Cooking in 'lite' was something a model needed to watch, perhaps (9)

I believe the answer is:

waistline

'something a model needed to watch perhaps' is the definition.

'cooking in lite was' is the wordplay.
'cooking' indicates an anagram.
'in'+'lite'+'was'='inlitewas'
'inlitewas' is an anagram of 'WAISTLINE'.

(Other definitions for waistline that I've seen before include "Swine tail (anag.)" , "It goes round trunk" , "Girth" , "measurement" .)

I've seen this clue in The Telegraph.

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