Harmful substances are secreted from an organism in several ways. One of them is the sudoriferous glands present in the skin dermis. They prevent overheating of the organism (they help regulate body temperature), remove water by the process of perspiration and also the products of metabolism in this water. The highest concentration of the sudoriferous glands is in the armpits, under the knees, on the soles and on hands. Excessive perspiration can be reduced by using antiperspirants, and the conceivable bad smell can be reduced with the aid of deodorants.