Being healthy means the same as being disease free(false).I want to know why this statement is false?

Health is defined as a state of complete physical, mental and social well-being and not merely an absence of any disease.

Physical health and mental health are inter-related. When a person can work hard, interact well with people, enjoy leisure and can adopt to changes and stresses of life, maintains personal hygiene, has a good appetite, then the person is in good health.