When our digestive ability, or agni, is strong, we create healthy tissues, eliminate waste products efficiently, and produce a subtle essence called ojas. Ojas, which is a Sanskrit word that means strength, can be envisioned as the innermost vital essence. According to Ayurveda, ojas is the basis for clarity of perception, physical strength, and immunity. On the other hand, if our agni is weakened through improper eating, lack of activity, negative emotional energy or unhealthy daily routine, our digestion will be hampered and we produce toxins that get stored in the body. According to Ayurveda, this toxic residue, known as ama, is the root cause of disease.