Jennie: Start off slow, say 15 minutes at the most. Then you build up to close to an hour. I did sauna at the clinic I went to for 45-50 minutes, three times a week at 160 degrees. You have to work your way up to that, so you dont detox too fast. I felt SO much better. If you are not a regular in the sauna, take it s-l-o-w and get out if you feel weak or dizzy. Lucky, you have sauna to use. Good luck-