The purpose of the pilot clinical trial described herein is to determine the level of ketone production [measured as β hydroxybutyrate (BHB)] following consumption of (R)-1,3-butanediol in a beverage and to record gastrointestinal (GI) symptomology, as well as any effects on alertness/sleepiness.

Primary:

To evaluate the level of production of BHB following the consumption of 3 servings of Avela™, with consumption of each serving separated by 30 minutes and each serving providing 11.5 g of (R)-1,3-butanediol [total intake of 34.5 g of (R)-1,3-butanediol].

BHB levels will be measured using capillary whole blood from the fingertips using at home Keto-Mojo monitoring system (β-Ketone, as beta-hydroxybutyrate, in fingertip capillary whole blood).

Measurement Range: 0.1 - 8.0 mmol/L Measurement time (min): 0, 30, 60, 90, 120, 180, 240, 300

Secondary:

To evaluate the acute effects of 3 servings of Avela™, with consumption of each serving separated by 30 minutes and each serving providing 11.5 g of (R)-1,3-butanediol [i.e., total intake of 34.5 g (R)-1,3-butanediol] on: GI tolerance.

All subjects will complete the mVAS GI symptoms tool at baseline (0 minutes), and at 30, 60, 90, 120, 180, 240, and 300 minutes.

A validated tool to measure GI tolerability of (R)-1,3-butanediol will be utilized. The mVAS GI symptoms tool is a self-administered questionnaire, which is modeled after the validated "gold standard" measurement tool predominantly used to test clinical gastroenterology scenarios (Bengtsson et al., 2013).

Sleepiness/alertness The SSS (Shahid et al., 2012) is a subjective tool to assess how alert a subject is feeling at specific moments in time. The scale requires respondents to select a rating of 1 to 7, where a "1" indicates the subject is "feeling active, vital, alert, or wide awake" and the highest score of "7" indicates the subject is "no longer fighting sleep, sleep onset soon; having dream-like thoughts" (Hoddes et al., 1973). The scale is validated, correlating r = 0.68 with performance on the Wilkinson tests. All subjects will complete the SSS at baseline (0 minutes) and at 30, 60, 90, 120, 180, 240, and 300 minutes.

Inclusion Criteria:

• Males and females, 18 to 65 years of age
• BMI 18 to <35.0 kg/m2, inclusive
• Weight ≥ 110 lbs
• Subject is judged to be in good health on the basis of medical history
• Subject is willing to fast for 12 hours prior to study start
• Subject is willing to avoid alcohol and intense physical activity the day prior to and on the day of testing
• Subject is capable of giving informed consent and complying with all study procedures/requirements.

Exclusion Criteria:

• Previous GI disorders (e.g., inflammatory bowel disease, irritable bowel syndrome, history of surgery for weight loss, or gastroparesis)
• Gastroenteritis in the 2 weeks preceding the study
• Diabetes
• Weight <110 lbs
• History of alcohol or drug abuse
• Previous diagnosis of neurological disorders, depression, or mental illness with psychosis
• Unexplained alarm features (i.e., unintentional weight loss >10% body weight in the last 3 months, fevers, or blood in stools)
• Use of an antibiotic or any medication impacting gut transit during the 2 weeks before the study
• Constipation or diarrhea (defined as, on average, less than 3 stools per week or more than 3 stools per day, respectively)
• Allergy to tree nuts
• Women who are pregnant or breastfeeding
• Persons with medical conditions affecting the pancreas, liver, thyroid, or gall bladder.