Wasabi and radishes and mustard have a different chemical mechanism from peppers for their spice. I had a friend who grew up in India, and has basically no regard for capsaicin, over for dinner one night. We had some radishes out of our garden, and some of them were definitely on the hot side so I warned her. She scoffed and bit off half a good sized radish. She was soon downing iced tea to wash it away and said, oh my god, is that what spicy food is like for you? But capsaicin is oil based and doesn’t wash away so easily.

The morning necessity is probably caffeine.

But capsaicin is a neurotoxin, and high enough doses absolutely can be dangerous and even fatal. The pain involved long before those doses are reached keeps most sensible people safe.