The study will pilot a randomized control trial to investigate the feasibility and preliminary efficacy of two distinct parent treatments on a dietary intervention for overweight and obese adolescents.

Investigators will recruit overweight or obese adolescents (BMI >85th percentile) and parent(s) (BMI >25 kg/m2). Families will participate in one of two 4-month treatments: 1) TEENS+Parents as Coaches (PAC), engaging parents as helpers in their child's weight management, or 2) TEENS+Parent Weight Loss (PWL), engaging parents in their own weight management. All adolescents will participate in TEENS+, which includes behavioral support, nutrition education, and supervised physical activity.

For the adolescents, intervention will consist of weekly 1 hour exercise sessions and alternating weekly 1 hour behavioral and nutrition group sessions. Parents will also attend the nutrition sessions and participate in a behavioral parent-only biweekly group. Parent behavioral group sessions will be specific to the treatment arm (e.g. PAC or PWL). Assessments will consist of anthropometric measures, psychological surveys, and nutritional evaluations. Assessments will be completed at baseline, post-test and 3-month follow-up.

Inclusion Criteria:

Adolescent Inclusion Criteria:

• BMI ≥85% percentile for age and gender according to the CDC Growth Charts
• Age 12 to 16
• must reside with the primary participating parent
• parent must have a BMI ≥25 kg/m 2
• parent must be willing to participate in the protocol

Parent Inclusion Criteria:

• 18-60 years of age
• BMI ≥25 kg/m2
• must reside with the adolescent

Exclusion Criteria:

Adolescent Exclusion Criteria

• non-English speaking
• medical condition(s) that may be associated with unintentional weight change
• use of oral glucocorticoids, atypical antipsychotics, weight loss medications, or an investigational medication within 3 months of study participation;
• medical condition(s) that may be negatively impacted by exercise
• psychiatric, cognitive, physical or developmental conditions that would impair the ability to complete assessments, participate in a group, or conduct physical activity
• reports of compensatory behaviors in the past 3 months
• current pregnancy or plan to become pregnant during study period
• previous participation in HM11113, HM13833, HM20003076, IRB3008, IRB6255, HM11390, HM13468, HM14973 or HM14139
• current participation in another weight loss program; or 11) personal history of weight loss surgery.
• clinically significant depression
• clinically significant eating disorder
• change in dose of metformin, oral contraceptives, tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), or stimulant medications within 3 months prior to study participation.
• weight in excess of 400 pounds
• admission to a psychiatric hospital within the past year

Parent Exclusion Criteria

• non-English speaking
• medical condition(s) that may be associated with unintentional weight change
• use of oral glucocorticoids, atypical antipsychotics, weight loss medications, or investigational medications within 3 months of study participation
• psychiatric, cognitive, physical or developmental conditions that would impair the parent's ability to respond to assessments, participate in physical activity or participate in a group
• reports of compensatory behaviors in the past 3 months
• current pregnancy, lactation, less than 6 months post-partum, or plan to become pregnant during the study period
• past participation in IRB3354, HM11113, HM13833, HM20003076, IRB3008, IRB6255, HM11390, HM13468, HM14973 or HM14139
• currently engaged in another weight loss program, or 9) personal history of weight loss surgery.
• Severe depression or endorsing suicidal thoughts
• admission to a psychiatric hospital within the past year.

Assessors blind to hypotheses and allocation Interventionsts blinded to hypotheses