I am 57 years old.
For the past 10 years my hair has become a lot thinner. Does anybody know a cure from this?

As you have specfied your age i can say age can be one of the factor of hair loss, or if your consuming any medication it's side effect can be hair loss.
Primary thing you can di is oil your hair daily, need to take balanced diet, drink lots of water. take a good sleep, try to avoid stress or tension as it can e one of the factor of hair loss.