S4 vs Ostarine: what to choose and for whom

Andarine (S4) and Ostarine are often marketed as “mild” options for a first acquaintance with sports pharmacology. The editorial team considers this logic mistaken and explains why, for most people, the question “what to choose” has the answer “neither”, as well as what those who still weigh the risks should know.

Where the myth of an “easy start” comes from

In SARM marketing, the image of a “safe step before steroids” has taken hold. Ostarine is called the mildest, andarine the “cutting” one. Both descriptions have little to do with science: they come from forums and sellers’ sites, not from clinical studies.

In reality both substances are androgen receptor agonists and, as studies of enobosarm have shown, they suppress one’s own testosterone production and lower the level of “good” cholesterol. So “mildness” is a relative concept and depends on the dose, duration and individual characteristics.

Another component of the myth is the oral form. Psychologically it is easier for people to swallow a capsule than to give an injection, and this creates the illusion of lower risk. But the route of administration does not determine safety: oral drugs pass through the liver, and it is precisely SARMs that are linked to cases of drug-induced liver injury.

Finally, an “easy start” often becomes not the last step but the first in a chain. That is why the editorial team suggests treating the choice between S4 and Ostarine as a decision about whether to enter the sphere of unregistered hormonal substances at all.

Comparison by risk criteria

If one is nonetheless going to compare the two substances, it is worth doing so not by the “effect on definition” but by how well their risks are known. In this sense Ostarine has the advantage only in that more data have been published on it — including on side effects.

For andarine, mostly studies in rats are available, and in humans there are user reports of vision disturbances (a yellowish tinge, impaired night vision). There are no controlled studies that would confirm or refute this effect and determine whether it is reversible.

As the table shows, no criterion makes either substance “safe”. The difference lies only in the degree of uncertainty.

It should also be taken into account that any effect on muscle obtained while using a SARM is partly lost after stopping, whereas recovery of the hormonal system can take weeks or months.

Who definitely should not

There are categories of people for whom the risks of both substances clearly outweigh any imagined benefit. The editorial team singles them out separately, because it is precisely these groups that most often become the target of “mild SARM” advertising.

• Athletes subject to doping control,— both substances are banned at all times.
• Women— the risk of virilization (a deepening voice, facial hair growth), some changes are irreversible.
• People under 25— the hormonal system and bone tissue are still maturing.
• People with vision disturbances, liver diseases or dyslipidemia.
• Men planning fatherhood— suppression of spermatogenesis.

Separately, a word should be said about people with anxiety about their appearance or signs of muscle dysmorphia. For them the problem often does not lie in the muscles, and no substance solves it; here a specialist consultation is more appropriate.

For the remaining adult readers the editorial team formulates a simple rule: if you are not ready to have lab tests regularly and discuss the results with a doctor, you cannot even assess whether the substance is causing harm.

And if you are ready, it is worth first discussing with a doctor whether you have a medical problem that can be solved with registered treatments.

Which lab tests show the real price

Even without taking any substances, a basic medical checkup is useful for anyone who trains seriously. It provides a baseline against which changes can be compared. For people who have already used SARMs, these same tests help assess the consequences.

The main panel usually includes a lipid profile (total cholesterol, HDL, LDL, triglycerides), liver tests (ALT, AST, bilirubin), total testosterone, LH and FSH, and a complete blood count. They should be interpreted by a doctor taking training into account: intense loads by themselves can temporarily raise some values, for example AST.

A decrease in LH and FSH against a background of low testosterone is a typical picture of suppression of the hormonal axis by exogenous androgens. Recovery after discontinuation occurs in many people, but its timing is individual.

For any changes in vision, jaundice, darkening of the urine or pronounced weakness, one should immediately see a doctor and report all substances taken — this will help establish the cause faster.

A legal alternative and editorial conclusions

For building muscle and improving body composition, progressive strength training, sufficient protein (1.4–2.0 g/kg per day per the ISSN position) and creatine monohydrate (3–5 g per day) work in an evidence-based way. For “cutting” — a moderate calorie deficit with maintenance of high protein and strength loads. These tools do not deliver instant results, but they do not take away your health.

Comparing S4 and Ostarine, the editorial team concludes: Ostarine is better studied but has confirmed side effects; andarine is studied worse and is known for reports of vision disturbances. For a healthy person without medical indications, neither substance is a rational choice.

If, however, the reason for the interest in SARMs is a real problem — loss of muscle after an injury, an age-related decline in testosterone — it is worth solving it with a doctor who has registered treatments with a known safety profile at their disposal.

We also recommend reading our materials “S4 or Ostarine: what is the difference”, on creatine monohydrate and on the lipid profile for people who train.

References

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