The Healing Power of a Bath (and how it works)

There are a number of “fitness trends” out there that don’t mean a thing. From people putting butter on their bodies to drinking special tea — people will do just about anything to lose weight.  But new research found that one thing we already do can truly help lose weight: a hot bath.

Many cultures swear by the benefits of a hot bath it makes us relaxed, gets us in the mood (wink, wink). But only recently has science began to understand how passive heating (as opposed to hot and sweaty exercise) improves your health.

Loughborough University investigated the effect of a hot bath on blood sugar control (which is super important in fitness) and the number of calories burned. Participants were assigned to an hour-long soak in a hot bath (40 degrees Celsius) or an hour of cycling. The activities were designed to cause a 1 degrees Celsius rise in core body temperature over the course of one hour.

Cycling resulted in more calories being burned compared with a hot bath, but bathing resulted in about as many calories being burned as a half-hour walk (around 140 calories). The overall blood sugar response to both conditions was similar, but peak blood sugar after eating was about 10 percent lower when participants took a hot bath compared with when they exercised.

In fact, the bathers’ peak blood sugar levels after eating were about 10% lower than the peak blood sugar for the cyclists, which shows promise for using “passive heating” as a means of helping control metabolic disorders like type 2 diabetes.

The bathers also experienced an anti-inflammatory response similar to the effect seen in people after they exercise, which is also promising, since people with chronic disease tend to have chronic inflammation.

Passive heating for human health is a relatively new field of research, but some exciting results have emerged over the past few years.