Effects of Caffeine and Coffee on Resting Metabolic Rate, Comparing Normal Weight Men to Obese Men (RMR)
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT02751840 |
Recruitment Status :
Completed
First Posted : April 26, 2016
Last Update Posted : April 27, 2016
|
- Study Details
- Tabular View
- No Results Posted
- Disclaimer
- How to Read a Study Record
Background. The prevalence of obesity has increased in the last two decades. To maintain body weight energy expenditure (EE) should be equal to energy intake (EI). A low EE predisposes individuals to weight gain and to obesity that can also results from low resting metabolic rate (RMR). Caffeine (Caf) is an active food ingredient and is widely consumed globally, and has an important impact on energy balance. Caf reduces appetite (EI) and increases EE, thus, Caf has a potential role in body weight reduction. Caf causes higher total daily energy expenditure (TDEE) in normal weight (NW) people compared to obese (OW). Moreover Caf is linked to decreased fat oxidation in OW. There are differences between OW and NW in Caf pharmacokinetics, but no differences reported between NW and OW females in its effects on RMR. There is a gender difference in the influence of Caf on metabolism. The investigators are aware of no previous studies which compared the effect of Caf on the RMR of NW and OW men.
Objectives. 1) To compare the effect of Caf and coffee on resting metabolic rate (RMR) values in healthy normal-weight (NW) men and overweight (OW) men. 2) To develop Caf intake frequency questionnaire (in Hebrew)
Hypothesis. RMR values will be higher and respiratory exchange ratio (RER) values will be lower in NW compared to the values measured in OW men.
Methods. 33 men (16 NW and 17 OW) were reported to the laboratory on 4 separate occasions (placebo, Caf tablets, coffee and decaffeinated coffee). During the lab sessions they were undergo complete anthropometric measurements and RMR measured (one of the study conditions) using indirect calorimetry. Additionally, respiratory exchange ratio (RER) which is calculated as the ratio between CO2 production (VCO2) and O2 consumption (VO2) (VCO2/VO2), blood pressure and heart rate (HR) response recorded.
The importance of this study is that the results will contribute to the scientific basis of weight control and health interventions programs (diet and physical activity) in overweight men.
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Asymptomatic Conditions | Dietary Supplement: Caffeine Dietary Supplement: Placebo Other: Coffee Other: Decaffeinated | Phase 3 |
Methods. 16 NW and 17 OW men were reported to the laboratory on 4 separate occasions (placebo, Caf tablets, coffee and decaffeinated coffee) each separated by 2-7 days. Before the first meeting they refill caffeine, physical activity and medical questionnaires. The investigators recruited only men who were healthy non-smokers with no comorbidities and the daily caffeine consumption was under 400 mg. Before each meeting participants had to comply guidelines outlined included fasting for 8 hours, avoiding intense physical activity 14 hours and moderate exercise 2 hours before measurements. The meetings conducted in the morning when the first session included anthropometric measurements (weight, height and waist circumference) and body composition measurements using Bioelectrical Impedance Analysis (BIA) and a digital caliper. Each session began with a measuring resting blood pressure and heart rate (Polar telemetric systems), after that participants were given randomly placebo or Caf tablets or coffee or decaffeinated coffee, waiting half an hour and then measuring the RMR and respiratory exchange ratio (RER), for half an hour using indirect calorimetry (canopy system). Then again measured blood pressure and heart rate at rest.
The sample size was calculated for 16 participant in each group, according to an expected change of 3% at RMR values between the groups with the power of 80% and significance of 0.05 . standard deviation (SD).
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 33 participants |
Allocation: | Randomized |
Intervention Model: | Crossover Assignment |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Basic Science |
Official Title: | Effects of Caffeine and Coffee on Resting Metabolic Rate, Comparing Normal Weight Men to Obese Men |
Study Start Date : | October 2014 |
Actual Primary Completion Date : | August 2015 |
Actual Study Completion Date : | April 2016 |
Arm | Intervention/treatment |
---|---|
Experimental: Caffeine
Caffeine capsule (200 mg) is taken prior to RMR measurement
|
Dietary Supplement: Caffeine
200 mg of caffeine capsule before RMR measurement Dietary Supplement: Placebo Placebo capsule (starch) before RMR measurement Other: Coffee 9 grams of black coffee in boiling water consumed before RMR measurement Other: Decaffeinated 9 grams of decaffeinated black coffee in boiling water consumed before RMR measurement |
Placebo Comparator: Placebo
Placebo (starch) capsule is taken prior to RMR measurement
|
Dietary Supplement: Caffeine
200 mg of caffeine capsule before RMR measurement Dietary Supplement: Placebo Placebo capsule (starch) before RMR measurement Other: Coffee 9 grams of black coffee in boiling water consumed before RMR measurement Other: Decaffeinated 9 grams of decaffeinated black coffee in boiling water consumed before RMR measurement |
Experimental: Coffee
Black coffee (9 grams) is consumed prior to RMR measurement
|
Dietary Supplement: Caffeine
200 mg of caffeine capsule before RMR measurement Dietary Supplement: Placebo Placebo capsule (starch) before RMR measurement Other: Coffee 9 grams of black coffee in boiling water consumed before RMR measurement Other: Decaffeinated 9 grams of decaffeinated black coffee in boiling water consumed before RMR measurement |
Placebo Comparator: Decaffeinated
Decaffeinated Black coffee (9 grams) is consumed prior to RMR measurement
|
Dietary Supplement: Caffeine
200 mg of caffeine capsule before RMR measurement Dietary Supplement: Placebo Placebo capsule (starch) before RMR measurement |
- Measurement of resting metabolic expenditure using indirect calorimetry (open flow canopy system) [ Time Frame: Within two weeks (4 sessions, each 30 minutes) ]

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, Learn About Clinical Studies.
Ages Eligible for Study: | 20 Years to 50 Years (Adult) |
Sexes Eligible for Study: | Male |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
33 Healthy men at the age between 20-50 years. 16 normal weight men and 17 obese men.
Exclusion Criteria:
- Hypertension (above 140/90 mmHg)
- Taking medications for hypertension
- Heart, liver or kidney problems, diabetes, respiratory problems, hypo/hyper thyroidism.
- Smoking
- Men who consume caffeine above 400 mg/day
- Taking medications or dietary supplements that can affect energy expenditure
- Elite athletes (competitive sport)
- Night Eating
Responsible Party: | Tel Hai College |
ClinicalTrials.gov Identifier: | NCT02751840 |
Other Study ID Numbers: |
Tel Hai College RMR-011 |
First Posted: | April 26, 2016 Key Record Dates |
Last Update Posted: | April 27, 2016 |
Last Verified: | April 2016 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Asymptomatic Diseases Disease Attributes Pathologic Processes Caffeine Central Nervous System Stimulants Physiological Effects of Drugs Phosphodiesterase Inhibitors |
Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Purinergic P1 Receptor Antagonists Purinergic Antagonists Purinergic Agents Neurotransmitter Agents |