There is a comprehensive list of foods that are optimum for each blood type and neutral and difficult. How Blood Types Are the Keys to Unlocking Your Personality by Peter Constantine. Your Type both start to describe how each blood type has a personality type associated with each blood type. This book goes into greater detail. Although we are more complex than this, this is a good place to start.
Some people seem to also fit their astrological profile.
In addition we also can be described by a variable percentage of the 9 enneagram types. This tells me that we are definitely more vast than any simple system. However, I believe that healing the blood type personality first could be of tremendous benefit. I'll rate this book and tell you more, after I get this book and evaluate it. That Promote Health and Healing .