Appetite and the capacity to digest.
An assessment of the capacity of a patient to ingest,digest, and assimilate food. The duration between consuming a meal and the next one is a measure of agnibala, or the strength pf the digestive fire. An optimal ahara shakti, indicate a quicker expected recovery from disease and imbalance. The capacity of consumption of food and its digestion is thus taken as an indicator of health or morbidity.
Text Source: https://books.google.com/books?id=YZNtAwAAQBAJ&pg=PT27&lpg=PT27&dq=Ahara+Shakti&source=bl&ots=k3yjwBcnBe&sig=FY61douz2EGBrtLqMH8-lRrhHQw&hl=en&sa=X&ved=0CCwQ6AEwAWoVChMI-53d-_i_xwIVR82ACh1HvwM7#v=onepage&q=Ahara%20Shakti&f=false