Dietary medium-chain triacylglycerols versus long-chain triacylglycerols for body composition in adults: systematic review and meta-analysis of randomized controlled trials

Possible Extracellular Signals to Ameliorate Sarcopenia in Response to Medium-Chain Triglycerides (8:0 and 10:0) in Frail Older Adults

In frail older adults (mean age 85 years old), a 3-month supplementation with a low dose (6 g/day) of medium-chain triglycerides (MCTs; C8:0 and C10:0) given at a meal increased muscle mass and function, relative to supplementation with long-chain triglycerides (LCTs), but it decreased fat mass. The reduction in fat mass was partly due to increased postprandial energy expenditure by stimulation of the sympathetic nervous system (SNS). However, the extracellular signals to ameliorate sarcopenia are unclear. The following three potential extracellular signals to increase muscle mass and function after MCT supplementation are discussed: (1) Activating SNS-the hypothesis for this is based on evidence that a beta2-adrenergic receptor agonist acutely (1-24 h) markedly upregulates isoforms of peroxisomal proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) mRNAs, promotes mitochondrial biogenesis, and chronically (~1 month) induces muscle hypertrophy. (2) An increased concentration of plasma acyl-ghrelin stimulates growth hormone secretion. (3) A nitrogen-sparing effect of ketone bodies, which fuel skeletal muscle, may promote muscle protein synthesis and prevent muscle protein breakdown. This review will help guide clinical trials of using MCTs to treat primary (age-related) sarcopenia.

The impact of medium-chain triglycerides on weight loss and metabolic health in individuals with overweight or obesity: A systematic review and meta-analysis

BACKGROUNDS

The efficacy of medium-chain triglycerides (MCTs) for weight management and mitigating metabolic disorders among individuals with overweight and obesity remains a topic of ongoing discussion. Notably, there is a gap in the distinction between pure MCTs and medium-long-chain triglycerides (MLCTs).

METHODS

This meta-analysis investigates the efficacy of MCTs on weight loss and glucolipid metabolism in these populations, explicitly evaluating the differential effects of pure MCTs and MLCTs. We performed a random-effects meta-analysis on relevant studies examining weight loss and glucolipid parameters, incorporating a subgroup analysis conducted based on intervention types, pure MCTs versus MLCTs.

RESULTS

Our findings revealed diets enriched with MCTs are more effective in achieving weight reduction (WMD: -1.53%; 95% CI: -2.44, -0.63; p < 0.01), particularly those containing pure MCTs (WMD: -1.62%; 95% CI: -2.78, -0.46; p < 0.01), compared to long-chain fatty acids (LCTs) enriched diets. However, our subgroup analysis indicates that an MLCTs-enriched diet did not significantly reduce weight loss. Additionally, MCTs-enriched diets were associated with significant reductions in blood triglyceride levels and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) scores, compared to LCTs-enriched diets.

CONCLUSIONS

Hence, the authors recommend incorporating pure MCTs in dietary interventions for individuals with overweight and obesity, particularly those with comorbidities such as dyslipidemia and impaired glucose metabolism.

Medium-chain triglycerides (8:0 and 10:0) increase muscle mass and function in frail older adults: a combined data analysis of clinical trials

Background

Three clinical trials have examined the chronic effects of medium-chain triglycerides (MCTs) on muscle mass and function in frail older adults (mean age 85 years old). However, significant increases in muscle mass and some muscle function relative to long-chain triglycerides (LCTs) have yet to be shown, possibly due to the small number of participants in each trial.

Objective

We re-analyzed these previous clinical trials to clarify whether MCT supplementation can increase muscle mass and function.

Analysis

After adding post hoc tests to the original report, we compared changes in measurement between the MCT and LCT groups in the first 2 trials and conducted a combined data analysis.

Methods

In a combined data analysis, changes from baseline in measurements at the 3 months intervention in the MCTs- and LCTs-containing groups were assessed by analysis of covariance adjusted for baseline values of each measurement, age, sex, BMI, allocation to trial, habitual intakes in energy, protein, leucine, octanoic acid, decanoic acid, and vitamin D during the baseline period. The Mann-Whitney U test was used to analyze data on right and left knee extension times.

Results

MCT supplementation for 3 months increased muscle function relative to LCT supplementation with and without an L-leucine (1.2 g) and vitamin D (cholecalciferol, 20 μg)-enriched supplement. In a combined data analysis (n = 29 in MCTs, n = 27 in LCTs), relative to supplementation with 6 g LCTs/day, supplementation with 6 g MCTs/day at dinner for 3 months significantly increased body weight (adjusted mean change from baseline: MCTs 1.2 vs. LCTs 0.2 kg, p = 0.023), right arm muscle area (MCTs 1.4 vs. LCTs-0.7 cm2, p = 0.002), left calf circumference (p = 0.015), right-hand grip strength (MCTs 1.6 vs. LCTs 0.3 kg, p = 0.017), right knee extension time (p = 0.021), left knee extension time (p = 0.034), walking speed (p = 0.002), and number of iterations in leg open and close test (p < 0.001) and decreased right triceps skinfold thickness (p = 0.016).

Conclusion

In frail older adults, supplementation for 3 months with a low dose (6 g/day) of MCTs (C8:0 and C10:0) increased muscle mass and function. These findings indicate the potential for the practical use of MCTs in daily life in treating sarcopenia.

Effects of ketone bodies on energy expenditure, substrate utilization, and energy intake in humans

The potential of ketogenic approaches to regulate energy balance has recently gained attention since ketones may influence both energy expenditure and energy intake. In this narrative review, we summarized the most relevant evidence about the role of ketosis on energy expenditure, substrate utilization, and energy intake in humans. We considered different strategies to induce ketosis, such as fasting, dietary manipulation, and exogenous ketone sources. In general, ketosis does not have a major influence on energy expenditure but promotes a shift in substrate utilization towards ketone body oxidation. The strategies to induce ketosis by reduction of dietary carbohydrate availability (e.g., ketogenic diets) do not independently influence energy intake, being thus equally effective for weight loss as diets with higher carbohydrate content. In contrast, the intake of medium-chain triglycerides and ketone esters induces ketosis and appears to increase energy expenditure and reduce energy intake in the context of high carbohydrate availability. These latter strategies lead to slightly enhanced weight loss. Unfortunately, distinguishing the effects of the various ketogenic strategies per se from the effects of other physiological responses is not possible with the available human data. Highly controlled, inpatient studies using targeted strategies to isolate the independent effects of ketones are required to adequately address this knowledge gap.

A Randomized, Double-Blind, Controlled Trial Assessing If Medium-Chain Triglycerides in Combination with Moderate-Intensity Exercise Increase Muscle Strength in Healthy Middle-Aged and Older Adults

An adequate nutritional intake is recommended for the prevention of physical frailty and sarcopenia. In particular, medium-chain fatty acids (MCFAs) are reportedly important for muscle strength in nursing home residents. However, the effects of MCFAs on healthy adults at risk for frailty remain unknown. Hence, a randomized, placebo-controlled study was conducted to investigate the effects of 12 weeks of medium-chain triglycerides (MCTs) intake and walking on muscle mass and function in healthy, sedentary, middle-aged and older adults with a low body mass index. Three MCT intake groups with different amounts of octanoic and decanoic acid intake were compared with a control group. After 12 weeks, knee extension strength increased in all groups, with the increases in all MCT intake groups being significantly higher than those in the control group (p < 0.05). Grip strength significantly increased from baseline in the MCT 6 g/day intake group (p < 0.05). The combination of aerobic exercise and MCT intake may be effective in preventing decline in muscle strength and promoting increase in muscle strength as they can improve muscle energy production, thereby contributing to the maintenance of good health for middle-aged and older adults at high risk for frailty and sarcopenia.

Supplementation with medium-chain fatty acids increases body weight loss during very low-calorie ketogenic diet: a retrospective analysis in a real-life setting

BACKGROUND

Very low-calorie ketogenic diet (VLCKD) has shown to significantly reduce body weight and fat mass, as well as inflammation. These effects are supported by nutritional ketosis, which triggers the utilization of the ketone body as an energy source. Medium-chain fatty acids (MCTs) might serve as potential enhancers of ketone bodies production with a greater effect on weight loss. Nevertheless, no clinical studies have evaluated the effect of MCTs supplementation in addition to VLCKD. Therefore, the present study aimed to evaluate whether the supplementation with MCTs can induce a greater weight reduction during the ketogenic phase of VLCKD.

METHODS

In this retrospective study, 263 women with overweight/obesity (body mass index, BMI: 35.7 ± 5.3 kg/m²) aged 37.5 ± 14.2 years followed one of these dietary protocols for 45 days: (a) Control group, 83 participants (31.6%) (VLCKD without MCTs), (b) VLCKD + MCTs group, 86 participants (32.7%) (MCTs supplementation - 20 g/day- during VLCKD starting from the first day of the active phase), (c) VLCKD + earlyMCTs, 94 participants (35.7%) (MCTs supplementation - 20 g/day-starting from 5 days before the beginning of the VLCKD active phase. Anthropometric measures, body composition, and c-reactive protein (CRP) concentrations were collected at the beginning and at the end (45 days) of the VLCKD intervention.

RESULTS

MCTs supplementation significantly decreased body weight, BMI, and waist circumference as compared to the control group, with a greater effect in the VLCKD + earlyMCTs group. A two-fold decrease in fat mass and an increase in muscle mass were observed in the VLCKD + earlyMCTs group as compared to the control group. As for inflammation, hs-CRP concentrations (assessed as absolute percent change) were significantly lower in the VLCKD + MCTs group (p = 0.009) and the VLCKD + earlyMCTs group (p = 0.011) than in the control group. A logistic regression model showed that VLCKD + earlyMCTs increase the likelihood of improvement of BMI classes (OR: 1.85, 95% CI 1.02-3.36) also after adjusting for the potential confounding factors.

CONCLUSION

MCTs supplementation (20 g/day) may be a useful tool to enhance the beneficial effect of VLCKD on the reduction of body weight and fat mass. In particular, MCTs supplementation before the beginning of the VLCKD active phase might facilitate ketosis thus contributing to the effectiveness of the nutritional intervention.

Role Medium-Chain Fatty Acids in the Lipid Metabolism of Infants

Human breastmilk, the ideal food for healthy infants, naturally contains a high concentration of medium-chain fatty acids (MCFAs, about 15% of total fatty acids). MCFAs are an important energy source for infants due to their unique digestive and metabolic properties. MCFA-enriched oils are widely used in an infant formula, especially the formula produced for preterm infants. Recently, there has been a growing interest in the triglyceride structure of MCFAs in human milk, their metabolism, and their effects on infant health. This study summarized the MCFA composition and structure in both human milk and infant formula. Recent studies on the nutritional effects of MCFAs on infant gut microbiota have been reviewed. Special attention was given to the MCFAs digestion and metabolism in the infants. This paper aims to provide insights into the optimization of formulations to fulfill infant nutritional requirements.

Applications of Medium-Chain Triglycerides in Foods

In the 1950s, the production of processed fats and oils from coconut oil was popular in the United States. It became necessary to find uses for the medium-chain fatty acids (MCFAs) that were byproducts of the process, and a production method for medium-chain triglycerides (MCTs) was established. At the time of this development, its use as a non-fattening fat was being studied. In the early days MCFAs included fatty acids ranging from hexanoic acid (C6:0) to dodecanoic acid (C12:0), but today their compositions vary among manufacturers and there seems to be no clear definition. MCFAs are more polar than long-chain fatty acids (LCFAs) because of their shorter chain length, and their hydrolysis and absorption properties differ greatly. These differences in physical properties have led, since the 1960s, to the use of MCTs to improve various lipid absorption disorders and malnutrition. More than half a century has passed since MCTs were first used in the medical field. It has been reported that they not only have properties as an energy source, but also have various physiological effects, such as effects on fat and protein metabolism. The enhancement of fat oxidation through ingestion of MCTs has led to interest in the study of body fat reduction and improvement of endurance during exercise. Recently, MCTs have also been shown to promote protein anabolism and inhibit catabolism, and applied research has been conducted into the prevention of frailty in the elderly. In addition, a relatively large ingestion of MCTs can be partially converted into ketone bodies, which can be used as a component of "ketone diets" in the dietary treatment of patients with intractable epilepsy, or in the nutritional support of terminally ill cancer patients. The possibility of improving cognitive function in dementia patients and mild cognitive impairment is also being studied. Obesity due to over-nutrition and lack of exercise, and frailty due to under-nutrition and aging, are major health issues in today's society. MCTs have been studied in relation to these concerns. In this paper we will introduce the results of applied research into the use of MCTs by healthy subjects.

Effect of dairy intake with or without energy restriction on body composition of adults: overview of systematic reviews and meta-analyses of randomized controlled trials

CONTEXT

Some studies suggest that consumption of dairy products can aid in weight loss, while others suggest a negative effect or no effect.

OBJECTIVE

An overview of systematic reviews and meta-analyses was conducted to examine the effect of dairy product consumption on changes in body composition.

DATA SOURCES

PRISMA guidelines were followed to ensure transparent reporting of evidence. The MEDLINE, Embase, Cochrane Central Database of Systematic Reviews, and Web of Science databases were searched from inception to April 2018.

STUDY SELECTION

Six systematic reviews and 47 associated meta-analyses (which included the results of 58 different randomized controlled trials) published in English or Spanish and reporting data on dairy intake and changes in weight, fat mass, lean mass, or waist circumference were included.

DATA EXTRACTION

Two authors independently extracted the data and assessed the risk of bias using the AMSTAR2 tool.

RESULTS

Dairy consumption interventions without dietary energy restriction had no significant effects on weight, fat mass, lean mass, or waist circumference. Interventions in energy-restricted settings had significant effects on fat mass and body weight.

CONCLUSIONS

Increasing total dairy intake without energy restriction in adults does not affect body composition. In the context of an energy-restricted diet, however, increased dairy intake results in lower fat mass and body weight but has no conclusive effects on waist circumference or lean mass.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42018094672.

Medium-chain triglycerides (8:0 and 10:0) are promising nutrients for sarcopenia: a randomized controlled trial

BACKGROUND

The combined supplementation of medium-chain triglycerides (MCTs), l-leucine-rich amino acids, and cholecalciferol was previously shown to increase muscle strength and function in frail elderly individuals.

OBJECTIVE

We examined whether treatment with MCTs alone is sufficient to increase muscle strength and function and activities of daily living (ADL) in such individuals.

METHODS

We enrolled 64 elderly nursing home residents (85.5 ± 6.8 y) in a 3-mo randomized, controlled, single-blinded intervention trial. The participants were randomly assigned to 3 groups: the first group received supplemental l-leucine (1.2 g) and cholecalciferol (20 μg) enriched with 6 g/d of MCTs (LD + MCT group) as a positive control, the second group received 6 g/d of MCTs (MCT group) as a target, and the third group received 6 g/d of long-chain triglycerides (LCT group) as a negative control. Changes in muscle mass, strength, function, and ADL were monitored 4 times: at baseline, at 1.5 and 3 mo after initiation of the intervention (intervention), and 1.5 mo after termination of the intervention (washout).

RESULTS

The 64 participants randomly assigned to the 3 groups were included in an intention-to-treat analysis. Forty-eight participants completed the study and were included in a per-protocol analysis. At 3 mo, participants in the MCT group had a 48.1% increase in 10-s leg open and close test performance [intention-to-treat adjusted means: MCT 2.28 n/10 s (1.37, 3.19) compared with LCT -0.59 n/10 s (-1.52, 0.35), P < 0.05], a 27.8% increase in a 30-s repetitive saliva swallowing test [MCT 0.5 n/30 s (0.1, 1.0) compared with LCT -0.5 n/30 s (-0.9, 0.0), P < 0.05], and a 7.5% increase in Functional Independence Measure score, a questionnaire for assessing ADL [MCT 5.6 points (1.3, 9.9) compared with LCT -6.6 points (-11.3, -2.0), P < 0.05].

CONCLUSION

MCTs (6 g/d) could increase the muscle strength and function of frail elderly individuals and also improve their ADL. This trial was registered at the University Hospital Medical Information Network Clinical Trial Registry as UMIN000023302.

The impact of dietary fatty acids on human adipose tissue

Nutrition is a major variable factor in human environments. The composition of nutrients has changed markedly in recent decades which may contribute to the increased prevalence of metabolic diseases, such as obesity and type 2 diabetes. Fat is an important component of the diet which comes in various forms with fatty acids (FA) of different carbon chain lengths and saturation degrees. In addition to being an energy supply, FA function as potent signalling molecules and influence transcriptional activity. Among other tissues, dietary FA target white adipose tissue function, which is central in maintaining metabolic health. This review focuses on the possible role of dietary FA composition and its effect on human white adipose tissue expandability and transcriptional response. Altogether, the existing literature suggests that unsaturated fat has more benign effects on adipose tissue distribution when compared to long-chain saturated fat. However, the mechanisms of action remain poorly characterised.

Lipid-Lowering Effects of Medium-Chain Triglyceride-Enriched Coconut Oil in Combination with Licorice Extracts in Experimental Hyperlipidemic Mice

Coconut oil has gained in popularity over recent years as a healthy oil due to its potential cardiovascular benefits. Coconut oil contains medium chain triglycerides (MCT) including lauric acid and capric acid that display beneficial properties in human health. Licorice ( Glycyrrhiza uralensis) is used as a sweetener and in traditional Chinese medicine with anti-inflammatory, antimicrobial, and antioxidant activities. This study investigated the in vivo effects of medium chain-triglycerides (MCT)-coconut oil (MCO) and its combination with licorice extract (LE-MCO) on serum lipid profile, hepatic steatosis, and local fat pad proteins in diet-induced obese mice. No liver toxicity was observed in 45% fat diet (HFD)-fed mice orally treated with LE, MCO, and LE-MCO for 12 weeks. Their supplementation reduced HFD-enhanced body weight, blood glucose, and insulin in mice. Plasma levels of both PLTP and LCAT were boosted in LE-MCO-administered mice. Supplementation of LE-MCO diminished plasma levels of TG and TC with concomitant reduction of the LDL-C level and tended to raise blood HDL-C level compared to that of HFD alone-mice. Treatment of LE-MCO encumbered the hepatic induction of hepatosteatosis-related proteins of SREBP2, SREBP1c, FAS, ACC, and CD36 in HFD-fed mice. Substantial suppression of this induction was also observed in the liver of mice treated with MCO. Oral administration of LE-MCO to HFD mice boosted hepatic activation of AMPK and the induction of UCP-1 and FATP1 in brown fat. Conversely, LE-MCO disturbed hepatic PPAR-LXR-RXR signaling in HFD-fed animals and reversed HFD-elevated epididymal PPARγ. Collectively, oral administration of LE-MCO may impede hyperlipidemia and hepatosteatosis through curtailing hepatic lipid synthesis.

Yogurt and Cardiometabolic Diseases: A Critical Review of Potential Mechanisms

Associations between yogurt intake and risk of diet-related cardiometabolic diseases (CMDs) have been the subject of recent research in epidemiologic nutrition. A healthy dietary pattern has been identified as a pillar for the prevention of weight gain and CMDs. Epidemiologic studies suggest that yogurt consumption is linked to healthy dietary patterns, lifestyles, and reduced risk of CMDs, particularly type 2 diabetes. However, to our knowledge, few to no randomized controlled trials have investigated yogurt intake in relation to cardiometabolic clinical outcomes. Furthermore, there has been little attempt to clarify the mechanisms that underlie the potential beneficial effects of yogurt consumption on CMDs. Yogurt is a nutrient-dense dairy food and has been suggested to reduce weight gain and prevent CMDs by contributing to intakes of protein, calcium, bioactive lipids, and several other micronutrients. In addition, fermentation with bacterial strains generates bioactive peptides, resulting in a potentially greater beneficial effect of yogurt on metabolic health than nonfermented dairy products such as milk. To date, there is little concrete evidence that the mechanisms proposed in observational studies to explain positive results of yogurt on CMDs or parameters are valid. Many proposed mechanisms are based on assumptions that commercial yogurts contain strain-specific probiotics, that viable yogurt cultures are present in adequate quantities, and that yogurt provides a minimum threshold dose of nutrients or bioactive components capable of exerting a physiologic effect. Therefore, the primary objective of this review is to investigate the plausibility of potential mechanisms commonly cited in the literature in order to shed light on the inverse associations reported between yogurt intake and various cardiometabolic health parameters that are related to its nutrient profile, bacterial constituents, and food matrix. This article reviews current gaps and challenges in identifying such mechanisms and provides a perspective on the research agenda to validate the proposed role of yogurt in protecting against CMDs.

[What is Result: Short-term Medium Chain Triglyceride Diet Effective on Postoperative Outcome in Lung Cancer Surgery? A Prospective Randomized Study]

背景与目的

中链甘油三酯(medium chain triglyceride, MCT)饮食有助于外科手术患者快速康复，本研究将短期MCT食谱应用于肺癌患者术后早期饮食，探讨肺癌患者术后应用MCT的临床效果。

方法

2015年12月-2016年3月四川大学华西胸外科单个医疗组肺癌切除术患者纳入研究患者117例，随机分为MCT组(62例)和常规饮食组(routine diet group, RDG)(55例)。分析两组患者术后白蛋白、肛门排气时间、胸腔闭式引流量及胸腔闭式引流管留置时间、术后住院日、住院费用。

结果

MCT组患者术后肛门排气时间[(27.87±14.38) h]短于RDG组[(45.18±8.62) h](P < 0.001)；术后胸腔引流管留置时间在MCT组[(75.40±48.41) h]少于RDG组[(110.64±94.19) h](P=0.025)；术后胸腔引流量在MCT[395mL]组少于RDG组[590mL](P=0.027)。术后住院日在MCT组[(5.26±2.96) d)]短于RDG组[(6.73±3.99) d](P=0.030)。血浆白蛋白术后MCT组[(37.26±2.70) g/L]高于RDG组[(35.92±3.12) g/L](P=0.023)。

结论

肺癌患者术后短期应用MCT饮食有助于改善胃肠功能快速恢复，且缩短术后住院时间。

The effects of proteins and medium-chain fatty acids from milk on body composition, insulin sensitivity and blood pressure in abdominally obese adults

BACKGROUND/OBJECTIVES

To investigate whether intake of whey protein and butter naturally enriched in medium-chain fatty acids (MC-SFAs) (C6-C12) affected body composition, insulin sensitivity, blood pressure (BP) and plasma cholesterol concentrations.

SUBJECTS/METHODS

A 12-week randomised, double-blinded, intervention study was completed in 52 abdominally obese adults. Subjects were assigned to one of four dietary supplementations: 63 g per day of milk fat with either high- (8.5 g per day) or low-MC-SFA (6.9 g per day) content combined with 60 g per day of whey or casein.We examined changes in the body composition by dual-energy X-ray absorption scan, insulin sensitivity using homoeostatic model assessment of insulin resistance (HOMA-IR) and Matsuda index, and diurnal BP and plasma cholesterol concentrations. Two-factor analysis of variance was used to examine the impact of MC-SFA content and protein type.

RESULTS

We observed that lean body mass increased by 981 g (95% confidence interval (CI): 248-1713; P=0.010) after high-MC-SFA compared with low-MC-SFA supplementation. Concomitantly, total body-fat percentage increased by 0.70 percentage points (95% CI: 0.10-1.31; P=0.024) after intake of low-MC-SFA butter compared with intake of high-MC-SFA butter. Both changes were independent of protein type (P=0.96 and P=0.99, respectively). We found no difference in HOMA-IR, Matsuda index, diurnal BP or plasma cholesterol concentrations related to MC-SFA content or protein type.

CONCLUSIONS

Enhanced intake of MC-SFA increased the lean body mass and caused a significantly lower total body-fat percentage compared with lower intake of MC-SFA. Consequently, the composition of dairy fat should be considered when evaluating the impact of dairy products on body composition.

Medium chain triglycerides (MCT) formulas in paediatric and allergological practice

Fats constitute the most significant nutritional source of energy. Their proper use by the body conditions a number of complex mechanisms of digestion, absorption, distribution, and metabolism. These mechanisms are facilitated by fats made of medium chain fatty acids; therefore, they are an easy and quick source of energy. Thus, an increased supply of medium chain triglycerides (MCT) is particularly important in patients with disturbances of digestion and absorption such as disturbed bile secretion, classic coeliac disease, short bowel syndrome, inflammatory diseases of the intestines, disturbed outflow of lymph, some metabolic disease, and severe food allergies, as well as in prematurely born neonates. Use of preparations containing an additive of MCT is limited, especially if they are to be used for a longer period of time. With a large quantity of MCT in a diet, there is a risk of deficiency of necessary unsaturated fatty acids and some fat-soluble vitamins. The caloricity of MTC compared to long-chain triglycerides is lower, and formulas with MCT are characterised by higher osmolality. Medium chain triglycerides is not recommended as an additive to standard formulas for healthy children. The use of MCT should be limited to strictly specified medical indications.

Medium-Chain Triglycerides in Combination with Leucine and Vitamin D Increase Muscle Strength and Function in Frail Elderly Adults in a Randomized Controlled Trial

BACKGROUND

Sarcopenia, the loss of skeletal muscle mass, strength, and function, is common in elderly individuals but difficult to treat.

OBJECTIVE

A combination of nutrients was investigated to treat sarcopenia in very frail elderly adults.

METHODS

We enrolled 38 elderly nursing home residents (11 men and 27 women with a mean ± SD age of 86.6 ± 4.8 y) in a 3-mo randomized, controlled, single-blind, parallel group trial. The participants were randomly allocated to 3 groups. The first group received a daily l-leucine (1.2 g) and cholecalciferol (20 μg)-enriched supplement with 6 g medium-chain triglycerides (TGs) (MCTs) (LD + MCT); the second group received the same leucine and cholecalciferol-enriched supplement with 6 g long-chain TGs (LD + LCT); and the third group did not receive any supplements (control). The supplement and oils were taken at dinner, and changes in muscle mass, strength, and function were monitored.

RESULTS

The increase in body weight in the LD + MCT (1.1 ± 1.0 kg) and LD + LCT (0.8 ± 1.1 kg) groups was greater than that in the control group (-0.5 ± 0.9 kg) (P < 0.05). After 3 mo, participants in the LD + MCT group had a 13.1% increase in right-hand grip strength (1.2 ± 1.0 kg, P < 0.01), a 12.5% increase in walking speed (0.078 ± 0.080 m/s, P < 0.05), a 68.2% increase in a 10-s leg open-and-close test performance (2.31 ± 1.68 n/10 s, P < 0.001), and a 28.2% increase in peak expiratory flow (53 ± 59 L/min, P < 0.01). No significant improvements in muscle mass, strength, or function were observed in the LD + LCT or control groups.

CONCLUSION

The combined supplementation of MCTs (6 g), leucine-rich amino acids, and cholecalciferol at dinner may improve muscle strength and function in frail elderly individuals. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry as UMIN000017567.

The diverse nature of saturated fats and the case of medium-chain triglycerides: how one recommendation may not fit all

PURPOSE OF REVIEW

The adverse cardiovascular health effects of saturated fats have been debated recently since the publication of studies reporting no increase in cardiovascular risk with saturated fat intakes. We purport that this may be because of the varied nature of saturated fats, which range in length from 2 to over 20 carbon atoms, and review evidence surrounding the cardiovascular health effects of medium-chain triglycerides (MCT).

RECENT FINDINGS

MCTs are saturated fats of shorter chain length than other, more readily consumed saturated fats. Studies have reported that consumption of MCT may lead to improvements in body composition without adversely affecting cardio-metabolic risk factors. There may also be synergistic actions between MCT and n-3 polyunsaturated fats that may lead to improvements in cardiovascular health.

SUMMARY

It is clinically relevant to distinguish between sources of saturated fats for cardiovascular health. Medium, and possibly shorter chain, saturated fats behave differently than long-chain saturated fats and should not be judged similarly when it comes to their cardio-metabolic health effects. Given their neutral, and potentially beneficial cardiovascular health effects, they should not be categorized together.