Is there any sideeffects or disadvantages of Suana belt?

Answer 1

Sauna belt will only cause you to sweat locally and sweating will cause water loss but this will be gained back as soon as you drink any beverage. There is no such thing as a "site" reduction, you must lose weight over the whole body. So there should not be any side effect other than a possible irritation from the belt/sweating, but nothing serious or dangerous.
The disadvantage is it's not going to do anything for you.