Dear Guru Maharaja, please accept my humble obeisances.

All glories to Srila Prabhupada!

Modern science confirms* that every seven years all the cells in the body are changed. That in the range of seven years all the cells in the body are changed.

We use this fact as a example of reincarnation, even in this body.

Srila Prabhupada agreed with this statement.

ASA - Even the nerve cells?  We Googled the fact and got some references that say it is not precise, but yes the cells replace, and still says that the brain neurons are not replaced, but I hear that there is new research about this now.

How it is that those new cells take a form (or qualities) of aged body? For example, the aged body forms wrinkles around the eyes and the new cells maintain those wrinkles (or even makes more of it) instead to being new as in a young body. Or if a person has a tattoo, after seven years that tattoo is still there, it does not vanish. We would understand that a new cell will have a new untouched quality but it is not so.

Your servant Namacarya das

* of course, as in every statement, this one also has  opposed ones

~~~

Dr. Singh. Medical science says that all the bodily cells are replaced every seven years.

Srila Prabhupada. No, not every seven years -- every second. Every second, the blood corpuscles are changing. Is it not so?

Dr. Singh. Yes.

>>> Ref. VedaBase => Changing Bodies

HpS - ASA -- We don't have any specialist knowledge in this. Maybe Dr. Nikunja bihari Das has some information. You questions about skin condition is certainly interesting.