ObesityPhase 2NCT00079573
Comparison of Popular Weight Loss Diets
A Phase 2 study testing Atkins diet (extremely low carbohydrate), Zone diet (low carbohydrate, high protein) and Ornish diet (very low fat) in people with Obesity, run by National Center for Complementary and Integrative Health (NCCIH) at 1 site in United States.
Trial summary
This study will compare the safety and effectiveness of three popular weight loss plans. These plans will be compared with the USDA Dietary Guidelines. Read more about this study
- Who is it for?
- Ages 30 to 50 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Obesity
- What is being tested?
- Atkins diet (extremely low carbohydrate), Zone diet (low carbohydrate, high protein) and Ornish diet (very low fat)
- Type of treatment
- Lifestyle or therapy programme
- How many people
- 300 participants
- Where
- 1 siteUnited States
- Study dates
- Jul 2002to Jun 2004
- Phase
- Phase 2
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 30 to 50 years
- Women only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Body mass index (BMI) between 27 and 40 kg/m2
- Weight stable for last 2 months
- Not actively on a weight loss plan
- No plans to move from the area over the next 2 years
- Willing to accept random assignment
Who cannot join
- Pregnant or breastfeeding
- Within 6 months of giving birth or planning to become pregnant in the next 2 years
- Diabetes (type 1 or 2) or history of gestational diabetes
- Renal or liver disease, active neoplasms, or recent myocardial infarction
- Hyper- or hypothyroidism
- Lipid lowering medications or medications known to affect weight/energy expenditure
Show all 9Show fewer
- Excessive alcohol intake (self-reported, > 3 drinks/day)
- Postmenopausal, including surgical menopause
- Currently under psychiatric care or severely clinically depressed (> 17 on Beck Inventory)
Trial locations and contacts
1 site in 1 country.
United States1 site
Stanford Prevention Research Center
Stanford, California, 94305
About this study
Official title: Benefits & Risks of Popular Weight Loss Diets
This study will compare the safety and effectiveness of three popular weight loss plans. These plans will be compared with the USDA Dietary Guidelines.
Read the detailed description
Obesity is the single most significant, nutrition-related health issue of the new millennium. Several "medical experts" have designed and promoted weight loss diets that dramatically differ from one another and from the USDA Dietary Guidelines. These diets have gained surprisingly widespread and persistent popularity among Americans despite the lack of evidence supporting their claims. This clinical trial will provide preliminary feasibility data for a full-scale study that will examine health outcomes (e.g., benefits, risks, success) of three popular weight loss diets. The study will investigate behavioral and physiological factors that influence adherence and retention to these diet plans.
Overweight women will be randomly assigned to one of four diets for 1 year: Atkins (extremely low carbohydrate), Zone (low carbohydrate, high protein), Ornish (very low fat), or USDA/Food Pyramid (high carbohydrate/moderate-low fat). Behavioral and physiological data will be collected. Participants attend study visits at baseline, 8 weeks, 6 months, and 1 year. At these visits, measurements will include that will include weight and blood pressure measurements and blood tests. Participants will be asked to complete ten questionnaires over the course of the study to assess behavior and appetite. Participants will also undergo a DEXA scan to assess body composition.
- Conditions
- Obesity
- Being tested
- Atkins diet (extremely low carbohydrate), Zone diet (low carbohydrate, high protein), Ornish diet (very low fat)
- Keywords
- Weight Loss, Obesity, Overweight, Premenopausal women, Diet
- Medical subject headings
- Obesity, Weight Loss, Overweight
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Atkins diet (extremely low carbohydrate)Behavioural
Zone diet (low carbohydrate, high protein)Behavioural
Ornish diet (very low fat)Behavioural
What is being measured
The primary outcome is the main question the study is designed to answer.
Weight; measured at each study visit
Percent body fat; measured at each study visit
Secondary outcomes (3)
Blood lipids (cholesterol, triglycerides); measured at each study visit
Fasting insulin and glucose; measured at each study visit
Behavioral variables; measured at each study visit
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Mar 2004 (estimated)
- Study startJul 2002
- Study completionJun 2004
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for ObesityStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Enrolment
- 300 participants
Sponsor and investigators
- Lead sponsor
- National Center for Complementary and Integrative Health (NCCIH)
- Sponsor type
- US National Institutes of Health
- Collaborators
- Community Foundation of Southeastern Michigan
- Investigators
- Christopher D. Gardner, PhD, Principal investigator, Stanford University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00079573
- Sponsor's protocol ID
- R21AT001098-01A1
- Status last verified
- Aug 2006
- First submitted
- 9 Mar 2004
- Last updated
- 18 Aug 2006
- Results posted
- No
Publications
Gardner CD, Kiazand A, Alhassan S, Kim S, Stafford RS, Balise RR, Kraemer HC, King AC. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA. 2007 Mar 7;297(9):969-77. doi: 10.1001/jama.297.9.969.
PubMed 17341711
Study at a glance
From the registry record, last updated by the sponsor on 18 Aug 2006. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Benefits & Risks of Popular Weight Loss Diets
- ClinicalTrials.gov ID
- NCT00079573
- Acronym / sponsor ID
- R21AT001098-01A1
- Conditions
- Obesity
- Keywords
- Weight Loss, Obesity, Overweight, Premenopausal women, Diet
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 300 participants
- Lead sponsor
- National Center for Complementary and Integrative Health (NCCIH)US National Institutes of Health
- Collaborators
- Community Foundation of Southeastern Michigan
- Study start
- Jul 2002
- Study completion
- Jun 2004
- First posted
- 10 Mar 2004 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will compare the safety and effectiveness of three popular weight loss plans. These plans will be compared with the USDA Dietary Guidelines.
Detailed description
Obesity is the single most significant, nutrition-related health issue of the new millennium. Several "medical experts" have designed and promoted weight loss diets that dramatically differ from one another and from the USDA Dietary Guidelines. These diets have gained surprisingly widespread and persistent popularity among Americans despite the lack of evidence supporting their claims. This clinical trial will provide preliminary feasibility data for a full-scale study that will examine health outcomes (e.g., benefits, risks, success) of three popular weight loss diets. The study will investigate behavioral and physiological factors that influence adherence and retention to these diet plans.
Overweight women will be randomly assigned to one of four diets for 1 year: Atkins (extremely low carbohydrate), Zone (low carbohydrate, high protein), Ornish (very low fat), or USDA/Food Pyramid (high carbohydrate/moderate-low fat). Behavioral and physiological data will be collected. Participants attend study visits at baseline, 8 weeks, 6 months, and 1 year. At these visits, measurements will include that will include weight and blood pressure measurements and blood tests. Participants will be asked to complete ten questionnaires over the course of the study to assess behavior and appetite. Participants will also undergo a DEXA scan to assess body composition.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
Who may qualify
- Ages
- 30 to 50 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Body mass index (BMI) between 27 and 40 kg/m2
- Weight stable for last 2 months
- Not actively on a weight loss plan
- No plans to move from the area over the next 2 years
- Willing to accept random assignment
Key exclusion criteria (9 listed)
- Pregnant or breastfeeding
- Within 6 months of giving birth or planning to become pregnant in the next 2 years
- Diabetes (type 1 or 2) or history of gestational diabetes
- Renal or liver disease, active neoplasms, or recent myocardial infarction
- Hyper- or hypothyroidism
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Atkins diet (extremely low carbohydrate) | Behavioural | – |
| Zone diet (low carbohydrate, high protein) | Behavioural | – |
| Ornish diet (very low fat) | Behavioural | – |
Primary outcome
Weight; measured at each study visit
Percent body fat; measured at each study visit
3 secondary outcomes
Blood lipids (cholesterol, triglycerides); measured at each study visit
Fasting insulin and glucose; measured at each study visit
Behavioral variables; measured at each study visit
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Aug 2006.
- Derived from this study: PubMed 17341711Gardner CD, Kiazand A, Alhassan S, Kim S, Stafford RS, Balise RR, Kraemer HC, King AC. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA. 2007 Mar 7;297(9):969-77. doi: 10.1001/jama.297.9.969.
- Stanford Center for Research in Disease PreventionLink provided by the sponsor.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Christopher D. Gardner, PhD principal investigator
Stanford University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Atkins diet (extremely low carbohydrate), Zone diet (low carbohydrate, high protein) and Ornish diet (very low fat) in people with Obesity, run by National Center for Complementary and Integrative Health (NCCIH) at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 18 Aug 2006. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Weight; measured at each study visit. The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT00079573, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Aug 2006.