Calorie Reduction for Obesity

(CARE Trial)

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Alabama at Birmingham

Must not be taking: Antipsychotics, MAO inhibitors, Corticosteroids, Chemotherapy

Disqualifiers: Hypertension, Cancer, HIV, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

Duration: 18 months

223 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial requires that you stop taking certain medications, including antipsychotic agents, monoamine oxidase inhibitors, systemic corticosteroids, antibiotics for HIV or TB, chemotherapeutic drugs, and prescription weight loss medications.

What data supports the effectiveness of the treatment Energy Reduction for obesity?

Research shows that reducing calorie intake can lead to weight loss of 5-10 kg over six months, which is considered clinically meaningful. This approach is often the first step recommended in obesity treatment guidelines. ^{1 2 3 4 5}

Is calorie reduction generally safe for humans?

Calorie reduction, when combined with regular exercise and behavioral changes, is generally safe and can be beneficial for health. However, very low-calorie diets alone are not effective long-term, and some weight loss supplements lack rigorous safety testing. ^{6 7 8 9 10}

How does the treatment 'Energy Reduction' for obesity differ from other treatments?

The 'Energy Reduction' treatment for obesity focuses on reducing calorie intake, which can be done through moderate or severe caloric restriction. This approach is unique because it emphasizes the amount of energy consumed rather than the specific types of nutrients, and it can lead to significant short-term weight loss, although maintaining this loss requires ongoing care and lifestyle changes. ^{1 11 12 13 14}

What is the purpose of this trial?

This research study will compare two weight loss programs that provide different recommendations for how to reduce your energy (or calorie) intake to achieve weight loss in an effort to determine if fixed calorie reduction or varied calorie reduction is more effective for weight loss.

Research Team

Gareth R Dutton, PhD

Principal Investigator

University of Alabama at Birmingham, Department of Medicine, Division of Preventive Medicine

Eligibility Criteria

This trial is for adults aged 21-75 with obesity (BMI of 30-50). It's not suitable for those with certain chronic diseases, uncontrolled high blood pressure, recent heart attacks or strokes, major psychiatric disorders, or a history of significant weight loss or bariatric surgery. Pregnant women and those planning pregnancy are excluded.

Inclusion Criteria

I am between 21 and 75 years old.

Body mass index (BMI) 30-50 kg/m2

Exclusion Criteria

I have had weight loss surgery in the past.

My blood pressure is not higher than 160/100 mm Hg.

I have not had unstable chest pain in the last 6 months.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants follow either a fixed or variable calorie reduction plan to achieve weight loss

18 months

Regular visits for monitoring and support

Follow-up

Participants are monitored for safety and effectiveness after treatment

6 months

Treatment Details

Interventions

• Energy Reduction

Trial Overview The CARE Trial aims to compare two diet programs focusing on different methods of calorie reduction to see which one is more effective at helping participants lose weight. Participants will be randomly assigned to follow either a fixed calorie reduction plan or a varied calorie reduction plan.

Participant Groups

Group I: Variable Energy (or Calorie) Reduction Experimental Treatment 1 Intervention

Participants randomly assigned to this arm will be instructed to alternate between two levels of calorie reduction. One level will be a small amount of calorie reduction, while the other will be a more significant amount of calorie reduction. At the instruction of the research team, participants will periodically alternate back and forth between these two goals until their weight loss goal is achieved.

Group II: Fixed Energy (or Calorie) Reduction Active Control 1 Intervention

Participants randomly assigned to this arm will be instructed to reduce their food intake by a moderate amount and stay at this level of moderate reduction until their weight loss goal is achieved.

Who Is Running the Clinical Trial?

University of Alabama at Birmingham

Lead Sponsor

Trials

1,677

Recruited

2,458,000+

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Collaborator

Trials

2,513

Recruited

4,366,000+

Findings from Research

In a study involving 53 overweight patients, those following a healthy eating diet lost an average of 6.0 kg over 12 weeks, which was significantly more than the 4.2 kg lost by those on an energy prescription diet.

Both dietary approaches resulted in clinically significant weight loss, but the healthy eating diet proved to be more effective, suggesting the need for further research to confirm these findings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Controlled clinical trial of two weight reducing diets in a NHS hospital dietetic outpatient clinic: a pilot study. Taylor, F., Irons, L., Finn, P., et al.[2007]

In a study involving 53 overweight patients, those following a healthy eating diet lost an average of 6.0 kg over 12 weeks, which was significantly more than the 4.2 kg lost by those on an energy prescription diet.

Both dietary approaches resulted in clinically significant weight loss, but the healthy eating diet proved to be more effective, suggesting the need for further research to confirm these findings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Controlled clinical trial of two weight reducing diets in a NHS hospital dietetic outpatient clinic - a pilot study. Taylor, FC., Irons, LJ., Finn, P., et al.[2019]

Minor weight loss of 5-10% can significantly reduce health risks associated with obesity, but very low-calorie diets alone are not effective for long-term weight management.

Bariatric surgery is a safe and effective option for morbidly obese patients, especially those with additional cardiovascular risk factors, with adjustable gastric banding being a viable alternative to other surgical methods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Overweight. III. Therapeutic strategies for weight reduction]. Pijl, H., Meinders, AE.[2006]

Weight loss supplements in the U.S. are not regulated as drugs by the FDA, which means they undergo minimal testing for safety and efficacy, leading to potential risks for consumers.

Healthcare providers need to be aware of the lack of evidence supporting the effectiveness of these supplements and advocate for better regulatory oversight to protect consumers from unproven and possibly harmful products.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dietary supplements and alternative therapies for obesity: A Perspective from The Obesity Society's Clinical Committee. Kidambi, S., Batsis, JA., Donahoo, WT., et al.[2021]

A study involving over 28,000 patients found that orlistat and sibutramine have different safety profiles, with orlistat primarily causing gastrointestinal issues like diarrhea, while sibutramine was associated with central nervous system effects and hypertension.

The findings from prescription-event monitoring (PEM) were consistent with published case reports, confirming that the adverse events linked to these medications align with their distinct mechanisms of action.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The safety profiles of orlistat and sibutramine: results of prescription-event monitoring studies in England. Perrio, MJ., Wilton, LV., Shakir, SA.[2021]

In a study of 46 very obese individuals (11 inpatients and 35 outpatients), it was found that their caloric intake was directly related to their level of obesity, with both groups consuming high-calorie density foods and engaging in occasional binge eating.

By replacing high-calorie density foods with lower-calorie options, participants could potentially reduce their caloric intake by 20%, which could significantly aid in weight loss efforts.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Food intake of very obese persons: quantitative and qualitative aspects. Strain, GW., Hershcopf, RJ., Zumoff, B.[2007]

Patients on a conventional 1200 kcal/d diet with behavior modification lose about 8.5 kg in 20 weeks and maintain two-thirds of this weight loss after one year.

Those on a medically supervised very-low-calorie diet (400 to 800 kcal/d) can lose around 20 kg in 12 to 16 weeks, but both diets show weight regain over time, which can be managed with ongoing care and participation in maintenance programs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Treatment of obesity by moderate and severe caloric restriction. Results of clinical research trials. Wadden, TA.[2019]

Low-calorie diets, particularly those with a 600-kcal deficit, can lead to significant weight loss, averaging around 10 kg, especially in individuals with higher initial body weight.

Despite the effectiveness of low-calorie diets, the best methods for implementing these diets remain uncertain, as few randomized trials exist and various adjunct therapies complicate the evaluation of different dietary approaches.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low-calorie diets and sustained weight loss. Finer, N.[2007]

References

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2. England pubmed.ncbi.nlm.nih.gov

Controlled clinical trial of two weight reducing diets in a NHS hospital dietetic outpatient clinic: a pilot study. [2007]

3. England pubmed.ncbi.nlm.nih.gov

Controlled clinical trial of two weight reducing diets in a NHS hospital dietetic outpatient clinic - a pilot study. [2019]

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Resting energy expenditure of morbidly obese patients using indirect calorimetry: a systematic review. [2018]

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[Overweight. III. Therapeutic strategies for weight reduction]. [2006]

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Dietary supplements and alternative therapies for obesity: A Perspective from The Obesity Society's Clinical Committee. [2021]

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Medical therapy for obesity--current status and future hopes. [2007]

9. United States pubmed.ncbi.nlm.nih.gov

The safety profiles of orlistat and sibutramine: results of prescription-event monitoring studies in England. [2021]

10. United States pubmed.ncbi.nlm.nih.gov

Food intake of very obese persons: quantitative and qualitative aspects. [2007]

11. United States pubmed.ncbi.nlm.nih.gov

Treatment of obesity by moderate and severe caloric restriction. Results of clinical research trials. [2019]

12. England pubmed.ncbi.nlm.nih.gov

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13. United States pubmed.ncbi.nlm.nih.gov

Reducing Calorie Intake May Not Help You Lose Body Weight. [2022]

14. United States pubmed.ncbi.nlm.nih.gov

Low-calorie diets and sustained weight loss. [2007]