AzTrials
AzTrials

ObesityNCT02944253

What is the Maximum Amount of Carbohydrates That is Still Able to Induce Ketosis and Suppress Appetite?

A study testing Low energy diet 70 gram carbohydrates, Low energy diet 100 gram carbohydrates and Low energy diet 130 gram carbohydrates in people with Obesity, run by Norwegian University of Science and Technology at 1 site in Norway.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

Two dietary approaches, very low energy diets (VLEDs) and ketogenic low carbohydrate diets (KLCDs), have the ability to suppress appetite. The suppression of appetite typically observed during these diets is believed (but not clinically proven) to be due to ketosis, a condition where circulating concentrations of… Read more about this study

Who is it for?
Ages 18 to 65 yearsHealthy volunteers can take part
Conditions the study is for
Obesity
What is being tested?
Low energy diet 70 gram carbohydrates, Low energy diet 100 gram carbohydrates and Low energy diet 130 gram carbohydrates
Could I receive a placebo?
No, everyone receives an active treatment
How many people
100 participants
Where
1 siteNorway
Study dates
1 May 2017to 31 Dec 2019
Phase
Interventional
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 18 to 65 years
  • All sexes
  • Healthy volunteers accepted
  • Adult, Older adult

Who may be able to join

  • class I or II obesity (BMI 30-45 kg/m2)
  • weight stable (<2 kg variation in weight within the last 3 months)
  • not currently dieting to lose weight
  • women who are either post-menopausal, taking oral contraceptives or with a normal cycle (28 ± 2 days)

Who cannot join

  • pregnant
  • breast-feeding
  • drug or alcohol abuse within the last two years
  • currently taking medication known to affect appetite or induce weight loss
  • enrolled in another obesity treatment program
  • history of psychological disorders
Show all 12Show fewer
  • having had bariatric surgery
  • metabolic diseases (such as hypo/hyperthyroidism and diabetes type 1 or 2)
  • eating disorders
  • lactose intolerance
  • gastrointestinal (particularly cholelithiasis), kidney, liver, lung, cardiovascular disease
  • malignancies

Trial locations and contacts

1 site in 1 country.

Norway1 site
  • St Olavs Hospital

    Trondheim

Other trials in Norway

About this study

Official title: Ketosis and Appetite Suppression - What is the Maximum Carbohydrate Intake That is Still Associated With Appetite Suppression in a Low Energy Diet?

Two dietary approaches, very low energy diets (VLEDs) and ketogenic low carbohydrate diets (KLCDs), have the ability to suppress appetite. The suppression of appetite typically observed during these diets is believed (but not clinically proven) to be due to ketosis, a condition where circulating concentrations of ketone bodies are increased due to a higher production of ketones in the liver. Little is known about the potential mechanisms through which ketosis may lead to appetite suppression in VLEDs and KLCDs. A 'ketogenic diet' typically contains less than 50 grams carbohydrate per day, yet ketosis has been seen in subjects who consume diets with a carbohydrates ranging between 59-192 grams per day. Although an association between ketosis and appetite suppression has been established, the minimum level of ketosis and maximum carbohydrate intake that is still associated with appetite suppression remains unknown and should be explored. The ability to increase carbohydrate intake while maintaining a suppressed appetite will allow dieters to consume more carbohydrate-rich food that is beneficial for health without feeling more hungry.

The study, 'can Appetite Suppression be achieved using KEtogenic Diets with more carbohydrates?' (ASKED) aimed to:

  • to identify the maximum carbohydrate intake that is still associated with appetite suppression in a low energy diet and to determine the impact of a higher carbohydrate intake on appetite suppression, ketosis, body composition, and resting metabolic rate. A
  • to evaluate the impact of weight loss while in and out of ketosis on markers of appetite (appetite related hormones and appetite sensations measured using visual analogue scales).
Read the detailed description

A total of 101 healthy, weight stable (< 2 kg variation in BW within the last 3 months), adult (18-65 years old) individuals with obesity (body mass index [BMI] 30-45 kg/m2) who were not actively trying to lose weight were recruited through advertisements in Facebook, Twitter and the intranet of St. Olavs Hospital and the Norwegian University of Science and Technology (NTNU) in Trondheim, Norway from May 2017 - August 2018.

Informed consent was obtained from all participants before enrollment in the study, and participants were allowed to withdraw at any time.

Study participants were randomized to one of three intervention arms: low, medium, or high CHO groups. Computer-generated randomization was performed using a block sampling (fixed block size) and stratification approach to account for the potential confounding factors of sex and BMI (< 35 and ≥ 35 kg/m2). (34, 35). Study participants were not made aware of which intervention arm they were allocated to until the end of the trial. All participants underwent an 8-week, supervised LED containing different amounts of CHO, followed by 4 weeks of gradual refeeding and weight stabilization. Measurements were taken before diet initiation (baseline), at the end of the WL phase (week 8) and at the end of the weight stabilization phase (week 12) to allow for the evaluation of the impact of WL in or out of ketosis on appetite markers.

Conditions
Obesity
Being tested
Low energy diet 70 gram carbohydrates, Low energy diet 100 gram carbohydrates, Low energy diet 130 gram carbohydrates
Keywords
Diet, Reducing, Hunger, Appetite Regulation, Ketogenic Diet, Caloric Restriction, Weight Loss, Ketosis
Medical subject headings
Obesity, Weight Loss, Ketosis

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Low energy diet 70 gram carbohydratesOther

    isocaloric 4128 kilojoules/day (1000 kilocalories/day) for men and women, low energy diet containing 70 gram carbohydrates

  • Low energy diet 100 gram carbohydratesOther

    isocaloric 4128 kilojoules/day (1000 kilocalories/day) for men and women

  • Low energy diet 130 gram carbohydratesOther

    isocaloric 4128 kilojoules/day (1000 kilocalories/day) for men and women, low energy diet containing 130 gram carbohydrates

Study groups in NCT02944253
Study groupRoleWhat they receive
Low energy diet 70 gram carbohydratesExperimentalisocaloric 4128 kilojoules/day (1000 kilocalories/day) for men and women, low energy diet containing 70 gram carbohydrates for 8 weeks.
Receives: Other: Low energy diet 70 gram carbohydrates
Low energy diet 100 gram carbohydratesExperimentalisocaloric (4128 kilojoules/day (1000 kilocalories/day) for men and women, low energy diet containing 100 gram carbohydrates for 8 weeks.
Receives: Other: Low energy diet 100 gram carbohydrates
Low energy diet 130 gram carbohydratesExperimentalisocaloric 4128 kilojoules/day (1000 kilocalories/day) for men and women, low energy diet containing 130 gram carbohydrates for 8 weeks.
Receives: Other: Low energy diet 130 gram carbohydrates

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Suppression of appetite sensations measured using online visual analogue scales

    Assessed by an online version of Visual Analogue Scale (VAS), a validated scale used to measure appetite sensations in response to questions posed regarding feelings of hunger, fullness, desire to eat, prospective consumption. Study participants are asked questions such as 'How hungry do you feel right now?' and are asked to provide a response by marking across a 100 millimeter long line with sentences anchored at each end such as "I have never been more hungry/ or I am not hungry at all" corresponding to their feeling. VAS measurements are done in fasting, immediately after a meal and every 30 minutes for 2.5 hours. Measurements are quantified by measuring the distance from the left end of the line to the mark indicated by the participant.

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  2. Suppression of appetite indicated by appetite-related hormones Active Ghrelin, Total Glucagon Like Peptide-1, Total Peptide YY and Insulin

    Measurement of plasma samples of appetite related hormones: Active ghrelin (AG), Total Glucagon Like Peptide-1 (Total GLP-1), Total Peptide YY (Total PYY) and Insulin measured in fasting, immediately after a meal and every 30 minutes for a period of 2.5 hours. Blood samples are first collected in Ethylenediaminetetraacetic acid (EDTA) tubes (72 milliliters in total) and centrifuged for 10 minutes at 18 degrees celsius with 3200 revolutions per minute (RPM). Plasma samples are then stored in -80 degree celsius freezer until analysis using a Metabolic Hormone Magnetic Bead Panel (Lincoplex Kit, Merck Millipore, USA). Results of plasma samples of these hormones will be presented in picograms (pg) per milliliter (ml).

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  3. Suppression of appetite indicated by appetite-related hormone Cholecystokinin (CCK)

    Measurement of plasma samples of appetite related hormone Cholecystokinin (CCK) measured in fasting, immediately after a meal and every 30 minutes for a period of 2.5 hours. Blood samples are first collected in Ethylenediaminetetraacetic acid (EDTA) tubes (72 milliliters in total inclusive of blood collected for analysis of hormones listed above) and centrifuged for 10 minutes at 18 degrees celsius with 3200 revolutions per minute (RPM). Plasma samples are then stored in -80 degree celsius freezer until they are sent to the University of Copenhagen to be analyzed by the research group of Professor Jens F Rehfeld using his 'In-house Radioimmunoassay method'. The results of plasma CCK will be presented in picomoles (pmol) per liter (l).

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  4. Ketosis

    Measured with beta hydroxybutyrate (BHB), a ketone body and indicator of ketosis in plasma form. Fasting blood samples are first collected in Ethylenediaminetetraacetic acid (EDTA) tubes (inclusive of the 72 milliliters of blood collected for analysis of appetite hormones listed above) and centrifuged for 10 minutes at 18 degrees celsius with 3200 revolutions per minute (RPM). Plasma samples are then stored in -80 degree celsius freezer until analysis using a Ketone Body Assay (MAK-134, Merck Millipore, USA). The results of plasma BHB will be presented in millimoles (mmol) per liter (l).

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period

Secondary outcomes (9)
  1. Body composition (air displacement plethysmography)

    Body composition measured with air displacement plethysmography (BodPod, COSMED, Italy). The output of the measurement of body composition using air displacement plethysmography provides absolute values in kilograms for body weight, fat mass and fat free mass.

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  2. Percent fat/fat-free mass (air displacement plethysmography)

    Percent fat mass and fat free mass is measured with air displacement plethysmography (BodPod, COSMED, Italy). The output of the measurement of body composition using air displacement plethysmography provides fat mass and fat free mass as a percentage of total body weight.

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  3. Body composition (bioelectrical impedance)

    Body composition measured using bioelectrical impedance analysis (BIA, Biospace, Korea). The output of the measurement of body composition using bioelectrical impedance analysis provides absolute values in kilograms for body weight, fat mass and fat free mass.

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  4. Percent fat/fat-free mass (bioelectrical impedance analysis)

    Percent fat mass and fat free mass is measured with bioelectrical impedance analysis (BIA, Biospace, Korea). The output of the measurement of body composition using bioelectrical impedance analysis provides fat mass and fat free mass as a percentage of total body weight.

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  5. Intracellular and extracellular water measured using Bioelectrical impedance analysis

    Intracellular and extracellular water is measured with bioelectrical impedance analysis (BIA, Biospace, Korea). The output of the measurement of body composition using bioelectrical impedance analysis provides information on the amount total body water (made up of intracellular and extracellular water) in liters.

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  6. Waist and hip circumference

    Waist and hip circumference will be measured with a measuring tape and the results will be provided in centimeters.

    Measured: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  7. Height

    Height of the participant will be measured with a stadiometer and will be provided in meters.

    Measured: 12 weeks (at start of study (Baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  8. Body mass index (BMI)

    Body mass index (BMI) will be calculated using the measurements of body weight (obtained using the weight in kilograms output provided by bioelectrical impedance analysis) and height in meters measured using the stadiometer using the following formula: (kilograms/meters)^2

    Measured: 12 weeks (at start of study (Baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

  9. Resting metabolic rate

    Measured through indirect calorimetry. Indirect calorimetry is a technique that measures oxygen consumption and carbon dioxide production during rest to estimate resting metabolic rate. Results will be presented in kilocalories per day.

    Measured: 12 weeks (at start of study (Baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted25 Oct 2016 (estimated)
  2. Study start1 May 2017
  3. Primary completion31 Dec 2019
  4. Study completion31 Dec 2019

Resources

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 N/A
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Masking
Single blind
Who is masked
Participant
Enrolment
100 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT02944253
Sponsor's protocol ID
2016/1297
Status last verified
Oct 2023
First submitted
21 Oct 2016
Last updated
4 Oct 2023
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
Undecided

Publications

  • Deemer SE, Plaisance EP, Martins C. Impact of ketosis on appetite regulation-a review. Nutr Res. 2020 May;77:1-11. doi: 10.1016/j.nutres.2020.02.010. Epub 2020 Feb 20.

    PubMed 32193016
  • Martins C, Roekenes J, Salamati S, Gower BA, Hunter GR. Metabolic adaptation is an illusion, only present when participants are in negative energy balance. Am J Clin Nutr. 2020 Nov 11;112(5):1212-1218. doi: 10.1093/ajcn/nqaa220.

    PubMed 32844188
  • Martins C, Roekenes J, Gower BA, Hunter GR. Metabolic adaptation is associated with less weight and fat mass loss in response to low-energy diets. Nutr Metab (Lond). 2021 Jun 11;18(1):60. doi: 10.1186/s12986-021-00587-8.

    PubMed 34116675
  • Martins C, Nymo S, Aukan MI, Roekenes JA, Coutinho SR, Hunter GR, Gower BA. Association between ss-Hydroxybutyrate Plasma Concentrations after Hypocaloric Ketogenic Diets and Changes in Body Composition. J Nutr. 2023 Jul;153(7):1944-1949. doi: 10.1016/j.tjnut.2023.05.010. Epub 2023 May 12.

    PubMed 37182692
  • Martins C, Roekenes J, Salamati S, Gower BA, Hunter GR. Reply to E Ravussin and L Redman. Am J Clin Nutr. 2020 Dec 10;112(6):1655-1656. doi: 10.1093/ajcn/nqaa309. No abstract available.

    PubMed 33301007
  • Martins C, Roekenes J, Hunter GR, Gower BA. Association between ketosis and metabolic adaptation at the level of resting metabolic rate. Clin Nutr. 2021 Aug;40(8):4824-4829. doi: 10.1016/j.clnu.2021.06.029. Epub 2021 Jul 6.

    PubMed 34358822

Questions about this trial

What is this clinical trial studying?

A study testing Low energy diet 70 gram carbohydrates, Low energy diet 100 gram carbohydrates and Low energy diet 130 gram carbohydrates in people with Obesity, run by Norwegian University of Science and Technology at 1 site in Norway.

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 4 inclusion and 12 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 4 Oct 2023. 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 Norway. 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.

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?

Suppression of appetite sensations measured using online visual analogue scales (time frame: 12 weeks (at start of study (baseline), at week 9 (after diet induced weight loss period), and week 13 (after weight stabilization period)). The study lists 4 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 NCT02944253, which also lists 6 linked publications.

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 4 Oct 2023.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in