To be or not to be naked in sauna?
The most reasonable and non-discriminatory rule is that in the steam room everybody can wear a swimming suit or be naked.
Neither way should there be any hegemony even if you are alone in the minority.
If swimming suits are soaked in chlorine water, however, they must be taken off because the warmth makes the toxic chlorine evaporate into the air to be inhaled by others. If you only go ice swimming, there is no need to take off the swimming suit in sauna.
The shy and those afraid of being naked can use a towel in sauna.
In Germany's many excellent spas one must be naked in sauna and sit on the benches on a towel, with their feet wrapped in it.
Going to sauna naked is of course healthier and more comfortable because the liquid flow enhanced by the heat is not impeded by of often tight swimming suits, and sweat can flow freely out.
Also ice swimming is more comfortable and healthier naked, without the cold water clinging to the swimming suit and strong fluid flow being able to take place freely.
Everybody should try nudity and see how quickly one gets used to. Of course, your own spiritual nudity freedom depends on your self-esteem, your image or your body, and cultural and sometimes even moral issues.
In the 17th and 18ty centuries Finland became famous in Europe for its farm and even village saunas where all classes, age groups and genders met each other as equals, naked. Without a doubt, this has had a nationally beneficial effect on the naturalness of body culture, and also socially. Unfortunately, Queen Victoria’s puritanism targeted e.g. nudity in sauna and reduced it.
E.g. the American hysteria about nudity comes from both this and Catholicism.
Numerous studies telling about the health effects of sauna are pro nudity. San Diego based health scientist/biochemist Rhonda Patrik, who also gave a lecture about the healthiness of sauna in Finland, has a thorough video lecture on the subject on her website (foundmyfitness.com). In Finland, she too, even though she is an American, fell in love with going to sauna by a lake and ice swimming.
I encourage all keepers of mixed saunas to allow free dressing in their saunas, with the exception of swimming suits soaked in chlorine.