ObjectiveTo investigate the effect of hot spring baths on human immune function by analyzing the changes of immunoglobulins and complements in serum of residents after hot spring baths in order to provide a theoretical reference for the therapeutic effect of hot spring bathing.

MethodsAfter physical examination, 421 volunteers from five hot spring areas with three types of hot springs(temperature type hot springs, metasilicic acid type hot springs, and warm mineral spring type hot springs)in Guizhou Province were selected as the subjects. Under the guidance of professionals, the volunteers took a hot spring bath with the whole body immersed for four weeks, once a day, 5 times a week and 40-50 minutes each time. Finally, 311 volunteers completed the standard bath required by this study. The transmission immunoturbidimetric method was used to determine the content of immunoglobulins reflecting mucosal anti-infective immunity(IgA), anti-pathogenic microorganisms(IgG), recent infections(IgM)and the level of important immune effect factors(C3, C4)in the serum. Paired T test was used to compare the changes of serum immunoglobulin and complement before and after the hot spring bath therapy.

ResultsBefore the hot spring baths, the content of serum IgG, IgA, IgM, and complements C3 and C4 was(12.169±2.358)g/L, (2.285±0.891)g/L, (1.430±0.660)g/L, (1.224±0.186)g/L, and(0.257±0.073)g/L, respectively. After the hot spring baths, the content of serum IgG, IgA, IgM, and complements C3 and C4 was(12.769±2.984)g/L, (2.397±0.909)g/L, (1.497±0.715)g/L, (1.242±0.169)g/L, and(0.266±0.074)g/L, respectively.Comparison of results of different types of hot springs showed that warm mineral type of hot springs and metasilicic acid type of hot springs could significantly increase the serum levels of main immunoglobulins IgG and IgA(P < 0.05), while water temperature type of hot springs could increase the serum IgA content of the population(P < 0.05), but the effect on IgG was not significant(P > 0.05). Compared with before the bath intervention, the level of complement C4 in the serum increased in the population after the intervention of metasilicic acid type of hot springs and water temperature type of hot springs(P < 0.05).

ConclusionHot spring bathing can enhance the body's humoral immune function. Given that IgG is the most important anti-pathogenic microorganism antibody in body fluids, the result suggests that metasilicic acid hot spring and warm mineral hot spring are better than pure water temperature hot spring in terms of improving the body's humoral immune function.