Medium-Chain Triglycerides in Combination with Leucine and Vitamin D Benefit Cognition in Frail Elderly Adults: A Randomized Controlled Trial

Abstract

SummaryThe combined supplementation of medium-chain triglycerides (MCTs), l-leucine-rich amino acids, and cholecalciferol (vitamin D3) increase muscle strength and function in frail elderly individuals. However, their effects on cognition are unknown. We enrolled 38 elderly nursing home residents (mean age6SD, 86.664.8 y) in a 3-mo randomized, controlled, parallel group trial. The participants were randomly allocated to 3 groups: the first group received a l-leucine (1.2 g)-and cholecalciferol (20 mg)-enriched supplement with 6 g of MCT (LD1MCT); the second group received the same supplement with 6 g of long-chain triglycerides (LD1LCT); and the third group did not receive any supplements (control). Cognition was assessed at baseline and after the 3-mo intervention. The difference in changes among the groups was assessed with ANCOVA, adjusting for age and the baseline value as covariates. After 3 mo, the Mini-Mental State Examination (MMSE) score in the LD1MCT group increased by 10.6% (from 16.6 to 18.4 points, p,0.05). After 3 mo, the Nishimura geriatric rating scale for mental status (NM scale) score in the LD1MCT group increased by 30.6% (from 24.6 to 32.2 points, p,0.001), whereas that in the LD1LCT and control groups decreased by 11.2% (from 31.2 to 27.7 points, p,0.05) and 26.1% (from 27.2 to 20.1 points, p,0.001), respectively. The combined supplementation of MCTs (6 g), l-leucine-rich amino acids, and cholecalciferol may improve cognitive function in frail elderly individuals.

Are ketogenic diets promising for Alzheimer’s disease? A translational review

“…However, the instruments used to assess cognitive outcomes were inconsistent among studies. Five studies used the Mini-Mental Status Examination [28,31,32,34,38], and four of them utilized the Alzheimer Disease Assessment Scale (ADAS-cog) [31,35,37,38]. Two studies used a neuroimaging (PET) endpoint: regional cerebral blood flow [30] or [11C]-acetoacetate tracer [28].…”

“…Three other studies did not show any significant weight change with KS [28,31,35]. Interestingly, Abe et al observed that participants improved their muscle mass and function [32]. Of note, those subjects received vitamin D and leucine in addition to the nutritional intervention, which may have contributed to this anabolic effect.…”

“…Besides inflammatory diseases, mood disorders, chronic pain and polypharmacy may change the nutritional status of the individuals, as well as the safety of a high-fat diet. Moreover, only Abe et al presented its exclusion criteria: subjects with body mass index < 23 kg/m 2 or major organ dysfunction [32]. Altogether, this impairs the external validity of the studies and pleads for new studies that would assess the interaction between comorbidities and KD/KS in patients.…”

“…Thus, the authors were able to demonstrate that ketosis was quickly and efficiently reached in all the studies, regardless of the type of intervention. However, only five studies examined the changes in nutritional status or body composition in patients under KS/KD [28,31,32,35,36]. Krikorian et al highlighted a mean weight loss of 4 kg per individual after 6 weeks, in MCI adults under KD as compared to patients under control diet [36].…”

Effects of Peppermint Essential Oil on Learning and Memory Ability in APP/PS1 Transgenic Mice

“…After sniffing peppermint essential oil, the above amino acid metabolites were up-regulated and close to the normal level. Among them, leucine has been reported to improve the cognitive function of the frail elderly when combined with vitamin D [ 23 ].…”