Feasibility and Preliminary Efficacy of a Reverse Diet as a Novel Weight Loss Maintenance Strategy for Weight-Reduced Adults With Overweight/Obesity

The purpose of this project is to test, for the first time, a reverse diet in adults with current or prior overweight/obesity (Ow/Ob). Weight-reduced adults with current or prior Ow/Ob will be randomized to a reverse diet or "standard care" control (CON) intervention for 12 weeks. Eligible participants will have lost \>10% body mass. The reverse diet group will receive personalized caloric intake goals, increasing 2-3%/week. The CON group will receive standard weight maintenance recommendations with matched contact. At baseline and week 12, resting energy expenditure (REE), body mass and composition, subjective appetite, and food intake behaviors will be evaluated. In addition to the pre- and post-intervention measures, body mass and adherence to reverse diet will be monitored weekly.


Eligibility Criteria:
Inclusion Criteria:

* All ethnic groups and both genders
* Age: 21-70 years
* BMI: 18.5-40 kg/m2
* Weight loss of \>10% body mass achieved within 4 weeks of enrollment in study.

Exclusion Criteria:

* Uncontrolled cardio metabolic disease such as: cardiovascular disease (CVD), diabetes mellitus, hypertension (defined as: systolic blood pressure \>160 mmHg or diastolic blood pressure \>100mmHg, as measured during the screening visit with participants seated quietly, following established guidelines), renal disease (e.g. chronic kidney disease, polycystic kidney disease, nephritis, etc.), hepatic disease (e.g. cirrhosis, liver failure, fatty liver, jaundice, etc.), untreated thyroid disease (e.g. Grave's disease, Hashimoto's disorder, goiters, thyroid cancers, etc.), or any other medical condition affecting weight or energy metabolism. Participants who are deemed ineligible based upon uncontrolled hypertension criteria will be referred to their primary care physicians for treatment. If these conditions become controlled they will be allowed to be re-evaluated for inclusion in the current trial.
* Symptoms suggestive of CVD: chest pain, shortness of breath at rest or with mild exertion, syncope.
* Significant gastrointestinal disorders including: inflammatory bowel disease requiring treatment within the past year, chronic malabsorptive conditions, chronic diarrhea, or active gallbladder disease.
* Use of pharmacotherapy agents to achieve weight loss prior to study enrollment.
* Current treatment with medications known to significantly affect appetite, weight, energy metabolism, energy intake or energy expenditure. (e.g. systemic corticosteroids, appetite suppressants, lithium, stimulants, anti-psychotics, tricyclic antidepressants).
* History of surgical or endoscopic procedure for weight loss at any time (e.g. gastroplasty, gastric bypass, gastrectomy or partial gastrectomy, adjustable banding, gastric sleeve, intragastric balloons, aspiration therapy, etc); history of extensive bowel resection for other reasons.
* Currently pregnant, lactating or less than 6 months post-partum.
* Planning to become pregnant during study enrollment period
* Self-report of alcohol or substance abuse within the past 12 months.
* History of clinically diagnosed eating disorders including anorexia nervosa, bulimia, binge eating disorder, or score \>20 on the EATS-26. Participants with a score \>20 on the EATS-26 will be referred to their primary care physician for further evaluation.
* Major psychiatric disorder (e.g. diagnosis of schizophrenia, bipolar disorder, or other psychotic disorders).
* Current severe depression or history of severe depression within the previous year (based on reported history, study physician examination findings, and/or a score \>21 on the CES-D). Participants meeting any of these criteria will be referred to their primary care physician and/or the emergency department (based upon study physician determined level of severity).
* Currently participating in or planning to participate in any formal weight loss programs or clinical trials.
* Other medical, psychiatric, or behavioral limitations that may interfere with participation (as determined by study physician).
* Unable or unwilling to undergo study procedures