Isovalerylglycine as biomarker for the predispositon for weight gain and obesity

A method of diagnosing the likelihood of a subject to resist high fat diet induced weight gain, the method comprising:

• determining the level of isovalerylglycine in a urine sample previously obtained from a subject to be tested, and
• comparing the subject's isovalerylglycine level to a predetermined reference value,
• wherein the predetermined reference value is based on an average isovalerylglycine level in urine in a control population, and
• wherein an increased isovalerylglycine level in the sample compared to the predetermined reference value indicates an increased likelihood to resist high fat diet induced weight gain.