1 Strict Jains don’t eat root vegetables such as potatoes, onions, roots and tubers, because such root vegetables are considered ananthkay. 2  Ananthkay means one body, but containing countless lives. 3  A regular vegetable such as cabbage has number of leaves and lives as could be counted by a layman.t is one of the most rigorous forms of spiritually-motivated diet on the Indian subcontinent and beyond. The Jain cuisine is completely vegetarian and also excludes onions, potatoes, brinjals and garlic, similar to the shojin-ryori Buddhist cuisine of Japan.