This is determined by their genes. Manfred Kaiser, a researcher at erasmus University in Rotterdam, the Netherlands, believes that the aging effect caused by genes is similar to that caused by smoking.

Hormones in the human body are different. Everyone looks young when he is young or when he is old, which is a normal physiological reaction.

The maintenance and beauty of the day after tomorrow are auxiliary conditions, and some people can keep themselves from getting old through maintenance.

Living and working environment, mood and mentality, and health care also affect people's age.

Exercise can also change the way people look young or old.