I usually think of healthy eating in terms of balance: fan against cai, hot food against cold food (whether using Chinese or Thai or Irani definitions), dal against bhat against sabji, etc. Obviously if even tiny quantities of some food would throw one's diet out of balance, it works out much the same as that food being forbidden, so that's of limited help.

I believe you're entitled to some steamed amaranth leaves with that quinoa bowl, btw.