LDL 4.22mmol/L is not appropriate for normal levels and requires intervention as soon as possible. The normal reference level for LDL is less than or equal to 3.4mmol/L, reaching 3.4 to 4.1mmol/L is a borderline level, and if it exceeds 4.1mmol/L it is an elevated level. Therefore, 4.22mmol/L is not a normal level. In this case, we need to actively improve our lifestyle, including avoiding oily and high-salt foods, eating more fresh fruits and vegetables, quitting smoking and drinking, and maintaining a certain intensity and frequency of aerobic exercise, such as jogging and cycling. If the above lifestyle interventions are still unsatisfactory, statins such as atorvastatin, ezetimibe, and colesevelam can be taken under the guidance of a doctor to assist in lowering cholesterol. It is recommended to seek medical advice as soon as possible.