Jains can eat red lentils (masoor dal) in many traditions, but some families avoid them. That’s why you may have heard “Jains don’t eat red lentils.”

Main Jain principles behind this

All Jain food rules come from ahimsa (non‑violence) and sanyam (self‑control):

1. Avoid killing more living beings

- Root vegetables (potato, onion, garlic, etc.) are avoided because pulling them out kills the whole plant and many tiny lives in the soil. - Pulses/beans (including red lentils) are above the ground, so they are not root vegetables. But they still contain many tiny lives, especially when fresh or sprouting.

1. Fresh vs. dry pulses

- Fresh/green/sprouted pulses are considered to have more jiv (life), so many Jains avoid them, especially in Chaturmas, Paryushan, or on tithis. - Old, dry, unsprouted dal (including masoor dal) is usually considered less himsak, so it is commonly allowed in many Jain homes if cooked simply and used in moderation. ( jainknowledge.com)

Why some Jains avoid red lentils specifically

• Strict families (more common in some Digambar traditions) try to reduce all types of pulses, not only masoor.
• Some elders feel masoor dal is “heavier” or more tamasic, so they prefer moong/tuvar/chana instead.
• During Paryushan / Chaturmas / special vows, many people temporarily avoid all dals or at least reduce them for extra discipline.

So:

• Not a universal rule: Jain scriptures do not single out “red lentils” as forbidden like meat, eggs, honey, or root vegetables.
• Practice depends on:

- Your sect (Digambar / Shwetambar), - Your family’s tradition, - Any personal vows (vrat) you have taken.

If your family says “we don’t eat red lentils,” they are following a stricter form of ahimsa and simplicity, which is respected in Jainism.

You can read more about Jain diet and pulses here