Hi Hsstein and thank you for coming to JustAnswer.com with your question.
The most common things that would cause weight loss as you describe would be cancer or hyperthyroidism
. Other causes can be infection (either an obvious infection, or one that is not immediately obvious such as HIV), different hormonal disorders, diabetes,
The first things that would be appropriate to workup would be the following.
Through family history including history of cancer, history of autoimmune
Complete blood workup including CBC, CMP, hormones such as TSH and Tumor markers.
Mammogram and Fecal Occult blood testing.
These are the things that would be the most common in your situation.
If all these turn out okay then further hormone and cancer testing should be done.
I hope all goes well.
If you have any follow-up questions feel free to ask them.
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