Jains avoid root/underground vegetables mainly to practice ahimsa (non-violence) more strictly.

• Root vegetables require pulling the whole plant from the ground, which kills the plant and harms many tiny life forms living around the roots.
• Roots are believed to harbor a large number of subtle lives (nigodas); eating them is seen as causing more harm than eating above-ground plants.
• This practice helps minimize harm and keeps focus on spiritual discipline (especially during vows, holy days, and monsoon periods).

Note: both Śvetāmbara and Digambara traditions generally follow this principle, though exact dietary rules can vary by sect, region, and vow during special periods like Paryushan/Chaturmas.

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