Controlled exposure to heat — through saunas, steam rooms or hot tubs — is gaining attention for more than relaxation. In a recent appearance on CBC Radio’s The Dose, environmental stress researcher Dr. Stephen Cheung outlines how regular passive heat can deliver lasting benefits for cardiovascular and brain health.
Dr. Cheung has studied environmental stress since beginning graduate work in 1991. Over three decades he has researched how heat and cold affect human physiology and performance, advising elite athletes, firefighters and military personnel on operating safely in extreme conditions.
While extreme heat can impair performance or cause heat illness, Dr. Cheung explains that planned, passive heating has different effects. Repeated sessions of safe heat exposure have been associated with improved blood vessel function, lower stroke risk, and potential reductions in the risk of neurodegenerative conditions such as dementia and Alzheimer’s disease.
One primary mechanism involves increased pulsatile blood flow through vessels. This elevated shear stress stimulates the endothelium — the inner vessel lining — to release relaxing factors, including nitric oxide. The result is