( ( Despite ( ( their avoidance ) ( of ( eating ( at ( all costs ) ) ) ) ) ) ( , ( ( ( ( ( they ( ( are often ) ( obsessed ( with ( ( food and ) ( its ( calorie content ) ) ) ) ) ) ) , ) and ) ( this ( dominates ( their lives ) ) ) ) . ) ) )
(ROOT (S (PP (IN Despite) (NP (NP (PRP$ their) (NN avoidance)) (PP (IN of) (S (VP (VBG eating) (PP (IN at) (NP (DT all) (NNS costs)))))))) (, ,) (S (NP (PRP they)) (VP (VBP are) (ADVP (RB often)) (VP (VBN obsessed) (PP (IN with) (NP (NP (NN food)) (CC and) (NP (PRP$ its) (JJ calorie) (NN content))))))) (, ,) (CC and) (S (NP (DT this)) (VP (VBZ dominates) (NP (PRP$ their) (NNS lives)))) (. .)))
Despite their avoidance of eating at all costs, they are often obsessed with food and its calorie content, and this dominates their lives.
(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.