Caloric Intake Changes for Diet-Induced Thermogenesis in Obesity

Overseen By Tomas Cabeza De Baca, Ph.D.

Age: 18 - 65

Sex: Any

Trial Phase: Academic

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

Must not be taking: Energy metabolism drugs

Disqualifiers: Diabetes, Hypertension, Cardiovascular, others

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

Compensation: Varies

Number of Visits: 3

120 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore how different diets impact the body's energy use during digestion, known as diet-induced thermogenesis. Researchers will study how varying amounts of protein, fat, carbohydrates, and total calories affect energy use. Participants will try eight different diets, including fasting and various calorie levels, to observe their effects on metabolism. The trial suits healthy individuals who haven't intentionally lost weight in the last six months and are willing to stay at a clinic for about 35 days. As an unphased trial, this study offers participants the chance to contribute to groundbreaking research on diet and metabolism.

Will I have to stop taking my current medications?

Yes, you will need to stop taking any medications, dietary supplements, or alternative therapies that are known to alter energy metabolism.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that both increasing and decreasing calorie intake can affect the body's energy use, and both approaches are generally safe for healthy individuals. One study on high-calorie diets found that consuming more calories can increase the energy the body uses to process food, allowing it to handle extra calories by burning more energy.

Conversely, research on reduced calorie intake has shown it to be safe as well, often resulting in weight loss and changes in energy use. Fasting, another method of reducing calorie intake, has proven as effective as consistently eating less for weight loss and is generally well-tolerated.

These studies focus on dietary changes rather than new medications, which reduces the risk of side effects. Participants in similar studies did not report major side effects. However, individual experiences can vary, so monitoring the body's response is important. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores how different caloric intake levels can impact diet-induced thermogenesis in individuals with obesity. Unlike standard treatment options that often focus on calorie restriction or medication, this trial investigates various dietary modifications, including significant caloric increases and fasting, to understand their unique effects on metabolism. By studying diverse dietary compositions and energy balances, the trial aims to uncover new insights into how different nutritional strategies can optimize energy expenditure and potentially aid in weight management. This approach could lead to personalized dietary recommendations that better support metabolic health in individuals with obesity.

What evidence suggests that this trial's treatments could be effective for diet-induced thermogenesis in obesity?

Research has shown that different diets can significantly affect diet-induced thermogenesis (DIT), the energy your body uses to digest food. This trial will explore various dietary regimens, including high-calorie diets and fasting, to assess their impact on DIT in individuals with obesity. Studies have found that consuming high-calorie foods can increase DIT, helping the body burn more energy, although this effect varies among individuals. Conversely, fasting has aided in weight loss and improved overall metabolic health. Intermittent fasting, in particular, offers similar benefits to consistently eating fewer calories for weight loss. Both high-calorie diets and fasting are linked to various health outcomes, but individual responses may differ. Participants in this trial will follow different dietary regimens to evaluate these effects. ^{6 7 8 9 10}

Who Is on the Research Team?

Tomas Cabeza De Baca, Ph.D.

Principal Investigator

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

Are You a Good Fit for This Trial?

Healthy adults aged 18-60 who haven't tried to lose weight on purpose in the last 6 months can join this study. People with heart, brain, lung diseases, diabetes, endocrine or kidney disorders, liver disease, certain cancers or infections, alcohol/drug abuse issues or pregnant/lactating women cannot participate.

Inclusion Criteria

No episodes of intentional weight loss over previous 6 months

Exclusion Criteria

Current use of tobacco products that exceed 'Very Low Dependence' on the Fagerstrom Test for Nicotine Dependence Tool (score greater than 2)

I have diabetes with high blood sugar or a history of diabetes.

Evidence of alcohol abuse as defined by >=8-point score on the Alcohol consumption screening AUDIT questionnaire in adults

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1 week

1 visit (in-person)

Baseline Assessment

Initial measurements including waist, thigh, and neck circumference, DXA scan, diabetes testing, and questionnaires on eating behavior, hunger, and stress

1 week

Multiple visits (in-person)

Dietary Intervention

Participants receive 8 different diets, including 7 test diets, and undergo multiple tests including daily weight measurements, blood tests, and metabolic chamber assessments

4 weeks

Daily monitoring (in-person)

Follow-up

Participants are monitored for safety and effectiveness after the dietary intervention

2 weeks

2 visits (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• +150% of dietary requirements, 51% of the calories from carbohydrates, 46%, from fat and 3% from protein
• +150% of energy balance requirements, 50% of calories from carbohydrates, 20% from protein, and 30% from fat
• +200% of dietary requirements, 50% of calories from carbohydrates, 20% from protein, and 30% from fat
• -25% of energy balance requirements, 50% of calories from carbohydrates, 20% from protein, and 30% from fat
• -50% of energy balance requirements. 50% of calories from carbohydrates, 20% from protein, and 30% from fat
• Fasting

Trial Overview The trial is testing how different diets affect the body's energy use after eating. Participants will stay in a clinic for about 34 days and try out eight diet variations with differing amounts of calories from carbs, proteins and fats while undergoing various tests including blood work and staying in a metabolic chamber.

How Is the Trial Designed?

Group I: Set 10 Active Control 7 Interventions

+200% LPF -25% Fasting +200% SOF -50% +150% LPF +150% SOF

Group II: Set 4 Active Control 7 Interventions

Fasting -25% +200% LPF -50% +200% SOF +150% SOF +150% LPF

Group III: Set 3 Active Control 7 Interventions

+150% LPF Fasting +150% SOF -25% +200% SOF +200% LPF -50%

Group IV: Set 9 Active Control 7 Interventions

+150% SOF -25% +150% LPF +200% SOF Fasting +200% LPF -50%

Group V: Set 1 Active Control 7 Interventions

+150% LPF +150% SOF -50% +200% LPF +200% SOF Fasting -25%

Group VI: Set 2 Active Control 7 Interventions

+150% LPF +200% LPF -50% +150% SOF Fasting -25% +200% SOF

Group VII: Set 5 Active Control 7 Interventions

-25% +150% SOF +200% LPF +150% LPF Fasting +200% SOF -50%

Group VIII: Set 6 Active Control 7 Interventions

Fasting +200% LPF +200% SOF -50% +150% LPF -25% +150% SOF

Group IX: Set 7 Active Control 7 Interventions

-50% +200% SOF -25% +150% SOF Fasting +200% LPF +150% LPF

Group X: Set 8 Active Control 7 Interventions

-50% +150% SOF +200% SOF +150% LPF -25% +200% LPF Fasting

Who Is Running the Clinical Trial?

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

Lead Sponsor

Trials

2,513

Recruited

4,366,000+

Published Research Related to This Trial

In a study involving 30 women (15 lean and 15 obese), diet-induced thermogenesis (DIT) was found to be significantly higher after consuming a protein-rich meal compared to a fat-rich meal, regardless of body weight status.

However, there were no significant differences in DIT or macronutrient oxidation rates between lean and obese women after consuming either meal, suggesting that low DIT from frequent fat intake may contribute to obesity maintenance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Diet-induced thermogenesis and substrate oxidation are not different between lean and obese women after two different isocaloric meals, one rich in protein and one rich in fat. Tentolouris, N., Pavlatos, S., Kokkinos, A., et al.[2011]

Very low calorie diets can lead to significant weight loss, averaging 20 kg in just 12 weeks, making them effective for treating moderate to severe obesity.

When conducted under careful medical supervision for up to 3 months, these diets are considered safe, with no diet-related fatalities reported in over 10,000 cases, contrasting sharply with earlier liquid protein diets that had serious safety concerns.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Very low calorie diets: their efficacy, safety, and future. Wadden, TA., Stunkard, AJ., Brownell, KD.[2022]

Obese women oxidized a higher percentage of fat energy (40.2%) compared to normal weight women (36.0%) despite both groups consuming a diet with the same fat energy percentage (30%), indicating a link between fat mass and fat oxidation.

Post-obese subjects showed normal insulin sensitivity but struggled to appropriately adjust their fat to carbohydrate oxidation ratios on a high-fat diet (50% fat energy), leading to a positive fat balance and negative carbohydrate balance, suggesting potential metabolic adaptations following obesity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dietary composition, substrate balances and body fat in subjects with a predisposition to obesity. Astrup, A.[2014]

A low-energy protein diet, used for 28 days with 49 obese patients, resulted in an average weight loss of 10.6 kg and a significant reduction in BMI, indicating its efficacy for obesity treatment.

The diet improved cardiovascular risk factors, leading to lower blood pressure, cholesterol, and insulin levels, while being well tolerated with fewer side effects compared to intermittent fasting.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[A Czechoslovak low-energy protein diet in the treatment of obesity]. Hainer, V., Kunesová, M., Stich, V., et al.[2006]

A study involving 30 overweight individuals showed that consuming a higher protein diet (35% of energy) in six meals per day led to greater reductions in body fat and abdominal fat compared to traditional protein intake over three meals.

The higher frequency of meals not only decreased body fat but also increased lean body mass and postprandial thermogenesis, suggesting that eating more often with higher protein can improve metabolic health during both energy balance and deficit phases.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Increased protein intake and meal frequency reduces abdominal fat during energy balance and energy deficit. Arciero, PJ., Ormsbee, MJ., Gentile, CL., et al.[2013]

Obesity can result from both excessive food intake (hyperphagia) and a reduced ability to burn energy (thermogenic capacity), with factors like sympathetic nervous system sensitivity and insulin resistance playing a role in this energy imbalance.

A protein-sparing modified fast, which emphasizes high protein intake while reducing carbohydrates and fats, can help in weight loss, but after losing weight, individuals need to adjust their diet to maintain lower fat intake and allow for some carbohydrates, as their energy needs decrease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Physiopathology and treatment of obesity]. Jéquier, E.[2008]

A high-protein diet (1.2 g/kg body weight) during weight loss and maintenance helps sustain satiety and energy expenditure while preserving fat-free mass, which is crucial for long-term weight management.

The review indicates that adequate protein intake can improve body composition and blood pressure without causing kidney issues in healthy individuals, making it a safe and effective strategy for combating obesity and metabolic syndrome.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dietary protein - its role in satiety, energetics, weight loss and health. Westerterp-Plantenga, MS., Lemmens, SG., Westerterp, KR.[2022]

High-protein diets are the most effective at increasing thermogenesis compared to high-carbohydrate and high-lipid diets, which can help in energy expenditure and potentially aid in obesity prevention.

Protein is the most satiating macronutrient, while fat is the least, indicating that diet composition can significantly influence energy intake and feelings of fullness, which is important for managing obesity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Macronutrient profile affects diet-induced thermogenesis and energy intake]. Hermsdorff, HH., Volp, AC., Bressan, J.[2016]

Diet-induced thermogenesis, which is the increase in energy expenditure after eating, can account for 5 to 15% of daily energy expenditure, depending on the diet's macronutrient composition.

Protein and alcohol significantly enhance diet-induced thermogenesis, while high fat consumption reduces it; this suggests that protein not only helps with energy expenditure but also plays a crucial role in regulating body weight by promoting feelings of fullness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Diet induced thermogenesis. Westerterp, KR.[2022]

Citations

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