[dreig]

You may attempt to apply the same analogy to drinking water, and see that it doesn't work. If you drink as much as you want, then you'll probably drink too much (with whatever negative consequences arising as a result). But, except for some extreme circumstances, I don't think people drink much more than is necessary to quench their thirst.

That is your conclusion might still be correct, but it doesn't follow from the analogy with eating.

[Zababa]

The thing is, the experience of drinking water has not changed much compared to before. However, if you take all beverages, you'll see that lots of people drink too much soda, and it's not to quench their thirst.

[RandomThrow321]

Water has changed dramatically. Think of all that goes into modern sedimentation, filtration, and disinfection - not to mention treatments for hard water or additives like fluorine. The taste is better because of the mineral content, and we can even add carbonation!

[Zababa]

That still doesn't make it a superstimulus. The difference is not that big in terms of stimulation.

[guzey]

Is drinking modern water a superstimulus like modern junk food from my analogy is?

[cardine]

You are conditioned to overeat because your body can store the excess energy in the event of future needs.

The body is expecting such a future need as in our past there were often periods of food scarcity. Since in our modern society this food scarcity doesn't exist, the body overconsumes, preparing for a future that will never come.

We do not have such a mechanism for storing infinite water, so we do not crave an overabundance of water.

I think you are thinking about sleep on the wrong axis. It is not whether it is a superstimulus; it is whether your body can store an abundance of it for a future anticipated need.

I would argue in this case, sleep is much more like water than food in this way in that there is a very small amount of sleep (possibly zero) your body can effectively stockpile.

[RandomThrow321]

Why is sleep a superstimulus but water isn't?