Clinical Study to Test the Effects of a Low-Carbohydrate Diet on Body Weight

The purpose of this study is to test the effects of a modified carbohydrate diet versus a portion controlled diet in overweight or obese men and women on body weight.


Eligibility Criteria:
Inclusion Criteria:

* Men and women 18 to 65 years of age.
* Waist circumference measurement at Visit 1 (week -1) of ³ 87 cm for females and ³ 90 cm for males.
* Subject agrees to discontinue all use of supplements or multivitamins (except for those provided during study period) by Visit 2 (week 0).
* Normally active and judged to be in good health on the basis of medical history and routine laboratory tests.
* Subject must be willing to follow the assigned diet and maintain usual physical activity level throughout the trial.
* Subject understands the procedures and requirements of the study by providing written informed consent and authorization for protected health information disclosure.

Exclusion Criteria:

* Weight loss of \> 10 lb in the two months prior to screening.
* Body mass index (BMI) \> 37.0 kg/m2.
* Current smoker (any cigarette use) or history of smoking within 6 months prior to screening.
* Postmenopausal women who are current users of hormone therapy or have discontinued hormone therapy within 2 months prior to screening.
* History or presence of significant cardiac, renal, hepatic, pulmonary, biliary, or endocrine disorders.
* Uncontrolled hypertension (systolic blood pressure ³ 160 mm Hg or diastolic blood pressure ³ 100 mm Hg on two consecutive visits).
* History of recurrent nephrolithiasis, or an acute episode of nephrolithiasis within the last year prior to screening.
* History of symptomatic cholelithiasis, unless subject has undergone cholecystectomy.
* History of gastrointestinal surgery for weight-reducing purposes.
* Active gastrointestinal disorders such as peptic ulcer disease or malabsorption syndromes (controlled lactose intolerance or gastroesophageal reflux disease are acceptable.)
* Pancreatic disease: pancreatic enzyme deficiency, history of pancreatitis.
* Fasting blood glucose ≥ 126 mg/dL at visit 1 or diagnosed diabetes mellitus.
* Use of any weight loss medications, supplements, programs, or meal replacement products intended to alter body weight within 4 weeks of the screening visit or during the course of the study. Occasional use of meal replacement bars or shakes as snacks is acceptable.
* History or presence of cancer in the past 2 years, except for successfully resected basal cell carcinoma of the skin.
* Psychiatric disorders requiring medications (i.e., selective serotonin reuptake inhibitors) or which could interfere with the subject's compliance to the requirements of the protocol.
* History or current presence of any diagnosed eating disorders (binge eating, bulimia, history of anorexia).
* Use of systemic corticosteroids, androgens, or phenytoin.
* Use of pseudo-ephedrine during the study period.
* Use of lipid-lowering drugs or supplements, unless dose stable prior to enrollment (2 months prior for drugs, 2 weeks prior for supplements).
* Use of drugs for regulating hemostasis, other than stable dose aspirin.
* Use of thyroid hormones, except stable-dose replacement therapy for ≥ 2 months prior to enrollment.
* Abnormal laboratory test results of clinical significance, including, but not limited to total cholesterol \> 300 mg/dL or triglycerides \> 400 mg/dL.
* Females who are pregnant, planning to be pregnant during the study period, lactating, or women of childbearing potential who are not using an approved method of contraception. A woman is considered to be of childbearing potential unless she is post-hysterectomy, post-tubal ligation, or ³ 1 year postmenopausal.
* Recent history of (within past 12 months) or strong potential for alcohol or substance abuse. Alcohol abuse will be defined as \> 14 drinks per week (1 drink = 12 oz beer, 4 oz wine, or 1 ½ oz distilled spirits).
* Participation in another clinical study within 30 days prior to screening visit (week -1).
* Individual has a condition the Investigator believes would interfere with the evaluation of the subject or put the subject at undue risk.