She is suffering from lack of appetite.

她没有食欲。

《新英汉大辞典》

Symptoms include fatigue, lack of appetite and concentration, irritability and a feeling of helplessness.

假后综合症的症状包括感到疲惫、没有胃口、无法集中精力、易怒和无助感等。

youdao

Begin this dosage 20 days before treatment and continue during the therapy to reduce dryness of the mouth and lack of appetite.

治疗前20天开始服用。治疗期间继续服用可以减低口干与可增加食欲。

youdao

Fear coursed through me as I nibbled on breadsticks, protesting a lack of appetite.

WSJ: Escabeche: A Seafood Dish for the Fish-Phobe

Symptoms of swine flu include fever, lethargy, lack of appetite, coughing, runny nose, sore throat, nausea, vomiting and diarrhea, the CDC said.

CNN: U.S. prepares for possible swine flu epidemic as global cases rise

Symptoms of swine flu in humans are expected to resemble regular human seasonal influenza symptoms, including fever, lethargy, lack of appetite, and coughing, the CDC said.

CNN: CDC confirms 7 cases of swine flu in humans