It should be noted that many of these myths actually do hold a grain of truth in them
It is unlikely that this statement is true as research shows that a person who has a father who is suffering from hair loss, also has a significantly large chance of getting hair loss than someone whose father has a full head of hair. This statement does have some validity in that it will increase the likelihood of baldness for the person who has the grandparent who is bald, but it is not limited to the mother's father. The number one genetic factor in hair loss is the Androgen Receptor gene and is always inherited from the mother's side, and there is a 50% chance that a person shares the same X chromosome as his maternal grandfather, thus it could have come from either grand parent.
This notion could have arising due to cholesterol being one of the base components for which the body manufactures DHT. Although in modern times the link is not their, in ancient times it was likely that the more intellectual in society had better access to food and thus more likely to be bald. Another possibility that people attempted to offset the problem of hair loss by working on their intelligence.
this is not true, what is happening is that hats are causing hair to bread and split ends to form. Also the hat many have a knock on effect which could cause hair loss. This is because they are often not washed so could lead to a dirty scalp and contamination which could cause hair loss