Effectiveness of a Low Carbohydrate Diet Versus a High Carbohydrate Diet in Promoting Weight Loss and Improved Health

This study has been completed.
Sponsor:
Collaborator:
Information provided by (Responsible Party):
Kaiser Permanente
ClinicalTrials.gov Identifier:
NCT00200720
First received: September 12, 2005
Last updated: December 4, 2012
Last verified: February 2008
  Purpose

This study will examine the effects of a low carbohydrate diet versus a high carbohydrate diet on weight loss.


Condition Intervention Phase
Obesity
Hypertension
Behavioral: Atkins diet (low carbohydrate diet)
Behavioral: DASH diet (high carbohydrate diet)
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Metabolic Consequences of High and Low Carbohydrate Diets

Resource links provided by NLM:


Further study details as provided by Kaiser Permanente:

Primary Outcome Measures:
  • Weight loss [ Time Frame: monthly ] [ Designated as safety issue: Yes ]
    Excess weight loss (greater than 5 pounds a week)would trigger patient assessment.


Secondary Outcome Measures:
  • Risk of cardiovascular disease [ Time Frame: Every six months ] [ Designated as safety issue: Yes ]
    Elevated lipids or rising blood pressure during six month safety assessments would trigger additional participant evaluation

  • bone health [ Time Frame: end of study ] [ Designated as safety issue: No ]
  • kidney function [ Time Frame: every six months ] [ Designated as safety issue: No ]
  • neuroendocrine mechanisms of hunger and satiety [ Time Frame: end of study ] [ Designated as safety issue: No ]

Enrollment: 260
Study Start Date: April 2005
Study Completion Date: June 2010
Primary Completion Date: March 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Atkins Diet
Participants randomized to this arm will consume a low carbohydrate diet as described by Dr. Robert Atkins in his book: Dr. Atkins' New Diet Revolution New York: Avon Books, 2002.
Behavioral: Atkins diet (low carbohydrate diet)
Active Comparator: DASH Diet
Participants randomized to this arm will consume the Dietary Approaches to Stop Hypertension (DASH) diet as described here: http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/new_dash.pdf
Behavioral: DASH diet (high carbohydrate diet)

Detailed Description:

The number of overweight and obese Americans has increased significantly in recent years. There are now many different diet plans being promoted by doctors and the media. The Atkins diet, a low carbohydrate nutritional plan, is especially popular; its advocates claim that following the diet will result in long-term weight loss with no negative effects. Another diet, called the Dietary Approaches to Stop Hypertension (DASH) diet, is a high carbohydrate diet designed to help treat and prevent high blood pressure. However, more thorough investigation of these claims is needed. This study will compare the short- and long-term effects of the Atkins diet to the (DASH) diet. This trial will enroll overweight and obese participants.

This study will last 30 months and will comprise two phases. Participants will be randomly assigned to either the Atkins or DASH diet for 30 months. During Phase 1, all participants will undergo 6 months of weekly group therapy to encourage weight loss. Phase 2 is a weight loss maintenance phase. During Phase 2, participants will have monthly meetings with a therapist for weight loss support. Study visits will occur at study entry and at Months 3 and 30. At each study visit, weight measurements, blood and urine collection, and x-rays will occur to determine participants' weight loss, cardiovascular health, kidney function, and bone density.

  Eligibility

Ages Eligible for Study:   21 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Body mass index (BMI) of 27 to 50
  • Fasting glucose less than 126 mg/dl
  • Total fasting cholesterol less than 260 mg/dl
  • Total fasting triglycerides less than 400 mg/dl
  • Permission of primary care provider to participate in the study
  • Normal liver and kidney function
  • Willing to modify diet and other health behaviors
  • Willing to use an acceptable method of contraception for the duration of the study

Exclusion Criteria:

  • Any medical condition that may make weight loss medically inadvisable
  • Weigh more than 400 lbs
  • History of kidney failure
  • Current use of more than 3 blood pressure medications
  • Change in blood pressure medications within 3 months prior to study entry
  • Diagnosis of cardiovascular disease within 6 months prior to study entry
  • Cancer diagnosis within 2 years of study entry. Participants with basal cell skin cancer are not excluded.
  • History of psychiatric hospitalization within 2 years prior to study entry
  • Consumption of more than three alcoholic drinks a day
  • Type I or II diabetes
  • Current use of hypolipidemics, antipsychotics, hypoglycemics, glucocorticoids, or thyroid medication
  • Plan to move during study
  • Current participation in another clinical trial
  • Pregnancy or breastfeeding
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00200720

Locations
United States, Oregon
Kaiser Permanente Center for Health Research
Portland, Oregon, United States, 97227
Sponsors and Collaborators
Kaiser Permanente
Investigators
Principal Investigator: Njeri Karanja, PhD Kaiser Permanente Northwest, Center for Health Research
  More Information

No publications provided

Responsible Party: Kaiser Permanente
ClinicalTrials.gov Identifier: NCT00200720     History of Changes
Other Study ID Numbers: R21 AT000525-01, R21AT000525-01, 1R01AT001930
Study First Received: September 12, 2005
Last Updated: December 4, 2012
Health Authority: United States: Federal Government

Keywords provided by Kaiser Permanente:
Diet
Carbohydrates
Weight Loss

Additional relevant MeSH terms:
Hypertension
Obesity
Vascular Diseases
Cardiovascular Diseases
Overnutrition
Nutrition Disorders
Overweight
Body Weight
Signs and Symptoms

ClinicalTrials.gov processed this record on July 24, 2014