According to the books, a mage with five dots in life sphere could use Perfect Metamorphosis.
Perfect Metamorphosis: The mage can alter their own Pattern according to their wishes. They may assume any form they wish, free themselves from corporeal needs like hunger and become immune to all known diseases.
This can basically let a mage make themselves younger whenever they get too old, so why did Tremere and his followers choose to become vampires rather than just developing their life sphere?