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Medifast 5 & 1 Plan

This study has been completed.
Medifast, Inc.
Information provided by (Responsible Party):
David Allison, Phd, University of Alabama at Birmingham Identifier:
First received: September 28, 2010
Last updated: June 17, 2013
Last verified: June 2013
The purpose of this study is to compare the effectiveness of the Medifast 5 & 1 Plan to a food-based, reduced-energy diet plan. The study will be conducted over 52 weeks, including a 26-week weight-loss phase and a 26-week weight-maintenance phase. 120 participants will be enrolled, with 60 randomized to the Medifast 5 & 1 Plan and 60 randomized to food-based, reduced-energy diet plan. Multiple measures will be performed at baseline, 26 weeks, and 52 weeks, including anthropometry, body composition, blood pressure, blood assays, and appetite sensations.

Condition Intervention
Body Weight
Weight Loss
Nutrition Disorders
Behavioral: Food-based, Reduced Energy Diet Plan
Other: Medifast 5 & 1 Plan

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Randomized Controlled Trial of the Medifast 5 & 1 Plan

Resource links provided by NLM:

Further study details as provided by University of Alabama at Birmingham:

Primary Outcome Measures:
  • Body weight [ Time Frame: 26 and 52 weeks ]

Secondary Outcome Measures:
  • Waist circumference [ Time Frame: 26 and 52 weeks ]
  • Body composition as measured by bioelectrical impedence (BIA) [ Time Frame: 26 and 52 weeks ]
  • Body mass index [ Time Frame: 26 and 52 weeks ]
  • Low-density lipoprotein cholesterol (LDL) [ Time Frame: 26 and 52 weeks ]
  • High-density lipoprotein cholesterol (HDL) [ Time Frame: 26 and 52 weeks ]
  • Triglycerides [ Time Frame: 26 and 52 weeks ]
  • Glucose [ Time Frame: 26 and 52 weeks ]
  • Liver function tests [ Time Frame: 26 and 52 weeks ]
  • High-sensitivity C-reactive protein (hs-CRP) [ Time Frame: 26 and 52 weeks ]
  • Lipid hydroperoxides [ Time Frame: 26 and 52 weeks ]
  • Blood pressure [ Time Frame: 26 and 52 weeks ]
  • Appetite/satiety measures [ Time Frame: 26 and 52 weeks ]

Enrollment: 120
Study Start Date: October 2010
Study Completion Date: April 2013
Primary Completion Date: February 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Food-based, Reduced Energy Diet Plan Behavioral: Food-based, Reduced Energy Diet Plan
Control participants will be provided with a 1000-kcal/d meal plan based on regular foods selected and procured by participants. Food lists, sample menus, and portion size references will be provided.
Experimental: Medifast 5 & 1 Plan Other: Medifast 5 & 1 Plan
Participants randomized to the Medifast group will enroll online in the Medifast 5 & 1 Plan. This plan consists of 5 portion-controlled, nutritionally-balanced Medifast Meals plus one Lean & Green Meal each day. Medifast Meals come in individual packets that are mixed with water and microwaved or refrigerated, and are available in a wide variety of foods and flavors. There are >70 Medifast Meal choices, and Medifast Meals may be used interchangeably, so any five Medifast Meals can be chosen for the 5 & 1 Plan. The Medifast 5 & 1 Plan provides approximately 800 to 1,000 kcal/d. The Lean & Green Meal consists of a lean meat plus salad and/or vegetables selected by the participant. Intervention participants will have online access to Medifast dietitians, Medifast trainers, a Medifast message board, and a Medifast chat room, allowing them to interact with others on the Medifast 5 & 1 Plan.


Ages Eligible for Study:   19 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • BMI 35-50 kg/m2
  • Interested in weight loss
  • Computer with internet access
  • Any race or ethnicity
  • Fasting glucose <126 mg/dL at screening

Exclusion Criteria:

  • Participation in any weight-reduction program, weight-loss diet, or other special diet within the previous 3 months.
  • Weight loss or gain of >5% body weight in past 6 months for any reason except post-partum weight loss.
  • Currently taking any medication that suppresses or stimulates appetite.
  • History of prior surgical procedure for weight control or liposuction.
  • Current smoker or quit smoking less than 6 months prior.
  • Any major disease, including:

    • Active cancer or cancer requiring treatment in the past 2 years (except nonmelanoma skin cancer).
    • Active or chronic infections, including self-reported HIV positivity and active tuberculosis.
    • Active cardiovascular disease or event including hospitalization or therapeutic procedures for treatment of heart disease (e.g., coronary artery bypass, percutaneous transluminal coronary angioplasty) in the past 6 months; New York Heart Association Functional Class >2 with respect to congestive heart failure; stroke or transient ischemic attack in the past 6 months.
    • Uncontrolled hypertension: systolic blood pressure >160 mm Hg or diastolic blood pressure >95 mm Hg on treatment.
    • Gastrointestinal disease, including self-reported chronic hepatitis or cirrhosis, any episode of alcoholic hepatitis or alcoholic pancreatitis within past year, inflammatory bowel disease requiring treatment in the past year, recent or significant abdominal surgery (e.g., gastrectomy).
    • Active kidney disease.
    • Lung disease: chronic obstructive airway disease requiring use of oxygen.
    • Diagnosed diabetes (type 1 or 2), fasting hyperglycemia (blood glucose >126 mg/dL), or use of any anti-diabetic medications.
  • Uncompensated or uncontrolled psychiatric disease (such as schizophrenia and bipolar disorder) that, in opinion of the investigators, would impede conduct of the trial or completion of procedures.
  • A score on the Brief Symptom Inventory (BSI) (Derogatis & Melisaratos, 1983) that exceeds the 90th percentile.
  • History of or current eating disorders, or an Eating Attitudes Test (EAT 40) score >30.
  • Active food allergies, particularly to wheat, gluten, soy or nuts.
  • Conditions or behaviors likely to effect the conduct of the trial: unable or unwilling to give informed consent; unable to communicate with the pertinent clinic staff; another household member is a participant or staff member in the trial; unwilling to accept treatment assignment by randomization; current or anticipated participation in another intervention research project that would interfere with the intervention offered in the trial; likely to move away from participating clinics before trial completed; unable to walk 0.25 mile in 10 minutes.
  • Currently taking antidepressant, steroid, or thyroid medication, unless dosage is stable.
  • No regular source of health care.
  • Any active use of illegal or illicit drugs or history of illegal or illicit drug utilization within past year
  • Excessive alcohol intake, either acute or chronic defined as any one of the following: 1) average consumption of 3 or more alcohol containing beverages daily; 2) consumption of 7 or more alcoholic beverages within a 24-hr period in the past 12 months; or 3) other evidence available to clinic staff.
  • Willing to limit alcohol intake to zero
  • Pregnancy and childbearing: currently pregnant or less than 3 months post partum; currently nursing or within 6 weeks of having completed nursing; pregnancy anticipated during study; unwilling to report possible or confirmed pregnancies promptly during the course of the trial; unwilling to take adequate contraceptive measures if potentially fertile.
  • Any other conditions which, in opinion of the investigators, would adversely affect the conduct of the trial.
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Please refer to this study by its identifier: NCT01211301

United States, Alabama
University of Alabama at Birmingham Division of Preventive Medicine
Birmingham, Alabama, United States, 35205
Sponsors and Collaborators
University of Alabama at Birmingham
Medifast, Inc.
Principal Investigator: David B. Allison, PhD. University of Alabama at Birmingham
Principal Investigator: James M. Shikany, DrPH University of Alabama at Birmingham
  More Information

Responsible Party: David Allison, Phd, Prof/Assoc Dean, University of Alabama at Birmingham Identifier: NCT01211301     History of Changes
Other Study ID Numbers: F100625001
Study First Received: September 28, 2010
Last Updated: June 17, 2013

Keywords provided by University of Alabama at Birmingham:
weight loss
randomized controlled trial

Additional relevant MeSH terms:
Body Weight
Weight Loss
Nutrition Disorders
Signs and Symptoms
Body Weight Changes processed this record on April 28, 2017