Rickets is a systemic chronic nutritional disease caused by vitamin D deficiency leading to disturbances in calcium and phosphorus metabolism, which results in abnormal bone development. The main cause is a lack of vitamin D, generally related to feeding methods, the addition of cod liver oil, living environment, outdoor activity time, repeated respiratory infections, calcium deficiency during pregnancy, and the season of birth. It is generally recommended to routinely supplement vitamin D and cod liver oil after birth, have regular follow-ups, engage in appropriate outdoor activities, and during pregnancy, it is important to supplement with adequate calcium and vitamin D. Additionally, attention should be paid to children who have repeated respiratory and gastrointestinal diseases, as these can also affect the absorption of vitamin D and calcium and phosphorus. Thus, it is vital to actively prevent other diseases that may affect the absorption of vitamin D and to treat illnesses proactively when they occur.