Stacy sims cold water under 15 C harmful for women

Yes. Dr. Stacy Sims cautions that very icy water—below about 15°C—may be too cold for women because the sudden exposure can trigger severe vasoconstriction and shutdown. She says around 16°C (55–56°F) is cold enough to elicit the desired cold-exposure response while avoiding that severe constriction. 1

• 16°C (55–56°F: Sims says women can still get a dopamine response and other cold-exposure effects at this temperature, with less risk of severe constriction. 2
• Heat therapies: Sims says she prefers heat for women, noting that women generally respond well to heat and get better adaptations; she specifically mentions sauna and hot tub use. 3