Chyavanprash, the torchbearer of ayurveda medicine and known for centuries as one cure for all ills, may not be so efficient as its manufacturers claim. Studies by the L M College of Pharmacy reveal that amla, the major ingredient which goes into chyavanprash preparations, loses all the Vitamin C , or its potency by the time the concoction cools down and is packed off to the retailer waiting for a Rs 100 crore market in India.