Cyanosis or necrosis of the fingers is an ischemic symptom of the upper extremity in the clinical picture of subclavian artery steal syndrome. The common ones are, in order of prevalence, intermittent dyskinesia, upper extremity weakness, pain and sensory abnormalities, and very rarely cause cyanosis or necrosis of the fingers. So what homework can we do in our diet? Adequate calcium given daily can make up for the loss of the mineral content of the bones. Among common foods, the richest in calcium are dairy products such as milk, yogurt, and ice cream. Not only are they high in calcium, they are also rich in phosphorus, another important mineral that the body needs. The calcium-phosphorus ratio in these dairy products is relatively moderate, allowing for the full absorption of calcium and phosphorus. Milk also contains proteins and lactose. If you drink 2 cups of milk (about 480 milliliters) a day, you will have enough calcium for an adult. Of course, since older people lose a lot of calcium, their calcium needs are even greater. In order to better absorb the calcium and phosphorus in dairy products, you should consume dairy products every day while often “sunbathing” to ensure that you “sunbathe” for about 1 hour a day, which will yield better results. Milk should be stirred constantly when heated to prevent calcium phosphate from being deposited, resulting in the loss of calcium and phosphorus; milk and food containing phytic acid, oxalic acid and dietary fiber will reduce the absorption of calcium when consumed at the same time, so the milk is not eaten with spinach, and should not be drunk with strong tea. In order to further increase the absorption of calcium and phosphorus in milk, vitamin A and vitamin D can be added to milk to become “compound milk”. Or add cod liver oil (containing a large amount of vitamin A and vitamin D) or vitamin A, vitamin D in ordinary milk, can also promote the absorption of calcium, phosphorus and so on. Another food that contains more calcium is animal bone broth. Moreover, bone broth also contains fatty acids as well as proteins, of which fatty acids include saturated and unsaturated fatty acids. Proteins, lipids and calcium are all important substances in bone formation, so drinking more bone broth is also helpful in treating necrosis of the femoral head. However, there are fewer calcium ions in bone broth, and the concentration of calcium is lower, so when cooking the broth, the bones are smashed first, which can increase the dissolution rate of minerals and proteins. Seafood, such as fish, shrimp contain more calcium, phosphorus, and calcium and phosphorus ratio is reasonable, is a high-quality source of calcium and phosphorus, so eat more seafood, the femoral head necrosis patients have great benefits. When consuming fish and shrimp, choose the appropriate cooking method and eat with shrimp skin, because these ingredients contain more calcium.