Older people can increase their immunity by eating foods such as beans and meat containing high quality protein, milk and its products containing calcium, and black fungus and purple cabbage containing iron. 1. The quality of protein for the elderly should be higher, and it is recommended that quality protein should account for 50% of the total protein intake. Beans are rich in protein, eggs, dairy (milk), meat, including poultry, livestock and fish muscle is also rich in protein, amino acid composition is also more balanced, while the nutritional value of animal protein is generally better than plant protein. 2.800~1000mg/d can basically meet the needs of the elderly to maintain bone health, milk and its products are the best source of dietary calcium, fresh milk calcium content between 1000~1200mg/L, skimmed milk powder is a little higher. Soybeans and their products are also a good source of calcium, with tofu containing 110~140mg/100g of calcium. 3. As the elderly dietary quality and absorption rate may be reduced, but also need to supplement the corresponding iron, such as black fungus (dried), nori (dried), duck blood and other foods per 100 grams of iron content of 97.4mg, 54.9mg, 30.5mg respectively. In addition, the elderly to increase immunity, you can carry out regular exercise, such as walking, playing Tai Chi, etc. If the immunity is still low or accompanied by underlying diseases, you need to use immune-enhancing drugs under the guidance of a doctor.