What is the relation between people's inability to notice having a brewing disease and business predicting turmoil in the future hence going for the diet?

A bad one. What's the insight here? If a body were a nation-state, it'd be a totalitarian hellscape where life is cheap, individuals exist only to support the collective and some populations are invaders to be exterminated.

I'd call it a complex system. It's entirely possible to have a component in a system that may disrupt the whole system in a whole new, unpredictable way. Just like some sort of asymptomatic tumor which breaks the whole body once it metastasizes.

Yes, and as I don’t want metaphorical chemotherapy for the country I’d prefer we chose a different metaphor. An analogy shouldn’t just be some strained parallels, it should lead us in useful and not destructive directions.

Oh, fair enough. Something surgical would be best :)