Mechanistic Effect of Ketones on Cerebral Blood Flow (MEKC)

McMaster University

Status: Completed

Conditions: Cerebrovascular Function; Cerebral Blood Flow

Treatments: Dietary Supplement: Normocapnia; Dietary Supplement: Poikilocapnia

Study type: Interventional

Funder types: Other

Identifiers

NCT06217159

MEKC

Details and patient eligibility

About

Oral supplements containing exogenous ketones have recently become available and represent a novel tool for increasing plasma ketone bodies without the need for dietary restriction. Early evidence suggests that oral ketone supplements may enhance cerebral blood flow (CBF). However, a higher dose of a ketone monoester has been shown to slightly lower blood pH and reduce end-tidal CO2 (PetCO2) due to compensatory hyperventilation, which is accompanied by parallel reductions in CBF. Whether reductions in PetCO2 causes reductions in CBF is currently unknown.

The purpose of this study is to investigate the effect of manipulating PetCO2 at normocapnia (PetCO2 maintained at baseline) or poikilocapnia (no PetCO2 targeting; breathing room air), following the ingestion of a dose of a ketone monoester on CBF and cerebrovascular reactivity to CO2 in young adults.

Enrollment: 23 patients

Sex: All

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Having a normal blood pressure (≤125/≤85 mmHg)
• Between the ages of 18 and 35

Exclusion criteria

• Individuals who are obese (body mass index > 30 kg/m^2)
• Individuals who smoke
• Individuals with respiratory illnesses
• A history of type 2 diabetes, hypoglycemia, or cardiovascular diseases (i.e. heart attack, stroke)
• Individuals currently following a ketogenic diet or taking ketone supplements
• Individuals with a history of concussion(s) with persistent symptoms
• Individuals participating in elite-level physical training (i.e. varsity athletics)

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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23 participants in 2 patient groups

Poikilocapnia

Sham Comparator group

Description:

Room air-breathing

Treatment:

Dietary Supplement: Poikilocapnia

Normocapnia

Experimental group

Description:

Breathing air mixture with slightly elevated CO2 to maintain PetCO2 to resting baseline levels

Treatment:

Dietary Supplement: Normocapnia