Upanishads: Mind rests on the Breath!

Stress or anxiety stems from the uncontrolled stream of thoughts in the mind. The quickest and easiest way to clear the mind and cope with stress is to become aware of ones breathing. The "mind and breath connection" was so clearly understood by those wise sages of ancient India who expounded this connection in the ancient masterpiece, the Upanishads written around 500 BC.

‘As a bird when tied by a string flies first in every direction, and
finding  no  rest  anywhere,  settles  down  at  last  on  the  very  place
where it is fastened, exactly in the same manner, my son, that mind after flying in
every  direction,  and  finding  no  rest  anywhere,  settles  down  on
breath; for indeed, my son, mind is fastened to breath. 

Upanishad: "Quality of food = Quality of mind"

For eons, the highly learned Brahmin communities in India have attached immense importance to the quality of food one consumes. Sattvik (ie freshly cooked, warm, wholesome, tasty, mildly spiced) food is recommended at all times. Stale or even slightly old food is abhorred.

Even in this age of fast food, refrigerated, packaged and processed food, some folks like my mother-in-law are insistent on cooking every meal fresh despite the inconveniences. The reason for this fixation goes back to the ancient religious texts ie the Upanishads written way back in 500BC

"The food when eaten becomes threefold; its grossest portion becomes feces, its middle portion flesh, its subtlest portion mind" - The Upanishads (translated by F. Max Muller)

The Upanishads reveal the extent to which the mind is influenced by the food that is consumed. A person's mental constitution and thinking is fed by food. In the purity of food there is purity of mind;  Clarity of thought and a firmly grounded, pure intellect can only arise from a pure mind. Hence the great emphasis on pure or Sattvik food.