Proponents of Metabolic typing claim that each person has a unique metabolism, and that therefore the nutrients which are appropriate for one person may be inappropriate for a second, and detrimental for a third.
Metabolic typing claims to use common visible symptoms related to the skin, eyes, and other superficial parts of the body to assess different aspects of a person's metabolism and categorize them into broad metabolic types. In addition, some proponents of metabolic typing use tests such as hair analysis to determine a person's "metabolic type".
A number of somewhat different "metabolic typing" diet plans are currently marketed. The validity and effectiveness of metabolic typing have not been established.
Read more about Metabolic Typing: Background, Effectiveness, Metabolic Therapies