Yes, you can swallow your own saliva during Jain fasting.

In Jainism:

• Swallowing natural saliva that forms in your mouth does NOT break any fast (upavās, bēsna, chauvihār, atthai, even nirjal).
• This is accepted in both Digambar and Shwetambar traditions, because saliva is produced by your own body (internal), not something you are “eating” or “drinking” from outside.

However, you should avoid:

• Deliberately creating extra saliva to reduce thirst (e.g., chewing anything, sucking clove/cardamom, mouth fresheners, etc.).
• Rinsing the mouth and then swallowing that water (this breaks a waterless fast).
• Sucking ice, stones, or anything that brings external moisture inside.

Essence:

• Normal, natural swallowing of saliva = allowed.
• Bringing or creating any outside liquid to swallow = not allowed.

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