How does high self-esteem and a positive outlook affect a person's health

Self-esteem is a measure of what we believe about ourselves, not what others think of us.
Self-esteem is directly linked to how we evaluate our interactions on a day to day basis, so the stress that we feel is very often tied to whether we believe we're "enough". Stress is a major factor in a variety of physical ailments; it directly affects blood pressure and the immune system. 

Self-esteem also is a direct influence on a person's interest in taking care of themself. If I believe that I'm [email protected] then it naturally follows that there isn't much point in eating right, exercising, attending to my spiritual health, having friends, ... People with low self-esteem are much more likely to be chronically depressed

Self esteem isn't measured on how much people believe in us its on how much we believe in ourselves. the high self esteem directly affects your blood pressure and you immune system and also affects the way a person takes care of themselves. 

They need to know because sometimes they have a symptom