This study propose to compare the effectiveness of two care programs, the CAT and cognitive therapy based on mindfulness (Mindfulness-Based Cognitive Therapy, MBCT) compared to the usual care ("Treated as usual", TAU) in AM and to show their benefit on dimensions specific to EDs such as body dissatisfaction and the internalization of the ideal of thinness, but also on eating symptoms and the anxious and depressive dimensions.

The patients will be recruited from the active files of the four centers participating in the study. In order to avoid the disappointment bias, they will be randomized into three groups, according to a procedure adapted from the Zelen method, in two stages. After verification of the inclusion criteria, eligible patients will receive initial information detailing the follow-up methods, but not the intervention. If patients agree to participate, they will be randomized to three groups: CAT, MBCT or usual management. Patients in the CAT and MBCT groups will then be informed of the group in which they have been randomized, will sign a new consent form and the corresponding intervention will be offered to them.

Experimental group: 2 group programs, led by trained facilitators, addressing specific ED topics through written, verbal and/or behavioral exercises,

• by following a directive standardized manual aimed at inducing cognitive dissonance (CAT group)
• via a specific TCA mindfulness approach (MBCT group) Control group: usual management (TAU). Same number of sessions as the experimental group (8 weekly sessions), consisting of supportive psychotherapy, +/- adjunctive drug treatment, symptomatic.

HibernAM ancillary study:

For patients with restrictive anorexia nervosa, serum collection on inclusion. Collection of serum from blood samples taken as part of routine care for matched healthy subjects.

Addition of serum from patients with restrictive anorexia nervosa, and from matched healthy subjects, to human myotubes in culture for the exploration of protein metabolism

Inclusion Criteria:

• Anorexia nervosa as defined by the DSM-5 (anorexia nervosa of pure restrictive type F50.01 or purgative type F50.02),
• 14 < BMI < 18.5 (outpatient management possible)
• Affiliation to a social security scheme or beneficiary of such a scheme
• Signed informed consent

Exclusion Criteria:

• other group support of their TCA
• regular psychological follow-up for a main psychiatric disorder other than TCA
• mental retardation or psychiatric pathology other than TCA or severe somatic not allowing efficient participation in the therapeutic program and interviews
• presence, at the time of the study, of a chronic condition that typically affects weight (digestive disease such as celiac disease, Crohn's disease; malignant tumor pathology; endocrine pathology such as hypo/hyperthyroidism, hyper/ hypocortisolism, pituitary or hypothalamic tumor, etc.).
• refusal to participate in the study
• pregnant, lactating women
• period of exclusion from another study,
• administrative or judicial supervision
• subject cannot be contacted in case of emergency

Ancillary study: Volunteers will be excluded from the control group:

• having a significant biological abnormality
• a history of TCA or pathology likely to impact protein metabolism,
• pregnancy or breastfeeding at the time of the blood sample,
• under guardianship, deprivation of liberty, administrative or judicial supervision and exclusion from another study.

The patients will be recruited from the active files of the four centers participating in the study. In order to avoid the disappointment bias, they will be randomized into three groups, according to a procedure adapted from the Zelen method, in two stages. After verification of the inclusion criteria, eligible patients will receive initial information detailing the follow-up methods, but not the intervention. If patients agree to participate, they will be randomized to three groups: CAT, MBCT or usual management. Patients in the CAT and MBCT groups will then be informed of the group in which they have been randomized, will sign a new consent form and the corresponding intervention will be offered to them.