PURINA PRO PLAN Light Adult – Rich in Turkey contains OptiRenal, a special mixture of nutrients including vitamins C and E, beta-carotene, arginine and the omega-3 fatty acid EPA. OptiRenal has been proven to improve kidney function and slow the ageing process of the kidney, to support lifelong healthy kidney function. This exclusive recipe was developed to protect the kidneys of adult cats, one of the biggest health concerns of cat owners.