Immunity in Ayurveda can be understood under multiple topics. Among them the most important is Bala or the concept of strength, Vyadhi Kshamatva or the concept of supreme resilience. The concept of Bala explains the ability of the system to repair and nourish itself and be effective in diseases prevention whereas Vyadhi kshamatva is the ability of the immune system to fight against the diseases causing pathogens.

Ayurveda focuses on following plans for acquiring Bala or enhancing immunity:

Proper and suitable Ahara, performing exercise with proper method, using different beneficial Rasayana yogas.
 

Balavardhaka bhava (factors which increases strength\immunity) as described by Acharya Charak are-

• Birth in a place where people are naturally healthy or strong, birth in family of strong person (means without any family history of immune deficient disorders),
• Birth at the time when people naturally gain strength (Visarga Kala), favorable time, excellence among qualities of Bija (sperm and ovum)
• Kshetra (uterus)
• Excellence of . . . . . . diet (Ahara Sampat)
• Excellence of physique (Shareera Sampat)
• Excellence of suitability (Satmya Sampat)
• All mental faculties are proper (Sattva Sampat)
• Natural mechanism (Sabhavsiddha)
• Young age
• Exercises

In Ayurveda Oja is considered as vital in the defense mechanism of the body. It resides in the heart but also circulates all over the body and maintains health status of the person.

If this is lost, life is also lost, where as if this is intact, life also continues and sustained.:

According to the concept of Ojas or Bala or Vyadhikshamatva, the body’s resistance is of tremendous importance in the daily welfare of living beings not only for diseases prevention but also for rapid recovery after diseases affliction.
 

After all the ability to withstand change can only be developed by maintaining a state of equilibrium in the body, mind and soul. So, one should always work for enhancing the immunity.