Which Steroids Don’t Aromatize and Cause Gyno

  • By: Dave Moffat
  • Date: December 8, 2023
Which Steroids Don't Aromatize

Steroids are a hot topic with lots of interest and debate in the world of fitness and bodybuilding. They can really help improve how you perform and how your body looks, but they can also cause side effects.

One side effect of steroids is aromatization. Aromatization occurs when steroids convert to estrogen due to the enzyme aromatase.

This can lead to effects that people might not want, like holding onto too much water and gynecomastia (when a man’s breasts get bigger).

But not all steroids go through this process. Non-aromatizing steroids, like their name suggests, don’t turn into estrogen, so they avoid these side effects.

This article explores non-aromatizing steroids. It examines their definition, popular examples, side effects, and associated risks.

Our goal is to give you all the information you need to make smart choices about using steroids.

Whether you’re a bodybuilder with experience or just starting out, keep reading to learn more about non-aromatizing steroids.

Aromatization: A Brief Overview

Aromatization is a natural process that happens in our bodies. An enzyme called aromatase changes androgens into estrogens. Androgens are boy hormones while estrogens are girl hormones. This process is really important for keeping a balance of these hormones in both boys and girls.

Androgens like testosterone and androstenedione can be changed by the aromatase enzyme. Androgens enter cells. Aromatase enzyme in endoplasmic reticulum converts them to estradiol and estrone.

Boys need estrogen for healthy bones and brain function. However, excessive estrogen can lead to problems. When discussing anabolic steroids, which are types of testosterone, this becomes crucial. Some anabolic steroids can be changed into estrogen through aromatization.

That’s where the aromatase enzyme comes in. It’s what changes these steroids. For example, if someone takes a steroid like testosterone enanthate, the aromatase enzyme can change it into estradiol.

The more active the aromatase enzyme is or the more androgens there are that can be changed, the more they’ll turn into estrogen. This can cause a hormone imbalance and lead to problems like holding onto too much water, gaining fat, and gynecomastia.

But it’s important to remember that not all steroids can be changed like this. Non-aromatizing steroids, discussed later, are unaffected by the aromatase enzyme. Therefore, they are a suitable option for individuals who wish to avoid aromatization-related issues.

Non-Aromatizing Steroids: What Are They?

Non-aromatizing steroids are a kind of anabolic steroids. They do not convert into estrogen in the body. That is why they are called ‘non-aromatizing’. This means that when they break down in the body, they don’t make the girl hormone estrogen because the aromatase enzyme isn’t involved.

Anavar, Winstrol, Masteron, and Trenbolone are non-aromatizing steroids. Steroids are frequently used to build muscle without estrogen’s side effects.

Some athletes and bodybuilders prefer non-aromatizing steroids because they want to avoid these side effects related to estrogen.

Anabolic steroids can cause problems when they convert to estrogen. These problems include water retention, fat gain, and gynecomastia. These side effects can be a big problem for bodybuilders who want a lean, muscular body.

High levels of estrogen can also lead to other health problems, like high blood pressure and imbalances in cholesterol. People can improve performance by using non-aromatizing steroids. These steroids provide the benefits of steroids without the side effects.

Non-aromatizing steroids lower the chance of estrogen-related side effects. However, they can still have other side effects and risks. We will discuss these later in the article.

Popular Non-Aromatizing Steroids

Non-aromatizing steroids are favored by athletes and bodybuilders. They help build muscle mass and enhance performance without converting to estrogen.

Typically, these don’t cause estrogen-related side effects such as water retention. They also don’t cause gynecomastia, which is male breast enlargement.

Here’s information about four popular non-aromatizing steroids:

  • Anavar (Oxandrolone): Anavar is a mild anabolic steroid known for its low androgenic activity. It’s often used during cutting cycles to maintain lean muscle mass while losing body fat. Anavar promotes increased strength, improved muscle density, and enhanced recovery. However, it can cause side effects like hair loss and acne in predisposed individuals.
Legal Anavar Alternative
  • Winstrol (Stanozolol): Winstrol is another popular non-aromatizing steroid, often used during cutting cycles to preserve lean muscle mass and enhance muscular definition. It’s also known for promoting strength and endurance without unwanted water retention. Despite its benefits, Winstrol can have negative effects on cholesterol levels and liver health.
Legal Winstrol Alternative
Winsol by Crazy Bulk

Benefits of Winsol

  • Winsol preserves lean muscle mass whilst stripping fat
  • Gives you a ripped competition & beach physique
  • Rock-hard defined muscles
  • Enhanced vascularity
  • Super strength & endurance
  • Maximum power, speed & agility for running



  • Masteron (Drostanolone): Masteron is known for its strong anti-estrogenic properties, making it a popular choice among bodybuilders looking to avoid water retention and achieve a hardened and defined look. It’s typically used during the final weeks leading up to a competition. Side effects can include hair loss, acne, and aggression.
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  • Boosts testosterone production
  • Increases free testosterone levels
  • Slows conversion of testosterone to estrogen
  • 100% Safe & Natural
  • Fast, Noticeable Results


  • Trenbolone: Trenbolone is one of the most potent anabolic steroids available. It’s known for its ability to promote significant muscle growth, enhance fat loss, and increase strength. Despite not aromatizing, Trenbolone can cause estrogen-like side effects. These side effects are caused by its progestational activity. It can also have significant impacts on mood and cardiovascular health.
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Trenorol by CrazyBulk

Benefits of Trenorol

  • Shred fat without losing mass
  • Super strength & stamina
  • Amazing physical conditioning
  • Enhanced vascularity
  • Helps reduce recovery time between workouts without sacrificing muscle mass


Weighing the Pros and Cons: Side Effects and Risks

When it comes to using non-aromatizing steroids, it’s important to consider both the potential benefits and risks. These substances can increase muscle growth and enhance performance. However, they also have common side effects and potential risks.

Common Side Effects

Non-aromatizing steroids are usually well-tolerated. However, they can still cause side effects. These include:

  • Androgenic Effects: Despite their low estrogenic activity, non-aromatizing steroids can still cause androgenic side effects such as acne, hair loss, and increased body hair growth, particularly in individuals who are genetically predisposed to these conditions.
  • Cardiovascular Issues: Steroids like Winstrol and Trenbolone can have negative effects on cholesterol levels, potentially increasing the risk of heart disease over time. They can also lead to increased blood pressure.
  • Mood Changes: Some users report mood changes, including increased aggression and irritability, particularly with potent steroids like Trenbolone.
  • Liver Damage: Oral steroids like Anavar and Winstrol can be hard on the liver, particularly when used in high doses or for extended periods.

Potential Risks

In addition to these common side effects, there are also several potential risks associated with non-aromatizing steroid use:

  • Dependency and Addiction: While less common than with other substances, it is possible to become psychologically dependent on steroids, leading to withdrawal symptoms when usage is stopped.
  • Long-Term Health Consequences: Prolonged use of anabolic steroids can lead to long-term health issues such as heart disease, liver damage, and fertility issues.
  • Legal and Ethical Considerations: In many jurisdictions, it’s illegal to use anabolic steroids without a prescription. There are also ethical considerations around their use in competitive sports.

Steroids Notorious for Causing Gynecomastia

Gynecomastia, also known as gyno, is a common side effect of steroid use. An overabundance of estrogen can disrupt hormone balance in the body. This disruption can lead to breast tissue enlargement in males.

Here are a few steroids notorious for causing gyno:

  • Dianabol (Methandrostenolone): Dianabol is one of the most well-known oral anabolic steroids and is notorious for its propensity to cause gynecomastia because it aromatizes easily into estrogen.
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D-Bal by Crazy Bulk

Benefits of D-Bal

  • Increases muscle mass while reducing recovery time
  • Helps increase the amount of oxygen your body can utilize during workouts
  • A safe and legal alternative to Dianabol
  • Contains Ashwagandha which has been proven to improve overall performance
  • Fast muscle gains
  • Super strength and stamina


  • Anadrol (Oxymetholone): Anadrol is another powerful steroid that can cause gyno. It’s not known to directly convert to estrogen. However, it’s believed to have progestogenic activity. This activity can stimulate the estrogenic pathway.
  • Deca-Durabolin (Nandrolone Decanoate): While Deca-Durabolin has a low rate of aromatization, it has strong progestogenic activity which can increase the risk of developing gyno.
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DecaDuro by CrazyBulk

Benefits of DecaDuro

  • Explosive power and strength for runners during competitions
  • Preserve lean muscle whilst reducing body fat
  • Relieve joint & tendon pain
  • Fast muscle recovery after grueling workouts
  • Testosterone: All forms of exogenous testosterone can convert to estrogen in the body through the process of aromatization, thus increasing the risk of gynecomastia.
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Testo-Max by Crazy Bulk
  • EXTREME Strength
  • Enhances Performance
  • Reduces Recovery Time
  • Pre-Breakfast


It’s important to note that not everyone who uses these steroids will develop gynecomastia. Several factors can influence the likelihood of this side effect. These factors include genetics, dosage, duration of use, and overall health. Always consult with a healthcare provider before starting any steroid regimen.


Non-aromatizing steroids such as Anavar, Winstrol, Masteron, and Trenbolone are popular. Steroids build muscle and enhance performance. They don’t cause estrogen-related side effects like other steroids.

But it’s really important to remember that these substances can still have risks and side effects.

Common side effects can include acne, hair loss, cholesterol problems, mood changes, and liver damage. There are more serious risks when using them. These risks include the chance of becoming dependent on them, long-term health problems, and legal and ethical issues.

In the end, the decision to use non-aromatizing steroids should be made with a good understanding of both the good and bad sides.


How do non-aromatizing steroids differ from other steroids?

Non-aromatizing steroids differ from other steroids in that they do not convert into estrogen in the body. Typically, they don’t cause estrogen-related side effects like water retention. They also don’t cause gynecomastia. Some steroids, called aromatizing steroids, can change into estrogen. This can cause potential side effects.

Why might someone choose to use non-aromatizing steroids?

Someone may opt for non-aromatizing steroids. These steroids help gain muscle and strength without estrogen-related side effects. These side effects include water retention and male breast enlargement. Other types of steroids often cause these side effects.

What precautions should be taken when using non-aromatizing steroids?

Precautions when using non-aromatizing steroids include:

  • Medical Supervision: Always use these substances under the guidance of a healthcare provider to monitor for potential side effects and adjust dosages as needed.
  • Regular Health Check-ups: Regular blood tests and health check-ups are critical to monitor liver function and cardiovascular health.
  • Dosage: Never exceed the recommended dosage. Higher doses can increase the risk of side effects.
  • Healthy Lifestyle: Maintain a balanced diet, adequate hydration, and regular exercise to support overall health while using these substances.
  • Avoiding Prolonged Use: Long-term use can lead to potential health risks, so cycles should be limited in duration with adequate off periods.
  • Understand the Risks: Be aware of the potential side effects, including androgenic effects such as acne and hair loss, and more serious risks like liver damage and cardiovascular issues.

How does the aromatase enzyme contribute to steroid aromatization?

The aromatase enzyme converts androgens, such as testosterone, into estrogen. This process is known as steroid aromatization.

Steroids can convert and increase estrogen, causing water retention and gynecomastia. Non-aromatizing steroids do not interact with this enzyme and thus do not convert into estrogen.

Dave Moffat

Hi, I'm Dave Moffat the founder and Chief Editor of steroidsourcetalk.com and certified International Personal Trainer and Certified Nutritionist. My passion has always been bodybuilding but with 15 years' experience in weight loss programs too, it's hard not to mention all that when you're working at your fitness level fullest (I hope). When Im not in the gym or spending time away from my family i often think about what advice would help others achieve theirs goals just like these inspired mine.