YK11 Side Effects: 3 Things to Watch Out For

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Three side effects of the SARM known as YK11

The jury is still out on whether YK11 is a selective androgen receptor modulator (SARM) or a steroid. SARMs are a class of androgen receptor ligands that are considered to be a safer alternative to steroids.

This is because SARMs are selective in which part of the body they target whereas steroids are not. SARMs limit their impact to bones and muscles while steroids tinker with your reproductive organs too. But SARMs are banned for human consumption.

Initially, they were tested on mice and rats. The results showed that SARMs can cause a range of cancers in the test subjects. So, they never made it to the stage of human trials.

But they are available as research chemicals in the market because scientists are still exploring their use as therapeutic drugs. SARMs have proven to be useful in avoiding muscle wasting in individuals suffering from advanced cancer and end-stage renal diseases.

In fact, the underground fitness community says the cancers are a likelihood only when SARMs are used for a really long time in high dosage. That is why they recommend using SARMs in short cycles and in very small quantities to build lean muscle mass aka bodybuilding. Sportspersons also use SARMs because they are performance enhancers. This despite a ban by the World Anti-Doping Agency (WADA) on all SARMs.

Why YK11 Is Not Any Other SARM

Now, YK11 is a special case. Some call it a synthetic steroid based on dihydrotestosterone or DHT which is a hormone found naturally in the human body. DHT is a bit stronger than testosterone and targets the androgen receptors in the prostate, hair and liver.

YK11 is popular among bodybuilders because it helps build muscle really quickly. In the underground fitness community, many of them say it has minimal side effects. Now, it is important to note that a lot of information on SARMs is not backed by science because many of these compounds were not tested on humans. So, what you read on the internet is based on anecdotal evidence from individuals who have tried these products.

What we know about YK11 in terms of science is that the YK molecule has a lot in common with steroids than SARMs but it is often labelled as a non-steroidal SARM. However, like every other SARM, it is also consumed in two cycles: bulking and cutting. Bodybuilders have reported muscle gain and fat loss after using YK11 for a certain amount of time.

💡 Always buy SARMs from a reputable source like the ones found on the Source List >>

YK11 Side Effects

Nevertheless, it is important to educate yourself about the possible side effects of using YK11. Since there are no studies on this compound, the evidence of side effects comes from bodybuilding logs. While many users report no side effects whatsoever in the short term, some others had difficulties. So, here’s what we know.

Using YK11 might lead to:

  • testosterone suppression
  • increased follistatin levels
  • joint and tendon pain

Testosterone Suppression

Testosterone suppression is one of the biggest side effects. However, it is common for all SARMs from cardarine to Ligandrol. In most cases, users have reported mild suppression but this is expected even at a very low dosage of 5 mg.

You know it is testosterone suppression when your energy levels are low, you feel lethargic and/or depressed. So, when on YK11, it is best to prepare for upcoming suppression. This can be done with post-cycle therapy or PCT. Nolvadex and Clomid are used during PCT, which typically lasts for four weeks.

Increase Follistatin Levels

YK11 is also known to increase follistatin levels. This can lead to different types of cancers affecting the esophagus, skin, stomach and the prostate. But there is scientific evidence that states the benefits of increased follistatin levels when it comes to breast cancer. 

Researchers also say that using YK11 can damage your liver. This is because its chemical structure is close to steroids that are toxic for the liver.

Joint Pain

This has also been reported by some users who consumed YK11. It is probably because YK11 is a derivative of DHT and some of those derivatives are infamous for messing with proteins that in turn inhibit cortisol regulation in the body. It is possible that YK11 is interfering with pathways that facilitate cortisol secretion. This causes severe joint pain.

YK11 is also a myostatin inhibitor. Myostatin plays an important role in maintaining the tendons in our body. So, it has a negative impact on tendon strength too.

However, these side effects can be mitigated by taking supplements or doing post-cycle therapy. But the first thing to remember is to maintain a strict YK11 cycle and dosage. Here are a few guidelines.

YK11 Cycle and Dosage 

The general consensus is that YK11 is good for growing muscles and enhancing physical performance. If you are to take it, here’s how you do it.

Newbies must absolutely keep it limited to 10 mg per day. Intermediate users can go up to 15 mg per day and experienced users can take 20 mg per day but at their own risk. Taking 10 to 15 mg per day is considered optimal.

YK11 Bulking and Cutting Stacks

In the bulking stack, consider taking YK11 with Ligandrol and RAD 140. Here is a sample.

  • YK11 – 10 mg per day
  • Ligandrol – 10 mg per day
  • RAD 140 – 15 mg per day

During a cutting stack, you can pair it with cardarine and ostarine. Here’s a sample.

  • YK11 – 5 mg per day
  • Ostarine – 25 mg per day
  • Cardarine – 10 mg per day

Since it is more effective during a bulking cycle, it goes well with RAD 140 and Ligandrol.

💊 Which SARM Is Best For Your Goals? Take the quiz:


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SARM Picker Quiz
Your Result: Ostarine
Ostarine is an easy, consistent way to improve your physique. It's mild and can be used for both bulking and cutting. Women can safely use this SARM. New users of SARMs should start here. TEST >>
Your Result: LGD 4033
LGD 4033 is a reliable bulking agent that can help you pack on dry mass. It has very little side effects and can be ran for 8 weeks at a time. It stacks well with other SARMs and can be used to preserve mass while on a cut. Stack with RAD 140 for huge gains or with Cardarine to help melt off some extra fat while you bulk.
Your Result: RAD 140
RAD 140 is arguably the most powerful bulking SARM that currently exists. It does have a higher side effect profile than Ostarine or LGD 4033, but many feel that it is worth it. It is a staple in the advanced bulking stack. You can take it alongside LGD 4033, MK 677, and YK 11 to gain serious amounts of lean body mass in minimal time.
Your Result: Cardarine
Cardarine is not actually a SARM, but it is often referred to as one. It's main ability is to encourage rapid loss of bodyfat and increased endurance. It is a staple for many bodybuilders who are prepping for a show and need to lose excess body fat. Cardarine is best for those who are already doing cardio and want the ability to feel like they can go forever. Since it doesn't have any androgenic effects, females can safely use it.
Your Result: MK 677
This growth hormone secretagogue is a must add to any bulking or cutting stack. MK 677 increases the amount of HGH and IGF-1 that your body produces. Since it works by helping your body increase it's natural levels, you do not need to cycle off MK 677. It has zero notable side effects other than water retention. MK 677 works best when stacked with SARMs such as RAD 140 and LGD 4033 for a bulk, and Ostarine / Cardarine for a cutting cycle. MK 677 really shines in older users who have started to experience lower HGH levels. It can also be used by women safely.
Your Result: SR 9009
SR 9009 is a powerful SARM that has the ability to rapidly melt away excess bodyfat. It works by simulating your body's response to exercise. Users typically result large amounts of weight loss with an increase of body fat. Stack it with Cardarine for the ultimate cutting stack or use with Ostarine to lean bulk.

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Bottom Line

The thing to remember about YK11 usage is that it is a very strong compound with side effects that could be quite dangerous if you don’t stick to the cycle and dosage.

It is dangerous to use these chemicals without proper research because a lot of them are available in the black market and companies have a tendency to sell products that are watered down and have a lot of unwanted side effects. 

The way to avoid it is to buy high-quality SARMs from reputed dealers. Check out some of them here.

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