I think we should not forget, what has been demonstrated scientifically for more than half a century. That organisms under properly reduced but nutritious intake, experience an increase in resistance to virtually all diseases, and maintain muscle mass throughout advance age, the quality of the muscle also remains akin to that of a young organisms... Their mental abilities appear prolonged indefinitely, and their tissues tend to be more resistance to a myriad of toxins, and capable of withstanding periods with lack of oxygen with far less damage.