Short answer: Yes, many Jains eat groundnuts (peanuts). They are seeds, not root vegetables, so in many traditions peanuts are permitted as a lower-hinsa option compared to root vegetables.

Important caveats:

• Some Jain communities avoid groundnuts, especially during periods of stricter vows (like Paryushan/Chaturmāṣa), because peanuts grow underground and are considered more hinsa to harvest.
• Practices can vary between Shvetambar and Digambar households and even from guru to guru. Always follow your family or guru’s guidance.

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