[Health effect] Rhizoma Drynariae is a nourishing food for strengthening kidney and waist. People often use it to treat kidney deficiency, low back pain and chronic diarrhea. Bone ballast tonic, dried rhizome of Polypodiaceae plant Quercus, etc. Bitter and warm in nature, entering the liver and kidney meridians. It has the effects of tonifying kidney, relieving pain, promoting blood circulation and strengthening tendons, and is often used to treat diarrhea due to kidney deficiency, rheumatalgia and lumbago due to kidney deficiency. "Herbal Zheng Zheng" said that it can cure "exogenous rheumatism, causing weakness and pain in both feet". Materia Medica holds that it can treat low back pain, joint pain, diarrhea, nocturnal emission and proctoptosis, while journal of traditional chinese medicine in Sichuan records that it can "dispel dampness and dredge menstruation". Pig's loin, that is, pig's kidney, is salty and flat, which is beneficial to strengthening the waist and kidney: it is often used to treat lumbago due to kidney deficiency, nocturnal emission, deafness due to kidney deficiency in the elderly, etc., which was called "old man's kidney deficiency" by Meng Xi, a famous doctor in the Tang Dynasty. [Dosage and cooking method] Every time 1 waist block, 6 bags of Rhizoma Drynariae. Wash and remove the pork tenderloin first, and remove the middle fascia. Then grind Rhizoma Drynariae into pork loin, tie it tightly with thread, cook it in clear water, and eat it with soup.