1. Quench thirst: Both egg shells and hawthorn contain a certain amount of water, which can supplement the water needed by the body and quench thirst.

2. Promote digestion: Egg shells contain a lot of calcium, which helps to promote intestinal peristalsis and digestion and absorption. Hawthorn can also promote the digestion of food and relieve the symptoms of indigestion.

3. Calcium supplement: Egg shell is a good source of calcium, and the water cooked with it is also rich in calcium, which can supplement the calcium needed by the human body and help prevent calcium deficiency such as osteoporosis.

However, it should be noted that egg shells and hawthorn are not medicinal ingredients, and their efficacy and function cannot be confirmed or recognized. Before drinking this drink, you should be moderate, not excessive, especially those with special diseases, and consult a doctor or dietitian.