Underwear that smells like vanilla, T-shirts with vitamin C and stockings with aloe vera are all examples of bio-functional garments developed since the textile industry followed the example set by the food industry.

The garments have some additional use beyond usual functions of covering the body and keeping it warm. They either smell nice, as in the case of the vanilla underwear, provide the user with some kind of personal care product, as in the vitamin C T- shirts and aloe vera stockings, or they might absorb a bad smell. Whet-her the clothes keep their promises is a contentious matter. Experts fear the garments could lead to allergic reactions.

One method involves simply putting the substance on the surface of the material, said Hans-Juergen Buschmann, a chemist at the German textile research centre in Krefeld. Aloe vera, a plant-based product found in many lotions or jojoba, used in cosmetics as a moisturiser, is applied to textiles in this way. The catch is the substances eventually are washed out of the clothes.