[evilturnip]

100% agree. I've found no theory as to what correlates with my particular issues: hives and elevated heart rate when consuming processed food/gluten/I don't know what over a long period and also difficulty sleeping. If I go pure low-carb, I'm fine, even if I consume large amounts of sugar. However, stress can also induce it even if I am eating properly. Additionally, evaporation of sweat also causes it in certain cases.

Nobody seems to have any idea what the issue is, but I've learned to manage it by controlling diet and stress basically. I'm still not 100% why/how it happens.

I've learned that these sorts of issues may be something science will never figure out for me since they focus on populations rather than the individual. I expect in 10 years some studies at some point will start isolating some of these triggers as they become more prevalent. I've talked with a few people who've had similar issues.