Brief Answer:
Poor oral hygiene is most common cause

Detailed Answer:
Hi

Thanks for writing in.

There can many reasons for yellow tongue and bad breath such as:
- poor oral hygiene that results in food build up with bad breath
- antibiotic use that results in imbalance of microbes
- prolonged use of mouthwash may also cause yellow tongue as it contains some oxidizing agents
- Jaundice which effects eyes and skin along with tongue

You need to maintain good oral hygiene and use tongue cleaner regularly for cleaning your tongue. Both of your symptoms indicate towards poor oral hygiene.
Consult your dentist and go for regular cleaning followed by proper oral hygiene maintenance.

Hope I answered your query

Wishing you good health

Kind regards
Dr. Neha Sumra

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