My stress system runs hot — I'm the classic reactive type who wakes up already braced. I found a trial that paired Lactobacillus helveticus with Bifidobacterium longum and tracked self-reported stress over 30 days, and decided to test the idea on myself while also doing five minutes of slow breathing before bed. I know the human trials are small and I might just be a placebo responder. But my logged morning-tension score moved from a 4 to a 2 over the month, and it crept back up the week I ran out and got lazy about the breathing. That little natural experiment told me more about my own pattern than any study did.