The main objectives of this study are:

• to assess the concordance of body composition measures between two bone densitometry devices: the STRATOS by Diagnostic Medical Systems (DMS) and the Hologic QDR 4500 A by Hologic inc.
• to assess the concordance of body composition measures between two bone densitometry devices: the STRATOS by Diagnostic Medical Systems (DMS) and the Hologic HORIZON A by Hologic inc.

The secondary objectives of this study are:

• the assessment of the consistency of body composition measurements at local level (arms, trunk, legs) between the Stratos and Hologic 4500 A,
• the assessment of the consistency of body composition measurements at local level (arms, trunk, legs) between the Stratos and Hologic HORIZON A,
• Monitoring the evolution of body composition in patients receiving at least two evaluations of DXA Hologic QDR 4500A on: patients treated for obesity or anorexia nervosa, sports people and other patient with prescription DXA and the assessment the consistency of body composition measurements in terms,
• Monitoring the evolution of body composition in patients receiving at least two evaluations of DXA Hologic HORIZON A on: patients treated for obesity or anorexia nervosa, sports people and other patient with prescription DXA and the assessment the consistency of body composition measurements in terms.

Inclusion Criteria:

• The patient must have given his/her informed and signed consent
• The patient must be insured or beneficiary of a health insurance plan
• The patient is referred by a doctor for the performance of an osteodensitometry examination or sportsmen coming through a protocol where the nuclear medicine department is the investigator center

Exclusion Criteria:

• The patient is pregnant or nursing
• The patient is unable to sign or refuse to sign the informed consent
• The patient has a coronary stent or metal sutures in the heart
• The patient has any type of metal objects in the body such as an artificial joint, a pin or a metal plate
• The patient has a pacemaker or defibrillator
• Patient weighing more than 200 kg or more than 2 meters high by 65 centimeters wide
• The patient is using an insulin pump or with insulin-necked
• The patient has undergone X-ray examination using a contrast medium such as barium in the previous seven days visit,
• Patient who underwent an examination using x rays in the 15 days preceding the visit
• Patient suffering from generalized edema