What is the advantage of using ATP as a common energy source? Another way of asking this question is, Why is ATP an advantage over using a bunch of different food molecules? For example, instead of just having a Na+/K+-ATPase in a cell, why not have a bunch of different ion pumps each driven by a different food molecule, like a Na+/K+-glucosase (a pump that uses glucose), a Na+/K+-sucrase (a pump that uses sucrose), a Na+/K+-fatty acidase (a pump that uses fatty acids), and so on?