I need a hot tub.
I think the kids could use one too.
In Hot Water
A. While there are plenty of common-sense reasons to keep people with childish judgment out of heat and water at any age, studies (mostly in Finland) have not linked careful sauna use to serious medical problems in healthy children. The chief injury risk to children seems to be scalding.
Whirlpool baths appear to be dangerous to children — and adults — chiefly as a drowning risk, especially if a strong whirlpool mechanism traps a small body. Another possible risk is bacteria in a whirlpool that is not properly maintained, but again, the risk is not age-specific.
A Finnish review article published in 2006 in The International Journal of Circumpolar Health noted that children in Finland were first taken to the sauna at an average age of 5 months. A single physiological study of healthy babies with an average age of 7 months found no harmful cardiovascular responses after a three-minute exposure. But the review also said that a sauna put bigger demands on a child’s circulatory regulation than on that of an adult, and it reported that a study of 20 children 5 to 10 years old found moderate hormonal changes. The review concluded that healthy children older than 2 could be allowed in a sauna with adequate adult supervision.
There were some caveats for children who had specific heart disorders, but a study of sauna-like heat as a treatment to dilate blood vessels in some very young infants with heart failure because of ventricular defects found benefits that avoided surgery in some cases.