This study will compare the safety and effectiveness of a low carbohydrate diet (Atkins Diet) with a high carbohydrate diet (conventional USDA diet).

Condition	Intervention	Phase
Obesity	Behavior: Atkins Diet	Phase IV

Further Study Details: 

Expected Total Enrollment:  360

Despite the considerable mass appeal of popular diet books, such diet approaches lack data to support their efficacy and safety. Despite its widespread use for more than 30 years, the Atkins diet has never been evaluated in a large, randomized, controlled trial. This study will assess the short-term and long-term clinical effects of a low-carbohydrate diet and a high-carbohydrate diet in overweight and obsese men and women.

Participants in this study will be randomly assisgned to the Atkins diet (low-carbohydrate, unlimited fat and protein) or a conventional USDA diet(high-carbohydrate, low fat). The study will evaluate the effects of each dietary approach on changes in: 1) weight and body composition, 2) metabolic and organ function, 3) exercise tolerance. Each participant will be enrolled in the study for 2 years.

Ages Eligible for Study:  18 Years   -   65 Years,  Genders Eligible for Study:  Both

Accepts Healthy Volunteers

Criteria

Inclusion Criteria:

• Body mass index between 30 and 40
• Live and work within 1 hour of the study site
• Stable psychological status

Exclusion Criteria:

• History of heart disease, heart attack, or stroke
• Blood pressure > 140/90 mmHG
• Abnormal cholesterol levels
• Significant psychiatric illness
• Any medication that affects weight or metabolic rate
• Presence or history of a chronic disease that is known to affect appettite, food intake, or metabolism (i.e. diabetes, thyroid disease or cancer).
• Currently using antidepressants, steroids, tobacco or illegal drugs
• Pregnant, breastfeeding, or planning pregnancy
• 10 lb change in weight within 6 months of study entry
• History of malignant arrhythmias or cerebrovascular, renal, or hepatic disease
• History of protein wasting diseases or gout
• Severe arthritis
• Osteoperosis
• Certain types of hormone replacement therapy
• Currently following a vegetarian diet

Colorado
      University of Colorado, Denver,  Colorado,  United States
Missouri
      Washington University, St. Louis,  Missouri,  United States
Pennsylvania
      University of Pennsylvania, Philadelphia,  Pennsylvania,  United States

Study chairs or principal investigators

Gary Foster, PhD,  Principal Investigator,  University of Pennsylvania   
Holly Wyatt, MD,  Principal Investigator,  University of Colorado   
James Hill, PhD,  Principal Investigator,  University of Colorado   
Samuel Klein, MD,  Principal Investigator,  Washington University School of Medicine   

Study ID Numbers:  707315; 1 R01 AT01103-01
Last Updated:  September 1, 2005
Record first received:  September 1, 2005
ClinicalTrials.gov Identifier:  NCT00143936
Health Authority: United States: Institutional Review Board
ClinicalTrials.gov processed this record on 2005-09-13