We had a holiday a couple of months ago in Japan. Fed up with sticky rice and lotus root in all its forms, we cracked in Tokyo and found a curry restaurant. This is quite a big thing in Japan, with endless options.
Base curry. About 20 additional things you can add. Five quantities of rice, and heat level.
So I had seafood (tick), no additional options (tick), standard quantity of rice (tick). Which left a choice of heat level. This went from 1 to 20. 1 was base level. I chose 5, reckoning that would be a bit hot.
Now I can take heat. But a 5 was right on the hairy border of heat. In the UK, where you are never more than a few miles from an Indian restaurant, anyone having a Vindaloo is worthy of respect. Well a 5 was way, way beyond Vindaloo heat, and at the level where you just shovel, and under no circumstances touch the water or beer until you have finished.
Now bear in mind that the heat index went up to 20! We joked that anyone ordering a 20 would be issued with a health warning, and an ambulance ordered to take you to hospital!
I have to say that a Japanese lady on an adjacent table ordered a heat level 6, and ate it like it was nothing to write home about. Respect.