How do sunless-tanning products work?
If you’ve read our article How Sun Tans and Sunburns Work, you know that skin is made up of two main layers: the epidermis on the outside and the dermis on the inside. Whether you are talking about sun tanning or self-tanning, the epidermis is where the action occurs. The epidermis is also made up of layers. The deepest layer of the epidermis, called the stratum basale (basal layer), is affected during sun tanning. The stratum corneum (horny layer) is the outermost layer of the epidermis — it is this layer that is affected by most sunless-tanning products. There are several different kinds of sunless-tanning products available today. People have been able to pour on a tan since 1960, when Coppertone came out with the first sunless-tanning product — QT or Quick Tanning Lotion. If you are old enough to remember this, then you are probably thinking of the incredibly orange hue this lotion produced. Since then, there have been several advancements made on the
