The Gita lays considerable emphasis on the three Gunas or qualities of Nature and their action. Understanding of the Gunas is certainly helpful both to reduce the sense of the ego, which believes it has totally free will and controls how it responds to life circumstances, and to aid the individual in effectively acting in the world. Having previously provided a general description of the nature of each of the three Gunas, the Gita then begins to enlarge upon this by providing detailed analysis of the action of the Gunas in a variety of forms and circumstances. Since the Gunas are involved in the entire manifested creation, we find their influence in all material forms, life energies and mental characteristics.
Sri Aurobindo describes the Gunas as follows as they impact the food we eat: “Our food, for example, the Gita tells us, is either sattwic, rajasic or tamasic according to its character and effect on the body. The sattwic temperament in the mental and physical body turns naturally to the things that increase the life, increase the inner and outer strength, nourish at once the mental, vital and physical force and increase the pleasure and satisfaction and happy condition of mind and life and body, all that is succulent and soft and firm and satisfying. The rajasic temperament prefers naturally food that is violently sour, pungent, hot, acrid, rough and strong and burning, the aliments that increase ill-health and the distempers of the mind and body. The tamasic temperament takes a perverse pleasure in cold, impure, stale, rotten or tasteless food or even accepts like the animals the remnants half-eaten by others.”
Sri Aurobindo, Essays on the Gita, Second Series, Part II, Chapter 18, The Gunas, Faith and Works, pp. 468-469