The earliest citations of 'in the pink' are from the 16th century and, at that time, the meaning was 'the very pinnacle of something', but not necessarily limited to health. The earliest example that I can find of pink being used with that meaning is from 1597 Shakespeare's Romeo & Juliet, 1597:
Mercurio: Why, I am the very pinke of curtesie.
The earliest citation I've found for 'in the pink' is from Leigh's Kensington Gardens, 1720:
"'Tis the Pink of the Mode, to marry at first Sight: - And some, indeed, marry without any Sight at all."
The 'pink of the mode', i.e. the acme of excellence of fashion, was a common early usage and continued to be used throughout the 19th century.
Delilah Smith, Michigan, USA
About This Painting:
watercolor on 140 lb cold pressed watercolor paper
The finest quality watercolor were used in this painting.
Size: 9 in X 12 in (22.9 cm X 30.5 cm)
Price: $100 USD
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