[Theory] Devil fruits cause age to slow down greatly

[xxSasukEkUnxX]

quick thought:
All admirals are well over the age of 50, and still have black hair, no trouble moving, to the point where they can still be considered "in their prime"

now, let's take a look at sengoku pre timeskip

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black hair
post timeskip

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gray hair
he could've extracted his devil fruit after resigning from the marines

 

[Twin Steps]

No, don't think so

 

[YowYan]

never seen that grey-haired Sengoku...where did you get this from?

 

[Cartera]

quick thought:
All admirals are well over the age of 50, and still have black hair, no trouble moving, to the point where they can still be considered "in their prime"

now, let's take a look at sengoku pre timeskip

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black hair
post timeskip

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gray hair
he could've extracted his devil fruit after resigning from the marines

you know to extracted one's devil fruit you have to died. also ones the user died they grow back

 

[Jin Hayami]

Or it could be the stress.

 

[Punk Hazard]

He probably just aged. 2 years can do a lot to a person.