Review on Japanese Articles of Spa's Health Promotion Effects in past 20 Years

Abstract

The studies on spa's health promotion effects on healthy or slightly unhealthy persons published in past two decades in Japan have been reviewed. Multidimensional findings from these studies have suggested that the spa resort using may have the effects of increasing and retention of skin and body temperature, improving peripheral circulation function, lowering blood pressure, improving gastrointestinal hormones secretion and increasing gastric mucosal blood flow, bettering metabolism, regulating the function of immune system, regulating the balance of autonomous nervous and internal secretion systems, relieving stress and relaxing, improving the quality of life (QOL), relieving the symptoms of those who are slightly unhealthy, promoting physical strength and fitness, promoting the well-being of the aged, reducing medical expenses of individuals or the community, keeping skin in good shape and restraining the skin's aging.
Of the 58 papers reviewed, the studies of hot spring bathing effects on increasing and retention of skin and body temperature, improving peripheral circulation function and lowering blood pressure were the most in numbers (12 papers, 20.7%), and then the studies of relieving the symptoms of those who were slightly unhealthy (10 papers, 17.2%). Case-control studies (26 papers, 44.8%) were the most used study designs, and then the clinical observation (20 papers, 34.5%). No findings from any one study reviewed in this paper showed that the spa resort using had definite evidence of health promotion effects. Probable effects were suggested from 32 studies (55.2%), but findings from the rest ones (26 papers, 44.8%) showed little evidence to support this consideration. Recently randomized controlled trials (RCT) had been used in studying the health effects of spa resort using in Japan and showed significantly better effects in the intervention group. However, the intervention methods used in the studies were comprehensive health education combing the instructions in appropriate ways of hot spring bathing and education on lifestyle and exercise. It was difficult, if not impossible, to separate the effect of hot spring bathing alone from the combination. The outcomes as effects used in the studies were blood profile, physique and other non-specific items. It may be also difficult to design and carry out a near perfect RCT study on the health promotion effects of spa resort using in field in the future. However, based on experience from past studies it is practicable and important to purse better epidemiological methods such as randomizing and crossover design. On the other side, as specific readers can be influenced marvelously by one book, the health conditions of users may be improved greatly and continuously by some spa. While evidence-based health care places emphasis on RCT, it is also extremely important to inspect the health promotion effects of spa using systematically and rapidly from the viewpoint of narrative-based health care.