Hi, Morwen. The Snopes essay mentions Dove and Dial. Other people have mentioned Ivory. Dial is surely a detergent, not actually a soap. Ivory is soap. Dove? I'm not sure.

So if the chemistry of the product doesn't matter, maybe what's affecting people is the perfume. Maybe the fragrance keeps people from sleeping too deeply and letting their muscles stagnate.

My husband has a keen sense of smell. One night I tried cooking food overnight in the slow cooker, and he announced the next morning that he woke up again and again, smelling the darn food. That was the end of that approach to cooking.

One thing's for sure - this is one cure where there's very little risk involved, so why not try it?

Bobert, just don't let the bar slip out of the bed where you might step on it when getting out. That's the only risk I can think of.