Intermittent Fasting for Obesity

(POWER-VET Trial)

Recruiting at 1 trial location

Overseen By Kristina Marcus, MS

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: VA Office of Research and Development

Must not be taking: Insulin, Anti-coagulants

Disqualifiers: Diabetes, Autoimmune, Psychiatric, others

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

Compensation: Varies

Number of Visits: Unknown

175 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial information does not specify if you need to stop taking your current medications. However, if you are on anti-coagulant medication, it may be relevant only for muscle biopsies.

What data supports the effectiveness of the treatment Weight Maintenance + Intermittent Fasting for obesity?

Research shows that intermittent fasting can help with weight loss and improve metabolic health in people with obesity. Studies have found that it can be as effective as traditional calorie-restricted diets for losing weight. ^{1 2 3 4 5}

Is intermittent fasting safe for humans?

Intermittent fasting, including alternate day fasting, has been studied for weight loss and shows similar safety to continuous calorie restriction in the short term. However, there is limited information on its long-term safety, and more research is needed to understand its effects on different groups of people. ^{1 3 6 7 8}

How does the treatment of weight maintenance with intermittent fasting differ from other obesity treatments?

This treatment is unique because it combines weight maintenance strategies with intermittent fasting, which involves cycling between periods of eating and fasting. Unlike traditional continuous calorie restriction diets, intermittent fasting may improve adherence and enhance weight loss and metabolic health in people with obesity. ^{1 2 9 10 11}

What is the purpose of this trial?

This trial is testing intermittent fasting as a way to help overweight and obese Veterans keep weight off after losing it. Intermittent fasting involves eating only during certain times and not eating at other times. The study will also look at how muscle enzymes that burn fat might help with long-term weight management. Intermittent fasting is a popular weight management intervention that has been widely applied to the treatment of overweight and obesity in adults.

Research Team

Alice S. Ryan, PhD

Principal Investigator

Baltimore VA Medical Center VA Maryland Health Care System, Baltimore, MD

Eligibility Criteria

This trial is for veterans aged 50-75 with a BMI of 25-40, including postmenopausal women. It's not suitable for those who've had significant weight changes recently, are on blood thinners (for muscle biopsies), have impaired kidney function, serious liver disease, uncontrolled diabetes, or active major health conditions.

Inclusion Criteria

I am between 50 and 75 years old.

Your body mass index (BMI) is between 25 and 40, which means you are overweight or obese.

Veteran

Exclusion Criteria

You have a history of alcohol or drug abuse, as reported by yourself.

I have a condition that makes it hard for me to do physical tests.

I do not have active inflammatory, autoimmune, infectious, hepatic, gastrointestinal, malignant, or psychiatric diseases.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Weight Loss and Exercise

Participants undergo a weight loss and exercise program

12 weeks

Regular visits for monitoring and support

Weight Maintenance

Participants follow a weight maintenance program with or without intermittent fasting

24 weeks

Regular visits for monitoring and support

Follow-up

Participants are monitored for safety and effectiveness after the weight maintenance phase

12 weeks

Follow-up visits to assess long-term outcomes

Treatment Details

Interventions

• Weight Maintenance
• Weight Maintenance + Intermittent Fasting

Trial Overview The study is testing traditional weight maintenance methods against the addition of intermittent fasting to see if it helps prevent weight regain after loss. The goal is to find cost-effective strategies for managing obesity in adults.

Participant Groups

Group I: Weight Maintenance + Intermittent Fasting Experimental Treatment 1 Intervention

Heart Healthy nutrition, walking, resistance band exercise and intermittent fasting (2 small meals per day) one day per week for 24 weeks.

Group II: Weight Maintenance Active Control 1 Intervention

Heart Healthy nutrition, walking, resistance band exercise

Who Is Running the Clinical Trial?

VA Office of Research and Development

Lead Sponsor

Trials

1,691

Recruited

3,759,000+

South Texas Veterans Health Care System

Collaborator

Trials

19

Recruited

6,100+

Baltimore VA Medical Center

Collaborator

Trials

33

Recruited

3,000+

Baltimore Veterans Affairs Medical Center

Collaborator

Trials

5

Recruited

470+

Findings from Research

Intermittent fasting (IF) may be an effective weight management strategy for overweight and obese adults, but its evidence base in humans is still limited, with only one published systematic review available.

Current guidelines from the National Institute for Health and Care Excellence (NICE) do not recommend very low calorie diets (VLCD) as a routine treatment for obesity, highlighting concerns about potential side effects and the sustainability of fasting approaches.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intermittent fasting interventions for the treatment of overweight and obesity in adults aged 18 years and over: a systematic review protocol. Jane, L., Atkinson, G., Jaime, V., et al.[2022]

Intermittent energy restriction, which includes methods like alternate day fasting, was found to be more effective than no treatment for weight loss in overweight and obese adults, with an average loss of 4.14 kg over the study period.

However, when compared to continuous energy restriction, intermittent energy restriction did not show a significant difference in weight loss, indicating that both approaches may be similarly effective for short-term weight management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intermittent fasting interventions for treatment of overweight and obesity in adults: a systematic review and meta-analysis. Harris, L., Hamilton, S., Azevedo, LB., et al.[2022]

Modified alternate-day fasting (ADF) led to significant weight loss (5.6 kg) and reduced body fat percentage in 16 obese adults over 8 weeks, demonstrating its efficacy as a weight management strategy.

ADF also improved cardiovascular health indicators, with notable reductions in total cholesterol, LDL cholesterol, and triglycerides, suggesting it may lower the risk of coronary artery disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Short-term modified alternate-day fasting: a novel dietary strategy for weight loss and cardioprotection in obese adults. Varady, KA., Bhutani, S., Church, EC., et al.[2023]

Intermittent energy restriction (IER) strategies, such as intermittent fasting and time-restricted feeding, show similar effectiveness in weight loss compared to continuous energy restriction (CER) in adults with obesity, based on a review of randomized trials lasting at least 8 weeks.

Out of 11 studies analyzed, 9 found no significant differences in weight or body fat loss between IER and CER, suggesting that IER can be a viable alternative for obesity treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss. Rynders, CA., Thomas, EA., Zaman, A., et al.[2021]

In an 8-week study with 59 obese participants, alternate day fasting (ADF) led to a significant weight loss of 4.2%, while only a small percentage reported mild adverse effects like constipation and dizziness.

ADF was associated with improvements in eating disorder symptoms, including a decrease in depression and binge eating, suggesting that it may have beneficial effects on body image and eating behaviors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety of alternate day fasting and effect on disordered eating behaviors. Hoddy, KK., Kroeger, CM., Trepanowski, JF., et al.[2018]

In a 10-week study with 16 obese participants, alternate day modified fasting (ADMF) led to an average weight loss of 5.6 kg, demonstrating its effectiveness as a weight loss strategy.

Participants adapted well to ADMF, with significant reductions in energy intake on fasting days and no increase in hunger, while maintaining physical activity levels, suggesting that dietary and activity adaptations contribute to the weight loss observed.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dietary and physical activity adaptations to alternate day modified fasting: implications for optimal weight loss. Klempel, MC., Bhutani, S., Fitzgibbon, M., et al.[2021]

References

1. Australia pubmed.ncbi.nlm.nih.gov

Intermittent fasting interventions for the treatment of overweight and obesity in adults aged 18 years and over: a systematic review protocol. [2022]

2. Netherlands pubmed.ncbi.nlm.nih.gov

Effectiveness of intermittent fasting for weight loss in individuals with obesity: A meta-analysis of randomized controlled trials. [2023]

3. Netherlands pubmed.ncbi.nlm.nih.gov

Does the weight loss efficacy of alternate day fasting differ according to sex and menopausal status? [2022]

4. Australia pubmed.ncbi.nlm.nih.gov

Intermittent fasting interventions for treatment of overweight and obesity in adults: a systematic review and meta-analysis. [2022]

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

Short-term modified alternate-day fasting: a novel dietary strategy for weight loss and cardioprotection in obese adults. [2023]

6. Netherlands pubmed.ncbi.nlm.nih.gov

[Intermittent fasting in science and practice; what are the effects on weight and cardiometabolic health?] [2021]

7. Switzerland pubmed.ncbi.nlm.nih.gov

Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss. [2021]

8. England pubmed.ncbi.nlm.nih.gov

Safety of alternate day fasting and effect on disordered eating behaviors. [2018]

9. Netherlands pubmed.ncbi.nlm.nih.gov

Effect of intermittent versus continuous energy restriction on weight loss, maintenance and cardiometabolic risk: A randomized 1-year trial. [2019]

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

Intermittent fasting and protein pacing are superior to caloric restriction for weight and visceral fat loss. [2023]

11. England pubmed.ncbi.nlm.nih.gov

Dietary and physical activity adaptations to alternate day modified fasting: implications for optimal weight loss. [2021]