BIKE Study

Ketone Ester (BIKE) Study CLOSED

The safety and tolerance of ketone drinks in older adults


Ketones are naturally occurring compounds that are made by your liver. You have a small amount in your blood at any given time. Your liver breaks down fat and turns fat into ketones which then supply your body with energy. Ketones increase when you do not eat enough sugar to provide energy to maintain your body. One way to make your liver produce ketones is by following a ketogenic diet composed of high fat and low sugar foods. Previous scientific research has shown that being in a ketone-producing state may provide positive benefits including improved metabolic health, cognition and endurance exercise performance. However, generating ketones through diet alone can be challenging for some people to start and/or maintain long-term due to the limited food options the diet allows.

Researchers are looking to deliver the benefits of ketones without needing to follow strict and challenging diets. One way to do this is by consuming products that contain ketone esters. How ketone esters specifically affect older adults requires investigation. To do this, researchers seek older (≥65 years old) subjects to regularly consume a study beverage containing one type of ketone ester (C8 Ketone Di-ester), a ketone compound that is produced outside of the body but that is turned into ketones naturally after eating. The goal of this study is to determine the safety of daily consumption of ketone ester beverages in older adults.

Participants: Healthy people at, or over the age of 65
Location: The Buck Institute, Novato, CA
Dates: Study started December 2022, estimated completion December 2023
Duration: Participation in the study will last approximately 4 months
Compensation: Compensation of up to $500 is offered for the completion of this study
Status: No longer recruiting
Start date: December 2022
End date: December 2023 (estimated)
Sponsor: The Buck Institute for Research on Aging, through a gift by Dr James B Johnson, MD. 
ID:  NCT05585762
Study type: Randomized, parallel group, double blinded
Participants: 30 participants
Last updated: September 6th 2023

Number of visits:

  • One screening visit in clinic
  • 4 study visits in clinic

List of study procedures:

  • Medical history
  • Height, weight, waist circumference
  • Vital signs (pulse and blood pressure, etc)
  • Fasting blood work
  • Urine sampling in clinic
  • Daily consumption of study drink at home for 12 weeks
  • Study questionnaires
  • Physical activity monitoring (FitBit)
  • Physical tests (balance, walking, strength, etc)
  • Mental tests (memory, cognition, etc).
  • Ketone and glucose monitoring (in clinic and at home).
  • Stool sample collection

You can join if you…

  • are 65 years of age or older
  • have a BMI between 18.5 – 34.9 k/m2
  • are living independently
  • have no medical conditions that have changed recently or medication use that has changed recently
  • have a Bluetooth enabled smart phone and access to the internet

You can’t join if…

  • you live in a setting where you receive assistance with your activities of daily living
  • your medical history, medication/supplement list or screening blood tests show a condition or recent changes that means that the medical officer decides it is not safe for you to participate
  • you have a cognitive condition that means you cannot give informed consent to take part
  • you have an allergy to milk or soy
  • you follow a strict diet (such as ketogenic diet)

John Newman, MD, PhD

John Newman, MD, PhD, is an Assistant Professor at the Buck Institute for Research on Aging and an Associate Professor in the Division of Geriatrics at University of California San Francisco (UCSF). His career goal is to translate our expanding understanding of aging biology to improve the care and help maintain the independence of older adults. His research at the Buck Institute studies the molecular details of how diet and fasting regulate the genes and pathways that in turn control aging, focusing on the ketone body beta-hydroxybutyrate and how its molecular signaling activities involving epigenetics and inflammation regulate aging and memory in mice. 

Dr. Newman is also a geriatrician who cares for hospitalized older adults at UCSF and the San Francisco VA Medical Center, focusing on preserving mobility and preventing delirium.


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