Quantification of Ketosis After Intake of Coconut Oil and Caprylic Acid-With and Without Glucose-After a 12-hour Fast

Quantification of Ketosis After Intake of Coconut Oil and Caprylic Acid-With and Without Glucose-After a 12-hour Fast

Quantification of Ketosis After Intake of Coconut Oil and Caprylic Acid-With and Without Glucose-After a 12-hour Fast: A 6-way Cross-over Study in Healthy Older Adults

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.

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.

BHB, measured in capillary whole blood with a point-of-care meter, for exploratory comparisons. (not measured in arm 3 & 5)

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: Not hungry at all. Modestly hungry. Lunch can wait. It feels like the right time for lunch. Hunger appeared during the last hour. Very hungry. Hunger appeared during the last hour. Hungry or very hungry. Hunger has been palpable for more than one hour. Answers a, b & c will be interpreted as sufficient satiety.

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? No Yes, minor inconvenience. Yes, moderate inconvenience. Yes, major inconvenience. If the answer is b, c or d participants are asked to give a short description.

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

Norgren J, Daniilidou M, Kareholt I, Sindi S, Akenine U, Nordin K, Rosenborg S, Ngandu T, Kivipelto M, Sandebring-Matton A. Serum proBDNF Is Associated With Changes in the Ketone Body beta-Hydroxybutyrate and Shows Superior Repeatability Over Mature BDNF: Secondary Outcomes From a Cross-Over Trial in Healthy Older Adults. Front Aging Neurosci. 2021 Aug 20;13:716594. doi: 10.3389/fnagi.2021.716594. eCollection 2021.

Norgren J, Sindi S, Sandebring-Matton A, Kareholt I, Daniilidou M, Akenine U, Nordin K, Rosenborg S, Ngandu T, Kivipelto M. Ketosis After Intake of Coconut Oil and Caprylic Acid-With and Without Glucose: A Cross-Over Study in Healthy Older Adults. Front Nutr. 2020 Apr 15;7:40. doi: 10.3389/fnut.2020.00040. eCollection 2020.