Brief Answer:
Might be nutritional deficiency or due to side effects of medicine

Detailed Answer:
Hi,
Thank you for posting your query in Healthcaremagic.com.
This is Dr. Swarnava Dattagupta answering your query.

I understand your concern.
Tastelessness and nausea are common symptoms of many disorders, starting from nutritional deficiencies, side effects of certain drugs for hypertension, diabetes etc, gastroesophageal reflux disorder or indigestion, chronic smoking, chronic long standing diseases like anemia, tuberculosis, tumours etc.
You are hungry, so your appetite is fine. The problem is mostly in the metabolism perhaps or due to nutritional deficiencies.
In such cases, I generally advise the following-

Take plenty of water, green leafy vegetables and small frequent meals; avoid fatty and junk food.
Exercise regularly.
Take pantoprazole-domperidone combination for 15-20 days.
Get a blood test for complete blood count done.
If you are taking any medicine for comorbidities like hypertension, diabetes etc which are known for side effects like nausea, vomiting, gastrointestinal intolerance, consult your doctor for change of dosage or medicine if required.
Multivitamin syrup or tablets for 1 month.
Quit smoking and alcohol if any.

You can consult these with your treating or family doctor.
Get back to me with the reports or follow up after 15 days.

Hope I have answered your question.
If you have any further questions I will be happy to help.
Regards.

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