Reverification of the Alkaline Hot Springs Efficacy on Arteriosclerosis using Changes in Skin Cholesterol Levels due to Mid-infrared Light Absorption Spectrum: based on Improved Analytical Methods and the Mathematical Model of Arteriosclerosis Develo

The efficacy of Yuda Onsen (Japan) for arteriosclerosis was tried to be reverified based on the change of the difference between the "peak" and "valley" of the absorption spectrum of cholesterol ester after bathing. The measurement principle of cholesterol ester is to irradiate the skin with light in the mid-infrared region and determine the cholesterol ester level of the skin from the absorption spectrum intensity. As a result of reverification of efficacy of Yuda Onsen against arteriosclerosis, the improved analysis method found that alkaline hot springs may have an efficacy on arteriosclerosis because bathing in alkaline springs contribute to the decrease in cholesterol levels.