( ( The calorie ) ( ( ( is often ) ( associated ( with ( ( food and ) dieting ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN calorie)) (VP (VBZ is) (ADVP (RB often)) (VP (VBN associated) (PP (IN with) (NP (NN food) (CC and) (NN dieting))))) (. .)))
The calorie is often associated with food and dieting.
(ROOT (S (NP (NP (DT The) (NN energy) (NN content)) (PP (IN of) (NP (NNS foods)))) (VP (VBZ is) (ADVP (RB often)) (VP (VBN expressed) (PP (IN in) (NP (NNS calories))))) (. .)))
The energy content of foods is often expressed in calories.