Jāmīkand (or ratalu / suran / yam) is not eaten by Jains because it is a kand-mūl – a type of root / underground vegetable.

In Jain dharma, such foods are avoided mainly due to ahimsā (non‑violence):

1. Entire plant is killed

To take jāmīkand out, the whole plant is dug up and destroyed. In fruits or leaves, you can pluck and the plant still lives, but in roots the main life-base is taken away.

1. Many tiny living beings (jīva) are harmed

Around and inside root vegetables there are countless subtle lives (nigod, sūkṣma jīva). When the root is dug out, soil is disturbed and many small organisms are killed.

1. Anantkāy (multi‑souled) category

Traditional Jain texts describe certain roots as having forms of life where many souls are associated together, so eating them is considered more violent than eating normal vegetables.

1. Stricter practice of ahimsā

Both Śvetāmbara and Digambara traditions teach avoiding kand‑mūl (like potato, onion, garlic, jāmīkand, etc.) for those who want to follow a safer, less‑violence diet. Exact lists can vary by region and guru, but jāmīkand is generally kept in the “not to be eaten” group.

So, Jains don’t eat jāmīkand not because it is dirty or unhealthy, but because removing and eating it involves much more himsā than ordinary vegetables.