Aged
Conditions
Brief summary
In a cross-over design, 15 participants, age 65-75, will be tested in six different arms in a randomised order. After a 12-hour fast participants will be served 2.5 dl coffee with 15 g cream + 30-50 g of different fatty acids, with or without 50 g glucose. Blood ketones and other biomarkers will be measured during 4 hours.
Detailed description
In the metabolic state ketosis, beta-hydroxybutyrate (BHB) and acetoacetate are synthesised from fatty acids in the liver, resulting in higher circulating levels. Ketosis can be induced by fasting or adherence to a low-carb-high-fat diet, but also by intake of-at least some-medium-chain-triglycerides (MCT). MCT are built from fatty acids with a chain of 6-12 carbon atoms. Caprylic acid (C8) is well known to be ketogenic, but the effect of lauric acid (C12)-constituting about 50% of coconut oil-is less clear. The aim of this study is to assess ketosis, as a combined effect of an extended overnight fast, and intake of coconut oil or C8, and to study how ketosis is affected by simultaneous glucose intake. Sunflower oil is used as control, expected to not break fasting ketosis, although not being ketogenic in itself. Some sunflower oil is also added to C8 to make that arm isocaloric with coconut oil, with a roughly similar proportion of MCT. Coffee with cream will be used as a vehicle, and although coffee has been reported to be mildly ketogenic, this effect is expected to be negligible and equally distributed between arms.
Interventions
OTHERCoconut oil
Coconut oil given in coffee with cream
DIETARY_SUPPLEMENTCaprylic acid
Caprylic acid given in coffee with cream
OTHERSunflower oil
Sunflower oil given in coffee with cream
OTHERGlucose
Glucose dissolved in water
Sponsors
Karolinska Institutet
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
65 Years to 75 Years
Healthy volunteers
Yes
Inclusion criteria
* Daily consumption of coffee * Written informed consent
Exclusion criteria
* Smoker * Weight \<50 kg * Diagnosed diabetes * History of heart disease * History of disease related to internal organs or metabolism * Experience of sensitive gut, or known intolerance to the test ingredients * Medication expected to affect glucose- or lipid-metabolism * Fasting during study or one month before * High intensity physical activity \> 3 times/week * Dementia * Severe psychiatric conditions * Hb\<125 g/L * Participation in other lifestyle intervention last 6 months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Concentrations of BHB, area under the curve, 0-4 h | 0, 15, 30, 45, 60, 75, 90, 120, 150, 180, 210, 240 (minutes) | BHB, measured in venous whole blood with a point-of-care meter |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Concentrations of BDNF / pro-BDNF | 0, 60, 120, 240 (minutes) | Brain-derived neurotrophic factor (BDNF) & pro-BDNF in serum (not measured in arm 2, 3 & 5) |
| Concentrations of glucose | 0, 60, 120, 180, 240 (minutes) | Glucose, laboratory analysis |
| Self-rated satiety | 240 (minutes) | Assessed by a 5-grade categorical hunger-scale in a questionnaire at the end of each testing session. Participants will be instructed to choose the most suitable description of their hunger: 1. Not hungry at all. 2. Modestly hungry. Lunch can wait. 3. It feels like the right time for lunch. Hunger appeared during the last hour. 4. Very hungry. Hunger appeared during the last hour. 5. Hungry or very hungry. Hunger has been palpable for more than one hour. Answers a, b & c will be interpreted as sufficient satiety. |
| Self-rated tolerance of beverage | 240 (minutes) | Assessed by a 4-grade categorical scale in a questionnaire at the end of each testing session: Did you experience any inconvenience (i.e. nausea, upset stomach), which you attribute to the beverage you were served today? 1. No 2. Yes, minor inconvenience. 3. Yes, moderate inconvenience. 4. Yes, major inconvenience. If the answer is b, c or d participants are asked to give a short description. |
| Concentrations of total ketones | 0, 30, 60, 120 (minutes) | BHB + acetoacetate, laboratory analyses from plasma |
| Concentrations of BHB (capillary) | 30, 60, 120 (minutes) | BHB, measured in capillary whole blood with a point-of-care meter, for exploratory comparisons. (not measured in arm 3 & 5) |
Other
| Measure | Time frame | Description |
|---|---|---|
| Concentrations of insulin | 0, 60, 90, 120, 240 (minutes) | Not measured at minutes 60, 90 & 120 in arm 1, 2, 4, 6 |
| Concentrations of glucagon | 0, 60, 90, 120, 240 (minutes) | Not measured at minutes 60, 90 & 120 in arm 1, 2, 4, 6 |
| Concentrations of HbA1c | 0 (minutes) | Only measured at the first testing session |
Countries
Sweden
Outcome results
None listed