Saludable vs. sano
The Spanish words 'saludable' and 'sano' both translate to 'healthy' in English. The usage of these two words, however, differ slightly in context.
Saludable
'Saludable' refers to something that promotes health or is beneficial to maintaining good health.
Es importante tener una dieta saludable para mantener un buen estado físico.
(It's important to have a healthy diet to maintain good physical shape.)
Hacer ejercicio regularmente es muy saludable.
(Exercising regularly is very healthy.)
Un ambiente saludable es vital para el crecimiento de los niños.
(A healthy environment is vital for children's growth.)
Sano
'Sano' primarily refers to a state of being free from illness or disease, it can also be used roughly equivalently to 'saludable'.
Mi abuela es muy vieja pero todavía está sana.
(My grandmother is very old but she is still healthy.)
El médico dijo que estoy sano después de la revisión.
(The doctor said I am healthy after the check-up.)
Una relación sana es la base para un matrimonio feliz.
(A healthy relationship is the foundation of a happy marriage.)
Summary
'Saludable' and 'sano' both refer to a state of wellness, but 'saludable' typically emphasizes habits or lifestyles that promote good health, while 'sano' denotes an absence of illness or poor health and may suggest a state resulting from good health practices.