ide ▁that ▁cannot ▁exist ▁in ▁vit ro . ▁ ▁N it rate ▁or ▁nit rite ▁( ing ested ) ▁under ▁conditions ▁that ▁result ▁in ▁end ogen ous ▁nit ros ation ▁has ▁been ▁class ified ▁as ▁" pro bably ▁car cin ogen ic ▁to ▁humans " ▁by ▁International ▁Agency ▁for ▁Research ▁on ▁Can cer ▁( I AR C ). ▁ ▁S od ium ▁nit rite ▁consumption ▁has ▁also ▁been ▁linked ▁to ▁the ▁trigger ing ▁of ▁mig ra ines ▁in ▁individuals ▁who ▁already ▁suffer ▁from ▁them . ▁ ▁One ▁study ▁has ▁found ▁a ▁correlation ▁between ▁highly ▁frequent ▁ing estion ▁of ▁me ats ▁c ured ▁with ▁p ink ▁salt ▁and ▁the ▁C OP D ▁form ▁of ▁lung ▁disease . ▁The ▁study ' s ▁research ers ▁suggest ▁that ▁the ▁high ▁amount ▁of ▁nit rit es ▁in ▁the ▁me ats ▁was ▁responsible ; ▁however , ▁the ▁team ▁did ▁not ▁prove ▁the ▁nit rite ▁theory . ▁Additionally , ▁the ▁study ▁does ▁not ▁prove ▁that ▁nit rit es ▁or ▁c ured ▁meat ▁caused ▁higher ▁rates ▁of ▁C OP D , ▁merely ▁a ▁link . ▁The ▁research ers ▁did ▁adjust ▁for ▁many ▁of ▁C OP D ' s ▁risk ▁factors , ▁but ▁they ▁commented ▁they ▁cannot ▁rule ▁out ▁all ▁possible ▁un me as urable ▁causes ▁or ▁ris ks ▁for ▁C OP D . ▁ ▁Production ▁ ▁Indust rial ▁production ▁of ▁sod ium ▁nit rite ▁follows ▁one ▁of ▁two ▁processes , ▁the ▁reduction ▁of ▁nit rate ▁sal ts , ▁or ▁the ▁ox id ation ▁of ▁lower ▁nit ro gen ▁ox ides .