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NCT Number: NCT06515717

Exogenous Ketones and Behavior

The study will examine the effect of exogenous ketone ester on behavior and metabolism using Virtual Reality and computerizes behavioral tasks.

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Key information

Conditions

Behavior Acid-Base Imbalance Acidosis Anxiety Disorders Ketosis Mental Disorders Metabolic Diseases Nutritional and Metabolic Diseases

Age range

18 year–45 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

German Institute of Human Nutrition

Potsdam, Brandenburg, 14558, Germany

Location status: Recruiting

Location contact

Bianca Weigel

CONTACT

[email protected]

+49 33200 882724

About this study

This study investigates the effects of exogenous ketone ester on behavior, cognition, and metabolism over one week of consumption. Using a within-subjects, randomized, crossover design, participants will undergo two phases: one with the ketone ester supplement and one with a calorie- and taste-matched placebo. The study includes four lab visits: visits 1 and 3 mark the first day of each intervention, while visits 2 and 4 mark the last day. During each visit, participants will complete behavioral tasks, questionnaires, and blood tests. Additionally, participants will record their food intake via an app and collect stool samples throughout the intervention.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Consent to participate
  • Fluent in German
  • Physically healthy. No regular medication
  • No drug use 1 week prior to the study
  • BMI 18-31 kg/m2

Exclusion criteria

  • Former or current illnesses of:
  • Brain or mind (including eating disorders, personality disorders, alcohol, drugs or drug dependence, neurological disorders other than occasional headache; depression or anxiety disorder excluded)
  • Heart or blood circulation
  • Gastro-intestinal or endocrine disorders
  • Liver or kidney disorders
  • Electrolyte imbalance
  • Other serious past or present medical conditions (for example, metabolic syndrome, diabetes, cancer)
  • Pregnancy
  • Extreme athletes (>2h/day intense work-out; casual cycling or walking is ok)
  • Menopause (post menopause is ok)
  • Ketogenic diet, ketogenic supplement intake, intermittent fasting or calorie restricted diet during preceding 4 weeks of study participation
  • Fear of blood draw

Treatment and study plan

Ketone ester

Dietary Supplement

oral supplement

dextrose (placebo)

Dietary Supplement

oral supplement calorie and taste matched to ketone supplement

Primary outcomes

  1. Anxiety behavior in Virtual Reality

    Time frame: on day 8 of each intervention arm (visit 2 and 4)

    Using different scenes in Virtual Reality, parameters of motion behavior such as speed (measured in meters per second) and distance walked (measured in meters) will be assessed using motion tracking technology. These measurements will be combined to generate a composite score of anxiety-related motion behavior.

  2. Risk propensity on a decision-making task

    Time frame: on day 8 of each intervention arm (visit 2 and 4)

    The choice (accept/reject) between a risk/gamble or safe option, based on a task paradigm by Liu et al. (2021)

  3. Competitive confidence in a competition task

    Time frame: on day 8 of each intervention arm (visit 2 and 4)

    based on a task paradigm by Goette et al., 2015

  4. Delay Discounting behavior in a computerized task

    Time frame: on day 1 of each intervention arm (visit 1 and 3)

    based on a task paradigm by Eisenstein et al. 2015

  5. Performance in Dual Task

    Time frame: on day 1 of each intervention arm (visit 1 and 3)

    based on a task paradigm by Szameitat et al., 2002

  6. Levels of ketones (ß-Hydroxybutyrate)

    Time frame: baseline, 15, 30, 60, and 90 minutes post drink-consumption on each of the 4 visits

    Blood samples

  7. Insulin

    Time frame: baseline, 15, 30, 60, and 90 minutes post drink-consumption on each of the 4 visits

    Blood samples

  8. Ghrelin

    Time frame: baseline and + 90 minutes post drink-consumption on each of the 4 visits

    Blood samples

  9. Glucose Values

    Time frame: every 15 Minutes from visit 1 to visit 2 and again from visit 3 to visit 4

    Continuous Glucose Monitoring through sensors applied to skin

  10. Blood Glucose

    Time frame: baseline, 15, 30, 60, and 90 minutes post drink-consumption on each of the 4 visits

    Blood samples

  11. Levels of cortisol

    Time frame: baseline, 15, 30, 60, and 90 minutes post drink-consumption on each of the 4 visits

    Blood samples

  12. Electrocardiogram (heart rate)

    Time frame: between 30 and 60 minutes post drink-consumption on each of the 4 visits

    Electrophysiological recording

  13. Electrocardiogram (heart rate variability)

    Time frame: between 30 and 60 minutes post drink-consumption on each of the 4 visits

    Electrophysiological recordings

  14. Electrodermal Activity

    Time frame: between 30 and 60 minutes post drink-consumption on each of the 4 visits

    Electrophysiological recordings

  15. Subjective anxiety levels

    Time frame: on day 8 of each intervention arm (visit 2 and 4)

    reported by participants on visual analog scale (1-7) during Virtual Reality. 1 being no anxiety to 7 being high anxiety

  16. Subjective stress levels

    Time frame: on day 8 of each intervention arm (visit 2 and 4)

    reported by participants on visual analog scale (1-7) during Virtual Reality. 1 being no stress to 7 being high stress

Secondary outcomes

  1. Gut microbiome

    Time frame: on day 8 of each intervention arm (visit 2 and 4)

    Assessed via stool samples after each intervention

  2. Daily food intake

    Time frame: 5 days of each intervention arm

    Self-reported food intake recorded via FoodApp or handwritten food diary

  3. Trait Anxiety Questionnaire

    Time frame: baseline before visit 1

    Trait version of State-Trait Anxiety Inventory (STAI; Grimm et al. 2009). High scores mean high trait anxiety.

  4. State Anxiety Questionnaire

    Time frame: on day 1 and 8 of each intervention arm (visit 1,2,3,4)

    State version of State-Trait Anxiety Inventory (STAI; Grimm et al. 2009). High scores mean high state anxiety.

  5. Interoception Questionnaire

    Time frame: on day 8 of each intervention arm (visit 2 and 4)

    Multidimensional Assessment of Interoceptive Awareness (MAIA; Bornemann et al. 2015). High scores mean high interoceptive ability.

  6. Depression Questionnaire

    Time frame: baseline, and on day 8 of each intervention arm (visit 1, 2, and 4)

    Becks Depression Inventar (BDI; Kühner et al. 2007). High scores mean high depression scores

  7. Mood Questionnaire

    Time frame: on day 1 and 8 of each intervention arm (visit 1,2,3,4)

    Positive and Negative Affect Schedule (PANAS; Janke et al. 2014). High score on positive scale mean high positive mood and high scores on negative scale mean high negative mood.

  8. Inhibition Questionnaire

    Time frame: baseline (visit 1)

    Behavioral Inhibition and Activation (BISBAS; Strobel et al. 2001). High scores on inhibition scale mean high inhibition and high scores on activation scale mean high activation.

  9. Impulsivity Questionnaire

    Time frame: baseline (visit 1)

    Barratt Impulsiveness Scale (BIS; Barratt et al. 1965). High scores mean high impulsivity.

  10. Social Anxiety Questionnaire

    Time frame: baseline, and on day 8 of each intervention arm (visit 1, 2, and 4)

    Liebowitz Social Anxiety Scale (Heimberg et al. 1999). High scores mean high scoial anxiety

  11. Flow Questionnaire

    Time frame: on day 1 of each intervention arm (visit 1 and 3)

    Flow state scale (FSS; Rheinberg et al. 2002) asked after Dual Task. High scores mean more flow experience during the dual task.

  12. Emotional Eating Questionnaire

    Time frame: baseline (visit 1)

    Salzburg Emotional Eating Scale (SEES; Meule et al. 2018)

  13. Stress Eating Questionnaire

    Time frame: baseline (visit 1)

    Salzburg Stress Eating Scale (SSES; Meule et al. 2018)

  14. Dominance Questionnaire

    Time frame: baseline, and on day 8 of each intervention arm (visit 1, 2, and 4)

    Social Dominance and Aggressive Dominance Scale (Kalma et al. 1993)

  15. Autonomy Questionnaire

    Time frame: on day 8 of each intervention arm (visit 2 and 4)

    Basic Psychological Need Satisfaction and Frustration Scale (BPNSNF; Heissel et al. 2019)

  16. Personality Questionnaire

    Time frame: baseline (visit 1)

    Big Five Inventory (BFI; John et al. 1991)

  17. Chronotype Questionnaire

    Time frame: baseline (visit 1)

    Morningness-Eveningness Questionnaire (MEQ; Horne & Östberg, 1976)

  18. Stress Questionnaire

    Time frame: baseline, and on day 8 of each intervention arm (visit 1, 2, and 4)

    Perceived Stress Questionnaire (PSQ; Fliege et al. 2001)

  19. Subjective anxiety levels

    Time frame: 5 days of each intervention arm

    reported via FoodApp once per day

  20. Subjective stress levels

    Time frame: 5 days of each intervention arm

    reported via FoodApp once per day

Study contacts

Contact information is provided by the study sponsor or research team.

Beatrix Keweloh

CONTACT

[email protected]

+49 33200 882518

Soyoung Q Park, Prof.

CONTACT

[email protected]

Sponsors and collaborators

Lead sponsor

German Institute of Human Nutrition

Other

Registry information

Official study title

Exogenous Ketones and Behavior (ExoKet)

Acronym: ExoKet

Important dates

Study start
2024
Primary completion
2025
Study completion
2025
First posted
Jul 23, 2024
Registry last updated
Jul 29, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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