Only temporarily. They remove water, which is almost immediately regained. Not only do these methods accomplish nothing permanent, but they may put a dangerous strain on the heart and circulation. The recently fashionable sauna baths are a good example. In a sauna, the body is exposed to high temperatures to induce violent perspiration. This is a shock to the body, in which the pulse rate may double. It can be as much of a jolt as sudden and violent exercise. True, they have been popular in Finland for a long time, but keep two things in mind: the Finns subject themselves to saunas over a lifetime, instead of suddenly beginning in flabby middle age, and they dash water on heated stones, producing a much more humid and more tolerable beat than the new American saunas, which are electrically heated and produce a very hot and dry air.