Emergence of spices as valuable health protectants has put them on a high pedestal and there are many scientific groups working on some of the promising spices, especially Turmeric, Chilli, Black Pepper and Ginger. The active constituents in them like Curcumin, Capsaicin, Piperine etc are now available in the market in tablet or capsule forms for easy consumption for those not liking their flavor or taste. Latest to be focused by health experts is Chilli and its Capsaicinoids which have been found to be an aid to burn excess calories in the body in those wanting to shed their extra body weights. However it is not the well known "hot"Capsaicin that is responsible but one of its lesser known derivatives present in Chilli, Dihydrocapsiate which brings about the beneficial effect.
Chilli is invariably associated with the hot sensation it gives when consumed and hitherto its value is estimated based on the Capsaicin content, the active principle responsible for the sensory effect. While bell pepper or the commonly known Capsicum has practically no value as a source of pungency as measured by the Scoville Heat Units (SHU), the hottest chilli is reported to be grown in Nagaland in India, the two varieties Naga Morich and Naga Jolakia with SHU values approaching the one million mark. Pure Capsaicin extracted from this spice has an SHU value of 16 million! With the advent of oleoresin technology Capsaicin recovery has become more efficient and the super critical fluid CO2 extraction yields high purity Capsaicin. Because of its hot sensory perception not tolerated by many, Capsaicin has found greater acceptance for external application like ointments and dermal patches for pain relief in humans. A concentration of 0.025% to 0.075% is considered adequate in such preparations to get the desired effect. Pain relief for patients suffering from peripheral neuropathy and acute neuralgia is now being managed successfully with Capsaicin containing dermal patches.
Chilli contains other Capsaicin related chemical substances like Dihydrocapsaicin, Norhydrocapsaicin, Homodihydrocapsaicin, Homocapsaicin and Nonivamide but unlike Capsaicin, these compounds do not have the "heat" property. This is an advantage that can be exploited for formulating products with the health protecting abilities of Capsaicin without causing the discomfort of the burning sensation. Interestingly the concentration of Dihydrocapsaicin can be as high as 2.39 mg/gm of chilli compared to 3.76 mg/gm of Capsaicin. Recent findings that Dihydrocapsaicin can be an antiobesic supplement gains significance and may eventually a popular route for weight shedding without "pain". The key to the finding is that both Capsaicin and Dihydrocapsaicin work the same way in achieving weight reduction through the TRPV-1 route.
The natural question is, if the body does not absorb the Dihydrocapsaicin, how does it boost metabolic activities that results in more burning of calories preferentially from the fat. It is believed that the Capsaicinoids temporarily bind with the receptor protein (Transient Receptor Potential Vanilloid-1) present in the intestine. This acts as a trigger sending a signal to the brain, which in turn sets in motion a chain of events that effectively boosts the metabolic rate in the body. Probably same process occurs when people eat hot Chilli preparations resulting in sweating. Why Dihydrocapsaicin is preferred to Capsaicin can be explained away by the "heatless" characteristics of the former when consumed in adequate quantities required to trigger the magnitude of effect to be achieved without causing intense fiery distress to the human mouth and gut.What is interesting is that this compound does not cause any burning sensation or the "heat" that is associated with Chilli because due to its molecular structure it does not fit into the normal oral receptors and thus avoids the irritation in the mouth or the gut. Added to this it is not absorbed in the GI and therefore will not be a load for the liver to metabolize. A small quantity of 3-9 mg intake per day is reported to be adequate to shed significant body weight over a small period of time according to the study carried out with a small number of obese subjects. According to the latest scientific findings a high dose of Dihydrocapsaicin when taken as supplements can burn as much as 160 calories. Though the news can be music to the ears of many weight watchers with a desire to lose weight, further studies are needed over longer periods of time to really quantify the benefit and standardize effective preparations, including optimum dosage that will achieve maximum result. Also necessary caution is advised against taking these findings as a "silver bullet" for weight control because at best, if the findings are confirmed, this can at best play a secondary role to boost the value of exercise and diet control in any regime to control weight.