Pasty and doughnut diet for Americans? (5)

I believe the answer is:

paleo

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'diet for americans?' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'pasty and doughnut' is the wordplay.
'pasty' becomes 'pale' (synonyms).
'and' is a charade indicator (letters next to each other).
'doughnut' becomes 'o' (letter resembling a doughnut).
'pale'+'o'='PALEO'

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