What nutrition deficiency is this?

When I go days or weeks without consuming rice or pita bread, my inner mouth begins to feel sandy and damaged, as if the skin is decaying or peeling off, and I know it is a nutrition deficiency but since there are so many different nutritions in rice and pita bread, I have no idea what deficiency it is.

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9 mo
It was a folate or a vitamin B9 deficiency, rice is enriched with folate in North America, which is why the white rice protected me when I included it in my diet, they also enrich white rice with vitamin B1 in the English speaking west, which is another reason the rice helps Asians lose so much body fat.
What nutrition deficiency is this?
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