The Bhagavad Gita's seventeenth chapter extends the three gunas into a working classification of food, giving, speech and action, and rajasic food is described there as bitter, sour, salty or excessively hot, the kind that brings pain, grief and disease when taken to excess, favoured by those it says are driven by desire for results rather than by clarity. The same grid marks a gift given for gain, or expecting something in return, as rajasic rather than sattvic, extending the guna beyond metaphysics into everyday ethical judgement.
No substance or person is held to be purely rajasic; all three gunas are always present together, and rajas is generally treated as the quality that must be reduced, not eliminated outright, since some measure of activity and drive is needed to accomplish anything at all, including the disciplined practice aimed at increasing sattva in its place. Spiritual effort is itself, in this analysis, a rajasic act undertaken in service of a sattvic goal.
Popular treatments sometimes flatten rajas into a simple label for stress or ambition, dropping the doctrine that all three gunas coexist in every person and substance and that the aim is a shifting balance rather than the elimination of one guna in favour of a fixed, permanent other.