Mind is manufactured out of the food that we take. Subtlest part of food reaches upward to the heart and thence entering the arteries, and thereby bringing into existence the aggregate of the organs of speech and being changed into the form of the mind, it increases the mind.
As per Chhandogya Upanishad, the food that we take is transformed in three different ways: the gross or the heaviest part of it becomes the excrement; that of medium density is transformed into flesh and the finest part goes to form the mind. Just as in the churning of curd, its fine particles rise up and are transformed into butter, so when food is consumed, the subtlest part rises up and is transformed into mind.
QUALITY OF MIND DEPENDS UPON QUALITY OF FOOD
Food has a direct and intimate connection with the mind and plays a vital part in the make-up of the mind. Sattvic diet calms the mind. Rajasic diet excites the mind. Note the difference in nature between a tiger which lives on flesh and a cow which lives on grass. Food exercises important influence on the mind. You see it clearly every day. It is very difficult to control the mind after a heavy, sumptuous, indigestible, meal. The mind runs, wanders and jumps like a monkey all the time. Alcohol causes tremendous excitement in the mind.
Food plays an important role in meditation. For purposes of meditation, the food must be light, Sattvic and nutritious. The body is made up of food. When the quality of the mind depends upon the quality of the food taken, it is natural to insist in the interest of the highest morality upon a kind of Sattvic regimen of diet for those aspirants who lead a contemplative life and householders who are attempting to lead a spiritual life in the world.
WHEN FOOD CAN BE DISPENSED
Food is only a mass of energy. Water supplies energy to the body. Air also furnishes energy. You can live without food for very many days, but you cannot live without air even for some minutes. Oxygen is even more important. What is wanted to support the body is energy. If you can supply the energy from any other source, you can dispense with food entirely. Yogis keep up the body without food by drinking nectar. This nectar flows through a hole in the palate. It dribbles and nourishes the body. A Jnani (Self Realized Person) can draw energy directly from his pure, irresistible will and support the body without food. If you know the process of drawing the energy from the cosmic energy or solar energy, you can maintain the body with this energy alone for any length of time and can dispense with food.
Evolution is better than revolution. Do not make sudden changes in anything, particularly in
food. Let the change be gradual. The system should accommodate it without any hitch. Natura non facil saltum (nature never moves by leaps). Take any food that suits you. Do not make much fuss about it. Any food that is readily available and that agrees with your system is harmless.
Mind – Its Mysteries and Control by Sri Swami Sivananda