As for ancient Greek medicine, in order to stay healthy we should keep an eye on:
Light and Air (aer)
Food and Drink (cibus et potus)
Exercise and Rest (motus et quies)
Sleep and Wakefulness (somnus et vigilia)
Retention and Evacuation of wastes (secreta et excreta)
Perturbations of the mind and Emotions (affectus animi)

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What are the 6 non-natural things to keep in balance ?