Optical identification andor authentication of a document or item with the help of a marking comprising a random distribution of circular polarized light reflecting particles, the marking being applied to the document or item through an ink, and the reading device exploiting circular polarization to discriminate the flakes from the background. The device provides a lower DBR structure, an active layer, a current injection layer, a current blocking layer, and an upper DBR structure on a GaAs substrate. Consumption of the compositions after eating a desired amount of food may habituate the individual to ending a meal and serve to cue cessation of eating, assisting the individual with ending a meal at a time point before a signal of satiety has reached the brain. Information about the respective components, as well as process parameters, can be stored on the unique identifier for later reference. 8% as measured according to the Elongation Test Method are provided.