Maximum tolerable dose of red pepper decreases fat intake independently of spicy sensation in the mouth

Abstract

Dietary red pepper suppresses energy intake and modifies macronutrient intake. We have investigated whether a stimulus in the mouth and the sensation of spiciness are necessary for red pepper-induced changes in energy and macronutrient intake in human volunteers. In a preliminary test, sixteen Japanese male volunteers tasted samples of a soup with graded doses of red pepper in order to define a moderate and a maximum tolerable (strong) dose of red pepper. On the day of the experiment, a standardised breakfast was given to the volunteers. At lunchtime, the subjects ingested one of four experimental soups containing either a placebo, a moderate or a strong dose of red pepper plus placebo capsules, or a placebo soup plus capsules delivering a strong dose of red pepper. The rest of the meal was given ad libitum to all subjects. The amount of food, protein and carbohydrate ingested was similar for all conditions. Energy and fat intake were similar after the ingestion of the moderate soup compared with placebo. However, the strong soup significantly lowered fat intake compared with placebo (P¼0·043), and ingestion of strong capsules also tended to suppress it (P¼ 0·080). Moreover, energy intake after strong soup and capsules tended to be lower than placebo (P¼0·089 and 0·076, respectively). The present results indicate that the maximum tolerable dose is necessary to have a suppressive effect of red pepper on fat intake. The main site of the action of red pepper is not in the mouth. Red pepper: Spiciness: Macronutrient intakeObesity is an important cause of morbidity and is having an increasingly negative impact on healthcare systems in both industrialised and developing countries (Taubes, 1998;Wickelgren, 1998). Obesity can be simply described as the outcome of a positive energy balance characterised by an excess of energy intake over expenditure. Consequently, the prevention and treatment of obesity is possible through an increase in energy expenditure or a decrease in energy intake. Capsaicin, the pungent principal of red pepper, is known to enhance energy metabolism via a stimulation of the sympathoadrenal system (Watanabe et al. 1991). As a result, an ingestion of capsaicin decreases body-fat mass in a dose-dependent manner (Watanabe et al. 1991). The ingestion of red pepper stimulates the postprandial increase in RMR and the thermic effect of feeding (TEF), suppresses energy intake and modifies macronutrient intake (Yoshioka et al. 1999(Yoshioka et al. , 2001). Dietary fat is an important factor in the development of obesity because of its high energy density (Warwick & Schiffman, 1992), its low potency to induce satiety (Lissner et al. 1987;Kendall et al. 1991;Thomas et al. 1992) and its little contribution to the TEF (Flatt et al. 1985;Schutz et al. 1989;Bennett et al. 1992). These studies led to the proposal that capsaicin (red pepper) could be useful to treat obesity or prevent its development (Doucet & Tremblay, 1997;Dulloo, 1998). Diamond et al. (1985) have demonstrated that the TEF consists of a cephalic p...

Body fat loss achieved by stimulation of thermogenesis by a combination of bioactive food ingredients: a placebo-controlled, double-blind 8-week intervention in obese subjects

“…Two studies have shown that the stimulating effect of CAP may occur both in the mouth and in the gastrointestinal regions by stimulating sensory pathways activating SNS in a dose-dependent manner. 11,12 However, in the present study we found no differences between the simple and controlled release versions of the compound on stimulation of thermogenesis, which contradicts our previous findings about the lack of thermogenic effect of the enterocoated version. 33 Even though there was a significant and maintained thermogenic effect of the compound after 8 weeks of supplementation, we failed to find a significant association between body fat loss and change in RMR.…”

“…It has been shown that CAP added to meals increases EE and fat oxidation 8,9 and decreases appetite 9,10 in humans, probably by stimulating sensory pathways in the mouth and in the gastrointestinal regions, leading to activation of SNS in a dose-dependent manner. 11,12 The effect of caffeine on appetite and thermogenesis is rather weak, and a supplement with caffeine 200 mg t.i.d. did not produce weight loss in obese subjects.…”

Bioactive food stimulants of sympathetic activity: effect on 24-h energy expenditure and fat oxidation

“…One could speculate that the reduction in energy intake could partly be attributed to a reduced palatability of the diet when red pepper was added. However, two studies have found that the EI reducing effect of capsaicin may occur both in the mouth and in the gastrointestinal regions by stimulating sensory pathways activating SNS in a dosedependent manner (Westerterp-Plantega et al, 2004;Yoshioka et al, 2004). Therefore, the trend towards a reduced energy intake seen in the present study may lead to weight loss with higher doses taken over a longer period.…”

The effect of 4-week chilli supplementation on metabolic and arterial function in humans

“…Human data suggest that adding chilli to a meal lowers total energy and macronutrient intake (Yoshioka et al, 1999;Yoshioka et al, 2001;Yoshioka et al, 2004;Belza and Jessen, 2005). Chilli also increases postprandial energy expenditure (EE) (Henry and Emery 1986;Yoshioka et al, 1995;Yoshioka et al, 1998), fat oxidation in women (Yoshioka et al, 1998) and carbohydrate oxidation in men (Yoshioka et al, 1995;Lim et al, 1997).…”