Acupuncture takes the lower region of the thumb as “the mount of thumb”. And they have taken the outer half of the thumb as the zone of reflecting the condition of respiratory organs. The inner half of the thumb is taken as the region of reflecting the condition of the stomach, spleen, and the large intestine.
You may not feel sick with your stomach and the large intestine. However, if the color of the mount of the thumb shows purple, or in the beginning phase of getting cold, if the mount of the thumb sags and you feel headache, you should check whether you are infected with the disease of gastroenterology.
If you rub this region and feel good, it represents that region is the region of reflecting the condition of the stomach and the large intestine. It is the mirror of reflecting the health level of the internal organs.