Slander has a negative affect on health

When we are addressing a group of people,say a group of five and point
out that this person is good it is slandering.In my opinion we are in
one way telling that the other four are bad.In Punjab when a lady
praises her daughter,she in fact wishes to say that her daughter in
law is bad.So,I feel that slander and praise are the two sides of the
same coin.About two decades ago one of my trainers remarked 'I have a
friend.He is a Sardar.But he is a very nice man'.Was it a word of
praise?
How difficult to escape the vice of slandering!!