Fasting makes her lazy and causes her to lose weight; can she not fast?

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Check below answers in case you are looking for other related questions:
She lost a lot of weight due to illness; is it permissible for her not to fast?
What is the sickness which permits a fasting person to break his fast?

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She lost a lot of weight due to illness; is it permissible for her not to fast?
What is the sickness which permits a fasting person to break his fast?

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