Tolerability and Acceptability of an Exogenous Ketone Monoester and Ketone Monoester/Salt Formulation in Humans

Exogenous ketone ester and ketone ester mixed with ketone free acid formulations are rapidly entering the commercial marketspace. Short-term animal and human studies using these products suggest significant potential for primary or secondary prevention of a number of chronic disease conditions. However, a number of questions need to be addressed by the field for optimal use in humans, including variable responses among available exogenous ketones at different dosages; frequency of dosing; and their tolerability, acceptability, and efficacy in long-term clinical trials. The purpose of the current investigation was to examine the tolerability, acceptability, and circulating R-beta-hydroxybutyrate (R-βHB) and glucose responses to a ketone monoester (KME) and ketone monoester/salt (KMES) combination at 5 g and 10 g total R-βHB compared with placebo control (PC). Fourteen healthy young adults (age: 21 ± 2 years, weight: 69.7 ± 14.2 kg, percent fat: 28.1 ± 9.3%) completed each of the five study conditions: placebo control (PC), 5 g KME (KME5), 10 g KME (KME10), 5 g (KMES5), and 10 g KMES (KMES10) in a randomized crossover fashion. Circulating concentrations of R-βHB were measured at baseline (time 0) following an 8-12 h overnight fast and again at 15, 30, 60, and 120 min following drink ingestion. Participants also reported acceptability and tolerability during each condition. Concentrations of R-βHB rose to 2.4 ± 0.1 mM for KME10 after 15 min, whereas KMES10 similarly peaked (2.1 ± 0.1 mM) but at 30 min. KME5 and KMES5 achieved similar peak R-βHB concentrations (1.2 ± 0.7 vs. 1.1 ± 0.5 mM) at 15 min. Circulating R-βHB concentrations were similar to baseline for each condition by 120 min. Negative correlations were observed between R-βHB and glucose at the 30 min time point for each condition except KME10 and PC. Tolerability was similar among KME and KMES, although decreases in appetite were more frequently reported for KMES. Acceptability was slightly higher for KMES due to the more frequently reported aftertaste for KME. The results of this pilot investigation illustrate that the KME and KMES products used increase circulating R-βHB concentrations to a similar extent and time course in a dose-dependent fashion with slight differences in tolerability and acceptability. Future studies are needed to examine variable doses, frequency, and timing of exogenous ketone administration for individuals seeking to consume ketone products for health- or sport performance-related purposes.

Dietary ketone ester attenuates the accretion of adiposity and liver steatosis in mice fed a high-fat, high-sugar diet

Objective: The ketone diester, R,S-1,3-butanediol diacetoacetate (BD-AcAc2), attenuates the accretion of adiposity and reduces hepatic steatosis in high-fat diet-induced obese mice when carbohydrate energy is removed from the diet to accommodate energy from the ester. Reducing carbohydrate energy is a potential confounder due to the well-known effects of carbohydrate restriction on components of energy balance and metabolism. Therefore, the current investigation was designed to determine whether the addition of BD-AcAc2 to a high-fat, high-sugar diet (with no reduction in carbohydrate energy) would attenuate the accretion of adiposity and markers of hepatic steatosis and inflammation. Methods: Sixteen 11-week-old male C57BL/6J mice were randomized to one of two groups for 9 weeks (n = 8 per group): 1) Control (CON, HFHS diet) or 2) Ketone ester (KE, HFHS diet + BD-AcAc2, 25% by kcals). Results: Body weight increased by 56% in CON (27.8 ± 2.5 to 43.4 ± 3.7 g, p < 0.001) and by 13% in KE (28.0 ± 0.8 to 31.7 ± 3.1 g, p = 0.001). Non-alcoholic fatty liver disease activity scores (NAS) for hepatic steatosis, inflammation, and ballooning were lower in the KE group compared to CON (p < 0.001 for all). Markers of hepatic inflammation [Tnfα (p = 0.036); Mcp1 (p < 0.001)], macrophage content [(Cd68 (p = 0.012)], and collagen deposition and hepatic stellate cell activation [(αSma (p = 0.004); Col1A1 (p < 0.001)] were significantly lower in the KE group compared to CON. Conclusion: These findings extend those of our previous work and show that BD-AcAc2 attenuates the accretion of adiposity and reduces markers of liver steatosis, inflammation, ballooning, and fibrosis in lean mice placed on a HFHS diet where carbohydrate energy was not removed to accommodate energy from addition of the diester.

Evaluation of physical health effects due to volcanic hazards: crystalline silica in Mount St. Helens volcanic ash

This investigation has shown that crystalline silica has been identified as being present in the Mount St. Helens volcanic ash at levels of 3 to 7 per cent by weight. This identification has been established using X-ray powder diffraction, infrared spectrophotometry, visible spectrophotometry, electron microscopy, and Laser Raman spectrophotometry. Quantitative analysis by IR, XRD, and visible spectrophotometry requires a preliminary phosphoric acid digestion of the ash sample to remove the plagioclase silicate material which interferes with the determination by these methods. Electron microscopic analysis as well as Laser Raman spectrophotometric analysis of the untreated ash confirms the presence of silica and at levels found by the XRD and IR analysis of the treated samples. An interlaboratory study of volcanic ash samples by 15 laboratories confirms the presence and levels of crystalline silica. Although several problems with applying the digestion procedure were observed in this hastily organized supply, all laboratories employing the digestion procedure reported the presence of crystalline silica. These results unequivocally put to rest the question of the presence of silica in the volcanic ash from eruptions of Mount St. Helens in 1980.