Healthy food's down around a pound (5)
I believe the answer is:
salad
'healthy food's' is the definition.
(I've seen this before)
'down around a pound' is the wordplay.
'down' becomes 'sad' (I've seen this in another clue).
'around' indicates putting letters inside.
'pound' becomes 'L' (the pound sign is based on an L).
'a'+'l'='al'
'sad' going around 'al' is 'SALAD'.
(Other definitions for salad that I've seen before include "One may well be green" , "Green, potato, Russian or Waldorf?" , "Mixed food" , "vegetarian dish" , "Cold dish of vegetables or fruits" .)