Background and purpose: Capsaicin, the active ingredient of chilli, and medium-chain triglycerides (MCT) have been shown to increase diet-induced thermogenesis (DIT), improve satiety and decrease energy intake. Combinations of thermogenic ingredients have previously been investigated such as mustard and chilli, or capsaicin and green tea with positive effects. The aim of this study was to investigate the combined effects of chilli and MCT feeding on DIT and satiety in healthy volunteers.
Methods: Seven healthy volunteers were tested on four occasions following an overnight fast. Volunteers were fed a breakfast containing chilli and MCT oil, chilli and sunflower oil, bell pepper and sunflower oil or bell pepper and MCT oil. Satiety and gastrointestinal comfort were measured using visual analogue scales (VAS) and category scales. Baseline energy expenditure, and DIT and fat oxidation were measured for 6 h using indirect calorimetry.
Results: There were significant differences in DIT between the meals (P = 0.003) which increased from 7.0 % for pepper-sunflower oil to 10.7 % for chilli-MCT oil. The predominant differences existed between the chilli-MCT oil and chilli-sunflower oil (P = 0.013), between chilli-MCT oil and pepper-sunflower oil (P = 0.007) and between pepper-sunflower oil and pepper-MCT oil (P = 0.004). There was a significant difference in fat oxidation between the pepper-sunflower oil and pepper-MCT oil (P = 0.032). There were no differences in any VAS satiety parameters or gastrointestinal comfort ratings.
Conclusion: Adding chilli and MCT to meals increases DIT by over 50 % which over time may cumulate to help induce weight loss and prevent weight gain or regain.