Hands are the principal tool of human exchanges, and each individual’s hands encounter different environments and handle different materials. Moreover, they are the key and richest source of sensorial tactile perceptions, i.e., rough, even, cold, warm, soft, hard, etc. Hands also frequently provide symbols and perceptions of human personality, energy and mood, and because these multitasking tools are easily soiled, they must be frequently cleansed.
Hands use human muscle energy to apply mechanical action to surfaces, bodies, instruments and machinery. They have a complex structure. The palm and the fingertip contain one of the densest networks of nerve endings of the body. Skin morphology is unique in the palm area: It is glabrous, relatively thick and lighter than the skin of other body parts. It is covered with papillary ridges, acting as friction pads. The hairy skin of the dorsal site is thin, soft and pliable. The border tissue around the fingernail structure, called the paronychium, is thin and easily inflamed. It can host a high bacterial charge that may induce painful reactions. The structure of the hands is complicated by aging, which further aggravates dryness, skin thinning, fissures and anelastic behavior.
No ideal hand care product profile seems to exist but there are some common elements that can guide formulation strategies for this specific site. First of all is the need to soothe and control the intense and sometimes painful skin dryness following the frequent use of cleansing products, which is especially true for the aging population. In other cases, there is a need for equalizing uneven blood flow in the extremities that occurs with changing temperature and leads to intensive and variable reddening. Dark spots on the back of the hands are also a frequent problem, mostly resulting from skin aging and sun overexposure. Further, increasing consumer awareness about the daily risks of bacterial and mycotic contamination when touching soiled surfaces, human bodies and common objects has given rise to a large variety of hand sanitizers, all claiming long-lasting hygiene and bacterial protection. These worries concern both men and women, leading to formulations that should sensorially appeal to everyone.