A lot of natural deodorants contain baking soda, which some people have a reaction to. it's the top ingredient in crappy Party.
I'm actually glad Kurt has loosened up his restrictions. The guy needs less stress and more fun in his life. But the whole SIBO thing is so shady. From what they said, Phase Two (week 5-8) is the "kill" phase, where they try to kill the bacteria in his gut causing him issues. So he's back to square one if he's stopping now. It makes no sense.
I'm not doubting it exists or that Kurt doesn't have it (though I believe his issues are more mental health related) but it's clear Sarah just used this to divert attention from her cultural appropriation fallout. She's a real piece of work. Who knows, maybe Kurt is realising where his issues are actually stemming from, and it's not the food so he's eating normally again.
Also wanted to add in this screenshot from her stories today. Sezzy time strikes again. No Sarah, you've only been on holiday for 1 week, not 2.