Although clinically effective, they are associated with significant metabolic side effects, including increased insulin resistance, impaired function of pancreatic -cells, and, finally, weight gain
"These products are either counterfeit or resold outside the approved supply chain - and both situations pose serious risks to patients' health." The company said it was taking steps to "combat the proliferation of counterfeit and unsafe products" including working with law enforcement, publishing warnings and trying to identify harmful online content
PMID: 21030672 | doi:10.1152/japplphysiol.00945.2010 Seiwerth S et al
Observational research can show association, not proof that sauna alone caused the outcome
Male Fertility In men, reactive oxygen species damage sperm membranes, reduce motility, and change shape, all lowering fertilizing ability
van Geel and Speeckaert, 2017)