Older adults are at increased risk of malnutrition, for a variety of physiological and psychological reasons. This has implications for health, quality of life, independence and economic circumstances. Improvements in nutrition are known to bring tangible benefits to older people and many age-related diseases and conditions can be prevented, modulated or ameliorated by good nutrition. However, practical and realistic approaches are required to optimize diet and food intake in older adults. One area where improvements can be made relates to appetite. Encouraging older adults to prepare meals can increase appetite and food intake, and providing opportunities for older adults to eat a wide variety of foods, in company, is a simple strategy to increase food intake. The protein requirement of older adults is subject to controversy and although considered the most satiating macronutrient, it appears that protein does not elicit as great a satiating effect in older adults as it does in younger individuals. This indicates that there is potential to increase protein intake without impacting on overall energy intake. Other areas where simple practical improvements can be made include both packaging of foods that are easy to prepare and the education of older adults on the safe storage and preparation of food. Research into improving the diets and nutritional status of older adults has indicated that many of the strategies can be easily and cost-effectively undertaken.
Medium-chain triglycerides (MCT) are triglycerides with a fatty acid chain length varying between 6 and 10 carbon atoms. MCT differ from long-chain triglycerides as they are relatively soluble in water and, hence, rapidly hydrolysed and absorbed. MCT are transported in the blood through the portal system, consequently they bypass adipose tissue that makes them less susceptible to hormone-sensitive lipase and deposition into adipose tissue stores. Due to these properties, MCT have been researched for both benefits to exercise performance and health. The present review aims to assess whether MCT are beneficial in either of these situations. MCT have been proposed as a means to maximizing an athlete's ability to maintain their glycogen stores so they can be more competitive. However, only two studies to date have shown an improvement in exercise performance. From a health perspective, MCT increase fat oxidation and energy expenditure as well as reduce food intake and beneficially alter body composition. Results indicate that MCT feeding is ineffective in improving exercise performance and future work should focus on the health benefits and applications of MCT.
It is well established that the consumption of medium-chain triglycerides (MCT) can increase satiety and reduce food intake. Many media articles promote the use of coconut oil for weight loss advocating similar health benefits to that of MCT. The aim of this study was to examine the effect of MCT oil compared to coconut oil and control oil on food intake and satiety. Following an overnight fast, participants consumed a test breakfast smoothie containing 205kcal of either (i) MCT oil (ii) coconut oil or (iii) vegetable oil (control) on three separate test days. Participants recorded appetite ratings on visual analogue scales and were presented with an ad libitum lunch meal of preselected sandwiches 180min after consumption of the breakfast. The results showed a significant difference in energy and macronutrient intakes at the ad libitum meal between the three oils with the MCT oil reducing food intake compared to the coconut and control oil. Differences in food intake throughout the day were found for energy and fat, with the control having increased food intake compared to the MCT and coconut. The MCT also increased fullness over the three hours after breakfast compared to the control and coconut oils. The coconut oil was also reported as being less palatable than the MCT oil. The results of this study confirm the differences that exist between MCT and coconut oil such that coconut oil cannot be promoted as having similar effects to MCT oil on food intake and satiety.