We had the same experience. When we first got our M2, I had no idea her white color and pale orange crest wasn't normal. Her diet at the time was the typical peanuts and seeds.
While searching the I-net hoping to find information on how to deal with an M2's bad behavior, I stumbled across this site. Not only did a I find out how to deal with the behavior issue, I learned what Too should be eating. Over time, I got her switched over to pellets, fruits, and some other misc. goodies she likes. Unfortunately, nearly 10 years later, veggies are still viewed as "poison."
An unexpected side benefit of an improved diet was that her coloring started to change to what it is today. Peachy, yellow and bright orange. Our daughters who only see Chucki every few months, say her colors are still improving even after all these years. A good diet is important.