Best Prohormones on the Market

Best Legal Prohormone on the Market in 2020 for Cutting and Bulking

Before reviewing some of the best legal prohormone stacks on the market in 2020, we will briefly explain what are prohormones, are prohormones illegal, and why they are used by bodybuilders and athletes.

What are Prohormones – Are Prohormones Steroids?

Prohormones are constituents that are precursors of hormones, while in themselves they do not possess biological activity. The term prohormones were originally used in medicine in the mid-20th century.

A large number of natural prohormones are found in humans: proinsulin, the precursor of insulin, thyroxin, the precursor of triiodothyronine, etc.

As you may know, testosterone and growth hormone are the main hormones for muscle growth (anabolism processes), increasing muscle strength, slowing down catabolism reactions and reducing body fats.

In bodybuilding, prohormones are understood to be prosteroids, when ingested, are converted, usually by enzymatic cleavage of part of the molecule, into active anabolic steroids, such as testosterone, etc. Although the meanings of prohormones and steroids are not synonymous, as many believe. Prosteroids are only one type of prohormone.

Prohormones vs Steroids in Bodybuilding

In the past 20 years, prohormones have been actively used by sportspersons in bodybuilding, powerlifting, and other strength sports to grow muscles and increase strength. Initially, the key advantage of prohormones was their legal status, since formally they do not belong to anabolic steroids. Nevertheless, in recent years, many prohormones are registered along with steroids and their turnover is limited.

Today, manufacturers are constantly working to create new prohormones that are not yet recorded as banned, but it takes 1-2 years and after that, the product is withdrawn from circulation.  Usually, manufacturers claim that their prohormones are much safer than steroids, but in reality, this is not always the case.

  • Firstly, the main goal of the manufacturer is not to create a safer product, but to build a new formula that would have an anabolic effect and was not yet included in the banned list, while the safety issue goes to the background.
  • Secondly, the utmost prohormones are much weaker than anabolic steroids, and this explains the lower occurrence of negative effects. From which we can conclude that prohormones are safe no more than steroids if taken in moderate doses.

This constant race leads to the fact that prohormones that do not undergo any clinical trials appear on the market, and it often turns out that these products have quite serious health problems and side effects that even are more severe than classic steroids. It should be noted that prohormones are dietary supplements, which means that the quality regulation of these products is much lower than that of pharmaceuticals.

Keep in mind: Prohormones do not have pharmacological advantages compared to anabolic steroids and are usually much weaker than the latter, while side effects occur quite often due to poor quality control and the almost complete lack of research. There is also a possibility of delayed side effects, possible carcinogenic activity, and so on.

Best Legal Prohormones for Mass in 2020:

best prohormone for mass and bulking4-androstenedione

• Converted to testosterone
• Studies show that the conversion rate does not exceed 6%, which means that only the twentieth part of the supplement turns into testosterone.
• A high level of aromatization, that is, the likelihood of the progress of gynecomastia, edema and other side effects.
• High androgenic activity.

4-androstenediol (4-AD)

• Converted to testosterone
• Conversion Rate 15.76%
• Not convertible to estrogen
• It has less androgenic activity compared to 4-androstenedione because it does not turn into dihydrotestosterone.


• Converted to nandrolone (retabolil)
• Anabolic activity almost like testosterone
• Does not turn into estrogen
• Low androgenic activity


• Converts also to nandrolone
• The conversion level is slightly higher than the previous prohormone.

1-androstenediol (1-AD)

• Converted to 1-testosterone (dihydroboldenone)
• It has 7 times more anabolic activity and 2 times more androgenic activity compared to testosterone.
• Almost completely converted to active form when passing through the liver
• Does not aromatize (does not turn into estrogen)

1,4-androstadienedione (1,4 AD)

• Converted to boldenone
• High oral bioavailability
• Low degree of aromatization to estrogen (50% less compared to testosterone)
• Low androgenic activity

1-testosterone (1-T)

• Similar to testosterone
• Has 4 times greater bioavailability when taken orally compared to testosterone
• Does not turn into estrogen
• Not a prohormone

Side Effects and Clinical Studies

Prohormones have similar to anabolic steroids’ harmful effects. The expressiveness and frequency depend on the specific formula of each supplement.

prohormones side effects

It is widely known that athletes often take large doses of anabolic steroids to improve adaptation to training, increase muscle mass and/or speed up recovery during intensive training.

Prohormones (androstenedione, 4-androstenediol, 19-nor-4-androstenedione, 19-nor-4-androstenediol, 7-keto-dehydroepiandrosterone (DHEA), dehydroepiandrosterone (DHEA), etc.) are essential precursors of testosterone and others anabolic steroids while having a natural origin. Due to their natural origin, they became widespread among athletes.

Some data are confirming the ability of prohormones to increase the level of testosterone in the blood. Although, practically no evidence that the addition of prohormones can improve adaptation to working out in men around 30 years old with normal hormone levels.

Most studies show that prohormones have no outcome on testosterone levels, and some of them can increase estrogen levels and lower high-density lipoprotein (HDL) levels.

Thus, although prohormones can be used to maintain the level of male hormones in older age groups, they appear to be ineffective in terms of use in athletes. Besides, most sports organizations have banned the use of prohormones as “steroid-like substances.”

It should be remembered that taking prohormones will lead to a positive test for anabolic steroids. It is the intentional and unintentional use of prohormones (as part of various supplements) has recently turn out to be the reason for many positive tests in athletes.

Thus, you should carefully study the supplement’s components for the presence of prohormones. This is especially true of athletes whose sport prohibits taking these constituents. For instance, some prohormones are prohibited for sale in the US, since there was passed a special law concerning the use of anabolic steroids (Anabolic Steroid Control Act) in 2004. The only exception is dehydroepiandrosterone (DHEA), it has passed many clinical trials in older age groups.

Here is the list of banned by DASCA in 2014 and illegal prohormones in USA:

5α-Androstan-3,6,17-trione (A form of 6-oxo)

6-bromo-androstan-3,17-dione (A form of 6-bromoandrostenedione, an aromatase inhibitor)


4-chloro-17α-methyl-androsta-1,4-diene-3,17β-diol (“Halodrol”)

4-chloro-17α-methyl-androst-4-ene-3β,17β-diol (“P-Mag” or “Promagnon 25”)

4-chloro-17α-methyl-17β-hydroxy-androst-4-en-3-one (17a-methyl clostebol)

4-chloro-17α-methyl-17β-hydroxy-androst-4-ene-3,11-dione (“Oxyguno”)

4-chloro-17α-methyl-androsta-1,4-diene-3,17β-diol (“Halodrol” is listed twice)

2α,17α-dimethyl-17β-hydroxy-5α-androstan-3-one (“Methasterone” or “Superdrol)


2α,3α-epithio-17α-methyl-5α-androstan-17β-ol (“Epistane” or “Havoc”)

[3,2-c]-furazan-5α-androstan-17β-ol (“Furuza”)



17α-methyl-androsta-1,4-diene-3,17β-diol (“M1,4ADD”)

Estra-4,9,11-triene-3,17-dione (“Trendione”)


6α-Methyl-androst-4-ene-3,17-dione (Found in “Methyl-1 Pro”)

17α-Methyl-androstan-3-hydroxyimine-17β-ol (“The One” or “D-Plex”)

17α-Methyl-5α-androstan-17β-ol (“Methylandrostanol” / “Protobol”)

17β-Hydroxy-androstano[2,3-d]isoxazole (“Androisoxazole”)


4-Hydroxy-androst-4-ene-3,17-dione (“Formestane”)

[3,2-c]pyrazole-5α-androstan-17β-ol (“Prostanozol”)


[3,2-c]pyrazole-5α-androstan-17β-o (“Prostanozol”)

Recently, a new way to boost the level of endogenous testosterone was found – blocking the activity of aromatase. In 2 studies, the functions of aromatase inhibitors (androst-4-ene-3,6,17-trione) and (hydroxyandrost-4-ene-6,17-dioxo-3-THP ether and 3,17-diketo-androst- 1,4,6-triene) were researched. As a result, a significant increase in dihydrotestosterone levels was observed. The effect of supplements on the growth of lean muscles tissue was not done in one of the experiments, and no improvements in the other.

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