A Spiritual Fast

Bahá'ís practice fasting as a discipline for the soul; they see abstaining from food as an outer symbol of a spiritual fast.

By this they mean the practice of self-restraint in order to distance oneself from all the appetites of the body and so concentrate on oneself as a spiritual being and get closer to God.

Abstaining from food is not an end in itself but a symbol, and if it doesn't result in improvements in character and concern for others then it has not been undertaken in the right spirit.