I think I've developed a sensitivity to cooked tomatoes. My symptoms were all digestive-rated -- nausea and diarrhea. There did not seem to be any histamine-related symptoms, like hives, sneezing, or difficulty breathing.
I googled food sensitivity and found some good sites that explained things.
Regarding the salads, you might try eliminating ingredients one at a time to see what causes the problem. Although since it's not a regular occurrence that might not work.
I used to have a similar problem with salads and it turned out the problem was the Newman's Own Italian dressing. I don't know exactly what ingredient caused the problem.
- Gray 2010 carbon WSD road bike, Rivet Independence saddle
- Red hardtail 26" aluminum mountain bike, Bontrager Evoke WSD saddle
- Royal blue 2018 aluminum gravel bike, Rivet Pearl saddle
Gone but not forgotten:
- Silver 2003 aluminum road bike
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