There are no instant ways or methods to lose weight. Generally, weight gain is seen post pregnancy (which is physiological/normal), sedentary lifestyle, increased calorie intake, and in some cases due to hypothyroidism. There are no shortcuts to weight loss and do not fall for the marketing strategies. Sauna exposes a person to dry heat and wet heat alternatively and makes him/her to prespire, to be more precise, it is just like you sweat when there is a change in temperature and humidity. Prespiration is a response given by the body to cool itself when you are exposed to hot and humid weather. Do you lose weight through prespiration or sweating and is it a permanent weight loss, think about it? Sauna is more useful in cold countries where people do not sweat and methods like sauna will have a soothing effect in cold weather. The only benefit that you will have through Sauna in a country like India is muscle relaxation due to the exposure to heat, which can be acheived by warm water bath. Please be careful if you have conditions like arthritis while being exposed to heat or methods of treatments that are hot, which might aggravate your condition.