Researchers from Denmark and the Netherlands report sweet pepper may also reduce energy intake during positive energy balance, according to findings of their 27-person study published in Clinical Nutrition.
“We conclude that thermogenic food ingredients have energy intake reducing effects when used in combinations, and in positive energy balance,” wrote the researchers, led by Professor Margriet Westerterp-Plantenga from Maastricht University.
“These results suggest that bioactive ingredients (capsaicin, green tea, CH-19) may be helpful in reducing energy intake to prevent body weight gain and may support body weight loss by relatively sustaining satiety and suppressing hunger,” they added.
The research taps into the burgeoning weight loss and management market, estimated to already be worth $7bn (€5.2bn) globally. It also has implications for diabetes.
With 50 per cent of Europeans and 62 per cent of Americans classed as overweight, the food industry is waking up to the potential of products for weight loss and management.
The slimming ingredients market can be divided into five groups based on the mechanisms of action - boosting fat burning/ thermogenesis, inhibiting protein breakdown, suppressing appetite/ boosting satiety (feeling of fullness), blocking fat absorption, and regulating mood (linked to food consumption).
Westerterp-Plantenga and her co-workers recruited 27 people with an average age of 27 and an average BMI of 22.2 kg/m2, and randomised them to three weeks of negative (less calories consumed than used) and three weeks of positive energy balance (more calories consumed than used). During these periods ten separate test days were used to test the effects of capsaicin, green tea, CH-19 sweet pepper, capsaicin plus green tea, or placebo on appetite, energy intake, body weight and heart rate.
Only the CH-19 and the capsaicin plus green tea combinations produced a reduction in energy intake during the positive energy balance period. Moreover, the combined supplement produced suppressed hunger and increased satiety, and this was greater during negative than positive energy balance, wrote the researchers. This indicated that energy balance did not affect energy intake but did affect appetite.
Commenting on the mechanism, the researchers note that both catechins and caffeine in green tea may be behind the effects, with epigallocatechin gallate (EGCG) previously noted to reduced food intake and body weight in rats.
On the use of capsaicin the researchers note that long-term intervention is “hardly possible and results in bad compliance”, and that CH-19 sweet pepper, which is non-pungent, could be “an attractive alternative to capsaicin”.
“Since CH-19 sweet pepper was an efficient suppressor of energy intake it would be of interest to investigate if a combination of CH-19 sweet pepper and green tea leads to a similar synergistic effect on energy intake,” wrote Westerterp-Plantenga and her co-workers.
“Capsaicin only increases liking of the food when used at lower concentrations, and one can only comply with a relatively small dosage of capsaicin over the longer term.
“Therefore we suggest that a lower dosage of capsaicin should be combined with other bioactive ingredients (e.g. CH-19 sweet pepper) in order to reach optimal effects,” they concluded.
Source: Clinical Nutrition Published online ahead of print, doi: 10.1016/j.clnu.2009.01.010“Effects of capsaicin, green tea and CH-19 sweet pepper on appetite and energy intake in humans in negative and positive energy balance” Authors: H.C. Reinbach, A. Smeets, T. Martinussen, P. Møller, M.S. Westerterp-Plantenga Abstract available here.