. Trying to achieve this when you are not absolutely new to training is extremely difficult.

Where Ostarine shines for recomping is in its nutrient partitioning benefits. Calories are taken from fat stores and calorie intake is fed to the muscle tissue. In fact many users report that Ostarine consumed at maintenance calories produces weight loss, whilst still getting increases in strength and muscle mass!

One of the most important factors of recomping is TIME. As you are trying to achieve multiple objectives, it requires a longer time period to notice good recomp effects so even when running steroids, these would have to be longer run injectible compounds as oppose to the short used liver toxic oral steroids/prohormones.

Although Ostarine is taken orally, as it is not methylated it is not as liver toxic as other oral steroids/prohormones. Therefore it can be run for longer than the standard 4 week period with the aforementioned compounds.

The dosing protocol of 12.5-25mg for 4-8 weeks will give excellent recomp effects.

Diet must also be optimized to where calories are just above maintenance with at least 30% coming from lean sources of protein to get the best recomp effect.

Injury Prevention

The effects of MK-2688 translate to anabolism in bone as well as skeletal muscle tissue, which means it could be used in the future for a wide variety of uses such as osteoporosis and as a concurrent treatment with drugs that reduce bone density. Therefore, it has great application as a compound to use for rehabilitation of injuries, in particular bone and tendon related injuries.

Doses of 12.5mg per day is recommend for such purposes and improvement in joint movement that can be seen after just 6-8 days.

Timing of Doses

As Ostarine has a half life of around 24 hours, each of these doeses only has to be taken orally once a day, therefore its also offers an extremely convenient supplementation intake.

Advantages Of Ostarine when compared to Steroids/Prohormones

  • There is no need for pre cycle supports such as Hawthorn berry.
  • There is no need for on cycle supports such as milk thistle for the liver, policosanol or RYR for cholesterol etc.
  • Some suppression may be present at doses of 25mg+ run for longer than 4 weeks, however a stringent PCT - post cycle therapy - of prescription serms like nolva or Clomid is not necessary.
  • High oral biovailabilty without significant damage to your liver as with oral steroids/prohormones.
  • Great sense of well being while on, (without the aggression which can often detrimentally impact users daily lifes).
  • No need for a long time period off between cycles; the recommended time of period for normal cycles would be Time on +PCT - post cycle therapy - , so for a typical 6 week cycle and 4 week PCT - post cycle therapy - , a user would have to wait another 10 weeks after PCT - post cycle therapy - to start another cycle.

Advantages Of Ostarine when compared to other SARMS

  • The metabolite M1 wich seems to cause toxicity in S4 (temporary occular disturbances) is not present in Ostarine.
  • Unlike S4, Ostarine does not have androgenic properties in non muscle tissue.

Ostarine Summary

  • Anabolic even at doses as low as 3mg
  • Great for strength
  • Great for lean mass gains
  • Great for body recomposition
  • Great for endurance (aerobic or anaerobic)
  • Joint healing abilities
  • Half life of circa 24 hours – only once a day dosing required

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