Have my dreams come true? Unfortunately, not quite.
Yes, hot baths burn calories but there are a few caveats. An hour in 104F water is a long time. And the calories burned don’t equate to exercise. However, baths may have other benefits that are harder to quantify.
Obsessing on the calorie burn can also obscure that not all calories have the same effect in our bodies.
Interesting as the physiological effects of passive heating are, they may be less promising for human health than the effects of taking up a calming ritual like sitting alone in water. Baths tend to be a rare time for reflection and disconnectedness, which are incomparably beneficial.
Baths Versus Exercise, a Study in Calories I The Atlantic