Short read
Rainer Brenke published this review in Forschende Komplementärmedizin / Research in Complementary Medicine in 2015, volume 22, issue 5, pages 320 to 325, where it appeared as Editor's Choice. Brenke is an internist and specialist in physical medicine and naturopathy. He has published on the effects of sauna since 1979, with around 250 papers and 19 books, and has been an honorary member of the German Sauna Association since 2024. Among reviews written in German, it is the main reference on the topic.
The author argues that the preventive and therapeutic potential of the sauna is far from exhausted. The review covers resilience against common colds, cardiovascular prevention, pain therapy including fibromyalgia, stress prevention and type 2 diabetes. As a narrative review, it has no comparison group and presents no new figures of its own; its statements are the author's reading of the literature.
It appeared in a complementary medicine journal with less international visibility than the large medical journals. Part of the primary literature it cites comes from the International Sauna Archive and is hard to access, which makes the underlying evidence difficult to check.
The paper is a German-language overview of where the author sees potential, not a demonstration that the sauna prevents any of the conditions it covers. The claim that the potential is underused is an assessment. His honorary membership of the German Sauna Association is part of the context for it.