It's been measured but the exact number doesn't matter.
The issue with nandrolone
and DHN is not that DHN itself is in any way a problem. Having DHN is having more anabolic steroid. This is never a problem
Some anabolic steroids, such as say methyltrienolone, are relatively speaking extremely likely to bind an androgen receptor at a given time. So only a low level of such a steroid is needed to bind most of the receptors. Others are less likely to do so and so a higher level in the blood is needed to bind the same percentage of receptors. This is not a problem: one just takes more of one of those steroids that is less likely to bind (has lower "affinity.") Having more of this steroid is still a plus. It is not that it makes things worse to have it.
Instead, the issues with nandrolone and DHN is that nandrolone occupies the 5AR enzyme and thereby is at least somewhat (how much, I don't know) of a competitive inhibitor and will decrease the amount of conversion of testosterone
; and moreso, on a nandrolone-only cycle the total amount of steroid is usually not that great and in tissues high in 5-AR, these tissues receive less androgenic effect than most of the body does because they are in effect seeing a lower level of steroid. (The actual total amount is the same, but DHN is less likely to bind, so it is as if level is lower.)
In contrast, most other synthetics are unchanged by 5-AR so these tissues "see" the same effective level as the rest of the body, or testosterone is actually potentiated.
dick" is meant, by the person, to refer to function of the penis itself and the cycle is Deca-only or doesn't have much of other anabolic steroids, lack of DHT
and lack of much else in terms of androgenic steroids may indeed be the problem.
However, the problem also includes low libido
, and can occur -- as with the penis problem -- despite having what should be sufficient androgenic effect from other androgenic steroids being used. So here, conversion of nandrolone to DHN cannot be the problem.
I would say the problem is at both the penis and in the brain, but in some instances an individual's difficulty could be more from one effect than the other.
The erectile-function effect can be fixed with testosterone, trenbolone
, and probably others. The effect at the brain unfortunately in many cases is not fixed by any of these.