Chewing increases postprandial diet-induced thermogenesis

Slow eating, which involves chewing food slowly and thoroughly, is an effective strategy for controlling appetite in order to avoid being overweight or obese. Slow eating also has the effect of increasing postprandial energy expenditure (diet-induced thermogenesis). It is still unclear whether this is due to oral stimuli; that is, the duration of tasting food in the mouth and the duration of chewing. To investigate the effects of oral stimuli on diet-induced thermogenesis in 11 healthy normal weight males, we conducted a randomized crossover study comprising three trials: (1) drinking liquid food normally, (2) drinking liquid food after tasting, and (3) adding chewing while tasting. Oral stimuli (i.e., the duration of tasting liquid food in the mouth and the duration of chewing) significantly increased diet-induced thermogenesis after drinking liquid food. This result demonstrates that the increase in diet-induced thermogenesis is due to oral stimuli rather than the influence of the food bolus. Increased diet-induced thermogenesis induced by chewing and taste stimuli may help to prevent overweight and obesity.

Dietary Fat Chain Length, Saturation, and PUFA Source Acutely Affect Diet-Induced Thermogenesis but Not Satiety in Adults in a Randomized, Crossover Trial

Structural differences in dietary fatty acids modify their rate of oxidation and effect on satiety, endpoints that may influence the development of obesity. This study tests the hypothesis that meals containing fat sources with elevated unsaturated fats will result in greater postprandial energy expenditure, fat oxidation, and satiety than meals containing fats with greater saturation. In a randomized, 5-way crossover design, healthy men and women (n = 23; age: 25.7 ± 6.6 years; BMI: 27.7 ± 3.8 kg/m2) consumed liquid meals containing 30 g of fat from heavy cream (HC), olive oil (OO), sunflower oil (SFO), flaxseed oil (FSO), and fish oil (FO). Energy expenditure and diet-induced thermogenesis (DIT) were determined by metabolic rate over a 240 min postprandial period. Serum concentrations of ghrelin, glucose, insulin, and triacylglycerol (TAG) were assessed. DIT induced by SFO was 5% lower than HC and FO (p = 0.04). Energy expenditure and substrate oxidation did not differ between fat sources. Postprandial TAG concentrations were significantly affected by fat source (p = 0.0001). Varying fat sources by the degree of saturation and PUFA type modified DIT but not satiety responses in normal to obese adult men and women.

Effect of the fatty acid composition of meals on postprandial energy expenditure: a systematic review

SUMMARY The energy imbalance produced by an increase in caloric intake and/or decrease in energy expenditure induces obesity. However, the fatty acid composition of a diet can affect the metabolism in different ways, having a role in the development of obesity. AIM To determine the effect of different fatty acids types and composition on Diet-Induced Thermogenesis (DIT) and postprandial energy expenditure in humans. METHODS A search in the PubMed and Web of Science databases, yielded a total of 269 potential articles as a first result; 254 were excluded according to the criteria. RESULTS Fifteen articles were used for this systematic review. The studies analyzed report different effects of the fatty acids of the treatment on the diet-induced thermogenesis. Evidence indicates that the consumption of polyunsaturated fatty acids causes a greater DIT than saturated fatty acids. Also, the consumption of medium-chain fatty acids compared to long-chain fatty acids has been shown to increase DIT. Likewise, the use of certain oils has shown positive effects on postprandial energy expenditure, as is the case of olive oil, compared to rapeseed oil. CONCLUSIONS The use of specific types of fatty acids in the everyday diet can increase postprandial energy expenditure in humans. Nevertheless, longer-term studies are required.

The Use of Plant-Based Diets for Obesity Treatment

In observational studies, individuals following vegetarian, particularly vegan, diets have healthier body weights, on average, compared with those following omnivorous diets. In clinical trials, vegetarian and vegan diets lead to significant weight loss, even in the absence of physical exercise or limits on energy intake. The mechanisms by which plant-based diets cause weight loss appear to be (1) reduced dietary energy density, as a result of their high fiber and low fat content, and (2) increased postprandial energy expenditure. The degree of weight loss associated with plant-based diets in clinical trials is as great as that with other popular diet patterns, and favorable changes in overall nutrition, plasma lipid concentrations, and blood pressure are also observed. Acceptability with, and adherence to vegan diets has been studied in varied populations in clinical trials and is similar to that of other therapeutic diets.

A Single Dose of Goji Berries Does Not Affect Postprandial Energy Expenditure and Substrate Oxidation in Healthy, Overweight Men

Background and Aim. Increasing energy expenditure is an effective strategy for the prevention of obesity. In this respect, Lycium barbarum (goji berry) is of interest, as it has been shown to increase postprandial oxygen consumption. Although this suggests that energy expenditure was also increased, energy expenditure and substrate oxidation can only be assessed accurately when both oxygen consumption and carbon dioxide production are measured. We therefore investigated the effects of a single dose of Lycium barbarum fruit on postprandial energy expenditure and substrate oxidation in a randomized, double-blind crossover trial. In addition, markers of lipid and glucose metabolism were measured. Methods. Seventeen healthy, overweight men received in a random order a meal containing 25 grams of dried Lycium barbarum fruit or a control meal matched for caloric content and macronutrient composition. Energy expenditure and the respiratory quotient were determined using indirect calorimetry before and up to 4 hours after meal intake. Blood was sampled before and after meal intake at regular intervals for analyses of plasma glucose, serum triacylglycerol, and free fatty acid concentrations. Results. Energy expenditure significantly increased after the Lycium barbarum and control meal, but no differences were found between the meals (p=0.217). Postprandial changes in respiratory quotient (p=0.719) and concentrations of glucose (p=0.663), triacylglycerol (p=0.391), and free fatty acids (p=0.287) were also not affected by Lycium barbarum intake. Conclusions. A single dose of Lycium barbarum does not affect postprandial energy expenditure, substrate oxidation, and markers for lipid and glucose metabolism in healthy, overweight men.