I had my first experience in a far infrared sauna recently. It is a sauna that is cooler than the older saunas, it only reaches 110F to 150F. The difference is that this sauna opens up the insulin receptors next to skeletal muscles. The end result: you burn as much as 350 calories in a half hour treatment.
So, just to make sure the claims were true, I logged my blood sugar before going in. I was at a post-prandial peak of 170. After thirty minutes, I rushed out and measured again. Still 170. Hah, I thought, just another false claim about lowering blood sugar and burning calories.
Yet, as I cooled off on the way home, I started getting REALLY hungry. By the time I got home, made a dive for my glucose meter, and measured my blood sugar, it was 125. That was less than 10 minutes after a reading of 170.
So, from my tests, the claims of burning calories are true for Far Infrared Saunas. You can buy a good one for about $2500. I don't know if it is practical to use it daily, but it would certainly be good for not only blood glucose, but for toxic waste removal and skin toning. I think they are the next big thing for diabetes.