Hotter Hot Tub Water Poses Increased Fainting Risk

Hotter water in hot tubs poses increased health risks from fainting, Mayo Clinic researchers report. Mayo Clinic heart researchers had six subjects soak in 104 degree water (the current recommended temperature for hot tubs) and 106.7 degree water for 21 minutes to see if hotter water caused any ill effects.

They concluded that the higher temperatures posed little health risk from heart or circulation problems. But they found that when the subjects stood up to exit the tub, systolic blood pressure dropped dramatically, nearly twice as much in the hotter water compared to the 104 degree temperature. The result is less blood flow to the brain, which can cause fainting, which in turn might lead to injury by falling or by drowning. The authors point out that in an earlier study 36 hot tub deaths, 25 were found to be caused by drowning.

Thomas Allison, Ph.D., a cardiovascular disease specialist at Mayo Clinic, says the problem can be prevented by limiting time in the hot tub to 10-15 minutes, by keeping the water temperature no more than 104 degrees, and by emerging slowly from the water. "If there are steps, get out and sit on a step until your head is clear. If you do feel dizzy, lie down and elevate your feet." Their report appeared in the September issue of the journal Aviation, Space and Environmental Medicine.


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