Analysis Watch — Yuji Itadori

I didn't Find a Good Explanation for this, So here it Goes —

Stem Cells

Stem Cells are primarily responsible for Regenerating

1. Fat Cells

2. Skin Cells

3. Red Blood Cells

As well as Healing Injuries.

Since the Death Painting Wombs use Cursed Energy to create Red Blood Cells, it's natural to determine the process is different, but the result is identical.

Yuji's Stem Cells never NEED to produce Red Blood Cells and thus Yuji ages Slower.

It's literally the limited divisions of his stem cells being used exclusively for other purposes since the death painting wombs generate plenty of blood that leads to his Unnaturally Longer Lifespan.

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